EXHAUST EMISSIONS  FROM UNCONTROLLED
 VEHICLES AND  RELATED EQUIPMENT USING
      INTERNAL COMBUSTION  ENGINES
                         by
                    Charles T. Hare
                    Karl J. Springer
                  FINAL REPORT
                       PART 2
                  OUTBOARD MOTORS
                Contract No. EHS 70-108
                     Prepared for
       Characterization and Control Development Branch
          Mobile Source Pollution Control Program
                        and
                 National Air Data Branch
         Office of Air Quality Planning and Standards
             Office of Air and Water Programs
             Environmental Protection Agency

                     January 1973
             SOUTHWEST  RESEARCH  INSTITUTE
             SAN ANTONIO    CORPUS CHRISTI    HOUSTON

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                                          EMISSIONS RESEARCH LABORATORY
—i
m

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                                                    AR-850
          SOUTHWEST RESEARCH INSTITUTE
          Post Office Drawer 28510, 8500 Culebra Road
                  San Antonio, Texas 78284
EXHAUST EMISSIONS  FROM  UNCONTROLLED
 VEHICLES AND RELATED EQUIPMENT  USING
       INTERNAL COMBUSTION ENGINES
                           by
                      Charles T. Hare
                      Karl J. Springer
                   FINAL REPORT
                        PART 2
                   OUTBOARD MOTORS
                 Contract No. EHS 70-108
                       Prepared for
        Characterization and Control Development Branch
           Mobile Source Pollution Control Program
                          and
                  National Air Data Branch
         Office of Air Quality Planning and Standards
              Office of Air and Water  Programs
              Environmental Protection Agency

                       January 1973
                           Approved:
                           John M. Clark, Jr.
                           Technical Vice President
                           Department of Automotive Research

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                            ABSTRACT

       This report is Part 2 of the Final Report on Exhaust Emissions
from Uncontrolled Vehicles and Related Equipment Using Internal
Combustion Engines, Contract EHS 70-108.  Exhaust emissions from
four 2-stroke outboard motors were measured before and after being
bubbled through water, and the constituents measured were:  total
hydrocarbons by FIA;  CO, CC>2, NO,  and hydrocarbons by NDIR; NO
and NOX by chemiluminescence;  ©2 by electrochemical analysis;  light
hydrocarbons by gas chromatograph;  and total aliphatic aldehydes and
formaldehyde by the MBTH and chromotropic acid methods, respectively.

       The engines tested were a Chrysler 35 hp twin,  a Mercury 65 hp
in-line four, and OMC twins  of 4 hp  and 9. 5 hp.  The engines were operated
on stationary test stands with power absorption by electric (eddy current)
dynamometers driven from the propeller shafts.   Pertinent operating data
were recorded along with emissions, and mass emissions computed  from
data gathered during this  project are used in conjunction with available
sales and usage data to estimate  national emissions impact.
                                 11

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                             FOREWORD

        The project for which this report constitutes part of the end
product was initiated jointly on June 29,  1970 by the Division of
Motor Vehicle Research and Development and the Division of Air
Quality and Emission Data, both divisions of the agency known as
NAPCA.  Currently, these offices are the Characterization and
Control Development Branch of MSPCP and the Air Quality Management
Branch of SSPCP, respectively, Office of Air Programs, Environmental
Protection Agency.  The contract number is EHS 70-108, and the project
is identified within Southwest Research Institute as 11-2869-01.

        This report (Part 2) covers the outboard motor portion of the
characterization work only,  and the other items in the characterization
work have been or will be  covered by six other parts of the final report.
In the order in which the final reports have been or will be submitted,
the seven parts of the  characterization work include; Locomotives and
Marine Counterparts;  Outboard Motors; Motorcycles;  Small Utility
Engines;  Farm, Construction, and Industrial Engines;  Snowmobiles;
and Gas Turbine "Peaking" Powerplants.  Other efforts which have been
conducted as separate phases of Contract EHS 70-108, including:  measur-
ment of gaseous emissions from a number of aircraft turbine engines;
measurement of crankcase drainage from a number  of outboard motors;
and investigation of emissions control technology for locomotive diesel
engines;  either have been or will be reported separately.

        Cognizant technical personnel for the Environmental Protection
Agency are currently Messrs. William Rogers Oliver and David S. Kircher,
and past Project Officers include  Messrs. J. L. Raney,  A. J.  Hoffman,
B. D. McNutt, and G. J.  Kennedy.  Project Manager for Southwest Re-
search Institute has been Mr.  Karl J. Springer, and Mr. Charles  T. Hare
has carried the technical  responsibility.

        The offices of the Environmental Protection Agency which have
sponsored this project are located at 2565 Plymouth Road,  Ann Arbor,
Michigan 49105 (MSPCP),  and Research Triangle Park,  North  Carolina
27711 (SSPCP).  The contractor (SwRI) is located at 8500 Culebra  Road,
San Antonio, Texas  78284.

        The  successful conduct of  the outboard motor portion of the project
owes  a great deal to assistance rendered by the Boating Industry Associ-
ation,  Outboard Marine Corporation, Chrysler Outboard Corporation, and
Mercury Marine.  The advice and cooperation of Mike Boerma of OMC,
Jerry Pok of Chrysler, Ted Morgan and Joe Swift of Mercury,  and Don Reed
of BIA have been especially valued and appreciated.  David Cole of the
University of Michigan also provided some initial testing guidelines.
                                 111

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       The personnel involved in preparation for and conduct of the
outboard tests included Russel T.  Mack,  lead technician,  and Jirnmie
Chessher,  Gene Hoyt, Ernest Krueger, Joyce McBryde, Nathan Reeh,
and Joyce Winfield.  All these people made valuable  contributions,
especially  Rusty Mack, whose ingenuity and familiarity with the equip-
ment helped make a really complicated sampling system workable.
                                  IV

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                       TABLE OF CONTENTS
                                                                   Page
 ABSTRACT                                                         ii

 FOREWORD                                                        iii

 LIST OF ILLUSTRATIONS                                           vi

 LIST OF TABLES                                                   ix

 I.     INTRODUCTION                                             1

 II.     OBJECTIVES                                                2

 III.    INSTRUMENTATION,  METHODS, AND CALCULATION        3
       TECHNIQUES

       A.  Instrumentation and Sampling System                      3
       B.   Test Procedures and Methods                             9
       C.   Calculations Leading to Mass Emissions Values           10

 IV.    RESULTS OF EMISSIONS TESTS                             14

       A.   Results of Tests Designed to Simulate Normal Operation   14
       B.   Results of Tests Designed to Investigate the Water        20
           Scrubbing Process
       C.  Results of Emissions Tests on the Chrysler 35 hp         30
           Outboard Motor Using a 3rd Order Power Curve

 V.     ESTIMATION OF EMISSION FACTORS AND NATIONAL       35
       IMPACT

       A.  Development of Emission Factors                        35
       B.  Estimation of National Impact                            42

 VI.    SUMMARY                                                  54

 LIST OF REFERENCES AND BIBLIOGRAPHY                       56

APPENDIXES

       A.  Emissions Data on a Johnson 4R71 Engine
       B.  Emissions Data on a Johnson 9R72 Engine
       C.  Emissions Data on a Chrysler  356HA Engine
       D.  Emissions Data on a Mercury 650 Engine
       E.  Estimated State and Regional Distribution of
           Outboard Motors,  1971

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                     LIST OF ILLUSTRATIONS

Figure                                                            Page

   1       Overall View of Outboard Motor Test Stands and
          Emissions Measurement Equipment                         4

   2       Overall View of Outboard Motors,  FIA Oven/Detector,
          and Wet Chemistry Sampling System                        4

   3       Detailed View of Analytical Instruments                     4

   4       Detailed View of FIA Oven/Detector Unit and Wet
          Chemistry System Used for OMC 4 hp and Mercury
          65 hp Engines                                              4

   5       Operator's  Control Panel for Johnson 4R71 Outboard
          Tests                                                     5

   6       Johnson 4R71 Engine Under Test, Dynamometer,  and
          Stroboscopic Tachometer                                  5

   7       Detail of Exhaust/Water  Contact System or "Bubbling
          Tank"                                                     5

   8       Front View of Mercury 650 Outboard Undergoing Emissions
          Tests                                                     5

   9       FIA Oven/Detector Unit Used for Tests on Chrysler 35 hp
          and OMC 9. 5 hp Outboard Motors                           6

 10       Aldehyde Sampling Apparatus on FIA Oven/Detector Unit     6

 11       Control Panel Used for Tests on Chrysler 35 hp (shown)
          and OMC 9. 5 hp Outboard Motors                           6

 12       OMC (Johnson)  9. 5 hp Engine Mounted on Test Stand         6

 13       Schematic of Exhaust Sampling and Water Contact
          Systems Used for Outboard Motor  Tests                     8

 14       Boat Loading Curves for  Outboard  Motors Based
          on the Formula hp  = KNX                                  11

 15       Hydrocarbon Emissions from Four Outboards as a
          Function of Crankshaft RPM With Simulated Boat  Load
          as Described in Tables 1 and 2                             16
                                vi

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                 LIST OF ILLUSTRATIONS (Cont'd)

Figure                                                             Page

  16      Carbon Monoxide Emissions from. Four Outboard Motors
          as a Function of Crankshaft RPM With Simulated Boat
          Load as Described in Tables 1 and 2                       17

  17      Carbon Dioxide Emissions from Four Outboard Motors
          as a Function of Crankshaft RPM With Simulated Boat
          Load as Described in Tables 1 and 2                       18

  18      Oxides of Nitrogen Emissions from Four Outboard Motors
          as a Function of Crankshaft RPM With Simulated Boat Load
          as Des cribed in Tables 1 and 2                            19

  19      Close-up Detail of  Tank Bottom with Propeller and
          Sintered Bubbler Installed                                 24

  20      Tube Bubbler With Lowest Water Flow Rate and
          Propeller Off                                             24

  21      Perforated Bubbler with Lowest Water Flow Rate
          and Propeller Off                                         24

  22      Sintered Bubbler with Lowest Water Flow Rate and
          Propeller Off                                             24

  23      Tube Bubbler with  Lowest Water Flow Rate and
          Propeller Off                                             25

  24      Tube Bubbler with  Lowest Water Flow Rate and
          Propeller On                                             25

  25      Perforated Bubbler with Intermediate Water Flow
          Rate and Propeller Off                                     25

  26      Perforated Bubbler with Intermediate Water Flow
          Rate and Propeller On                                     25

  27      Apparent Effect of  (H^O/Exhaust) Ratio on Loss  of
          Hydrocarbons During Water Contact                        29

  28      Apparent Effect of  (f^O/Exhaust) Ratio on Loss  of
          CO2 During Water  Contact                                 31

  29      Apparent Effect of  (t^O/Exhaust) Ratio on Losses of
          Oxygen and  CO During Water Contact                      32
                                 vii

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                 LIST OF ILLUSTRATIONS (Cont'd)

Figure                                                             Page

  30      Apparent Effect of Concentration on Losses of HC,
          CO2, and NOX During Water Contact                       33
                                Vlll

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                         LIST OF TABLES

Table                                                             Page

  1         Speed and Load Conditions Used for Outboard Tests         9

  2         Average Power Output Observed During Outboard
            Tests                                                   12

  3         Total Mass Emissions and Mass Emissions Retained
            in Water Phase (Experimentally) for Four Outboard
            Motors                                                  15

  4         Average Concentrations of Formaldehyde (HCHO)
            and Total Aliphatic Aldehydes (RCHO) in the Exhaust
            of Four Outboard Motors Before and After Water
            Scrubbing                                               21

  5         Average Concentrations of Light Hydrocarbons  in
            the  Exhausts  of Four Outboard Motors Before/After
            Water Scrubbing                                         22

  6         Conditions Used for Special Tests of the Mercury
            650 Outboard Motor                                     26

  7         Percentage Losses of Exhaust Gas Constituents
            During Water Contact in Special Tests on Mercury
            650                                                     27

  8         Total Mass Emissions and Mass Emissions Retained
            in Water Phase (Experimentally) for a Chrysler 35 hp
            Outboard Motor Operated on a 3.0 Order Power Curve     34

  9         OMC Outboard Motor  Operating Time Data                36

 10         Time-Based Weighting Factors for Test Modes            36

 11         Composite Power Output and  Load Factor  Calculations     38

 12         Composite Fuel Consumption and BSFC  Calculations       39

 13         Individual Air and Water Brake Specific and Fuel
            Specific Emission Factors for Four Outboard Motors       40

 14         Total Emission Factors for Four Outboard Motors         41

 15         Summary of Outboard Motor Population and Sales Data     43
                                 IX

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                     LIST OF TABLES (Cont'd)

Table                                                              Page

  16       Summary of Calculations Leading to Average Power
           of Outboard Motors in Use at the End of 1971              45

  17       Summary of Calculations Leading to Fractions of
           Outboard Motors in Service in Four Power Categories     46

  18       National Impact Estimates for Two-Stroke Water-
           Cooled Outboard Motor Emissions,  1971                   49

  19       Comparison of Outboard National Impact  Estimates
           With EPA Nationwide Air Pollutant Inventory Data         5 1

  20        Composite  Emission Factors for Use in  Small -
            Scale  Outboard Motor Impact Estimates  (Subject
            to Qualifications)                                        52

  21        Summary of Regional and Seasonal  Variation of
            Outboard Motor Emissions                               53

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                         I.  INTRODUCTION

       The program of research on which this report is based was
initiated by the Environmental Protection Agency to (1) characterize
emissions from a broad  range of internal combustion engines in
order to accurately set priorities for future control, as required.and
(2) assist in developing more inclusive national and regional pollution
inventories.  This  document, which is  Part 2 of a planned seven-part
final report, concerns emissions from outboard motors and the
national  impact of these emissions.

       Prior  to the subject program, very little quantitative research
on outboard motor  emissions had been  performed, and the results of
the small amount of previous work were not available. The experience
of several manufacturers in performance testing, however, was made
available and proved to be very valuable.  At the time of the tests,  only
little consideration had been given to standardized emissions test pro-
cedures  for outboards by professional groups, so no well thought-out
procedures had been written.  As a  consequence of the general lack of
knowledge on  the subject, procedures were developed which would ful-
fill project requirements as well as possible,  but little consideration
has been given to their potential usefulness for anything except research
purposes.

       All the outboard motor exhaust  emissions testing was performed
in the Emissions Research Laboratory  between January 1 and  August 10,
1972, although not  continuously. As an additional task (Task VII) under
the same contract,  however,  a separate research program is  being
performed to  evaluate crankcase drainage emissions from in-service
outboard motors.   This latter task will be considered in this report only
insofar as it affects exhaust emissions, and the impact of the drainage
itself will be treated in a separate Final Report on Task VII.

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                           II.  OBJECTIVES

       The primary objectives of the outboard motor portion of this
project were to collect exhaust emission data  on four outboard motors,
and to use these data with available population and usage information
to estimate the national emissions impact of outboards.  The emissions
to be characterized included total hydrocarbons (FIA) ; CO,  CO2,  NO,
and hydrocarbons (NDIR); NO and NOX (chemiluminescence); O£( electro-
chemical) ; light hydrocarbons (gas chromatograph); and aldehydes by
wet chemistry.  These constituents are essentially the same as those
measured  for all gasoline-fueled engines operated under this contract,
and particulate was not measured due to the complex configuration of the
outboard exhaust systems.  Emissions of Sulfur Oxides (SOX) were cal-
culated on the basis of fuel consumed,  rather than being measured.

       As part  of the overall objective of gathering emissions data,  it
was  necessary to design testing procedures which would simulate  real-
life operation as closely as possible.  For  outboards this task consisted
not only of determining realistic speeds and loads,  but also of developing
the hardware necessary to measure exhaust gas concentrations both before
and after the gases were  bubbled through water.  Anticipating the  removal
of some exhaust gas constituents by the water, it was planned originally to
make analyses of the water before and after exhaust gases were bubbled
through it  as a cross-check on the gas  analysis.  This plan did not prove
feasible because preliminary calculations based on changes in exhaust
constituents  showed that relatively small changes would be occurring in
the water phase, requiring instrumentation more sensitive than that
available in order to collect quantitative data.

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III. INSTRUMENTATION,  METHODS, AND CALCULATION TECHNIQUES

       Several aspects of this study make it something of a departure from
more routine emissions measurements; namely, the fact that the motors
tested were of 2-stroke design (2-strokes dominate the field), that they
had rather complicated exhaust systems designed for underwater discharge,
and that operation at the air/water interface meant that their exhaust
products might affect both phases. Three parts of the technical under-
taking will be discussed in this  section,  and the fourth (impact analysis)
will be discussed in section V.

A.     Instrumentation and Sampling System

       In general terms, the analysis instruments used on outboards and
treatment of the  gas  samples conformed to SAE Recommended Practice
J254.  The exceptions were (1)  use of a chemiluminescent NO-NOX
analyzer in addition to the NDIR NO analyzer,  and (2) special treatment
of some samples which consisted  of bubbling them through water before
analysis.  As an introduction to the measurement systems used  on the
subject work, Figures 1 through 8 are presented.   Figure 1  is an  overall
view showing the Johnson and Mercury outboards on dynamometer stands,
the exhaust/water contact system, and the emissions instrumentation for
CO, CO2, NDIR  NO, NDIR hydrocarbons and chemiluminescent  NOX and
NO analysis.  Figure 2 shows more detail of the engines  and water contact
system,  and the wet chemistry  sampling system and the FIA detector/oven
assembly are shown at left.   Figure 3 is  a more detailed view of the
sampling train described above, showing the FIA hydrocarbon analyzer's
remote control systems at upper right and the 4-channel  recorder at right
center.  Figure 4 shows the FIA oven and the wet chemistry system in
more detail.

       Figure 5  shows the operator's control panel for the Johnson 4R71
tests  and the two large flowmeters (bottom center) used to measure water
flow to the exhaust/water contact  system. The contact system itself,
which  can be referred to as the "bubbling tank", consisted primarily of the
plexiglass cylinder shown behind the control panel.  Figure 6 shows more
detail  of the  Johnson 4R71 engine  tested, the dynamometer and the  strobo-
scopic tachometer.   Figure 7 is a detailed view of the bubbling tank,
showing the internal  float and level control system, wall and gasket con-
struction, and typical bubbles moving through the tank.  Figure  8 shows
the Mercury 650 on the test stand undergoing emissions tests.

       Figure 9  shows the new  FIA oven/detector used for tests on the
Chrysler 35  hp and OMC 9. 5 hp engines, which also held the aldehyde
sampling apparatus,  as shown in Figure  10.  The control panel  used for
these last two engines is shown in Figure 11 along with the Chrysler
engine mounted on the test stand,  and Figure 12 documents  the test stand
installation of the OMC 9.5.

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                                                                              •i
Figure  1.  Overall View of Outboard
Motor Test Stands and Emissions
Measurement Equipment
Figure 2.  Overall View of Outboard
Motors,  FIA Oven/Detector, and
Wet Chemistry Sampling System
Figure 3.  Detailed View of Analytical
Instruments
  Figure 4.  Detailed view of FIA
  Oven/Detector Unit and Wet
  Chemistry System Used for OMC
  4 hp and Mercury 65 hp Engines

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Figure 5.  Operator's Control Panel
for Johnson 4R7 1 Outboard Tests
  Figure 6.  Johnson 4R71 Engine
  Under Test,  Dynamometer, and
  Stroboscopic Tachometer
 Figure 7.  Detail of Exhaust/Water
 Contact System or "Bubbling Tank"
Figure 8.   Front View of Mercury 650
Outboard Undergoing Emissions Tests

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Figure 9.  FIA Oven/Detector Unit
Used for Tests on Chrysler 35 hp and
OMC 9. 5 hp Outboard Motors
                                                                           r
Figure 10.  Aldehyde Sampling
Apparatus Mounted on FIA Oven/
Detector
 Figure 11.  Control Panel Used for
 Tests on Chrysler 35 hp (shown) and
 OMC 9. 5 hp Outboard Motors
Figure 12.  OMC (Johnson) 9.5 hp
Engine Mounted on Test Stand

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        The photographs just described give some idea of the physical appear-
 ance of the system, but to really understand it the schematic given in Figure
 13 is more helpful.  The complexity in evidence was not called for in the
 original design,  but various controls became necessary in the course of
 development.  Raw exhaust  entered the system and immediately went through
 a flask to remove entrained water.   Exiting this first trap,  a relief valve
 was provided to prevent contamination of the system while measurements
 were not being taken.  The flow was split three ways following the valve,
 one each for the FIA, the wet  chemistry system, and the  remaining analyses.
 The configuration just mentioned, with direct samples to  all analyzers, -was
 used to obtain raw exhaust emission concentrations.  To examine the effects
 of water scrubbing, the flow-switching valves were turned to force all the
 sample through the bubbling tank, and then the flow was again split three
 ways for analysis.  Sample  lines between the first water trap and the FIA
 and between this same trap  and the wet chemistry analysis were  heated to
 prevent condensation  of moisture, but the remaining lines were at room
 temperature (except in the water traps).

        The only major non-commercial piece of  equipment used  was the
 bubbling tank. Its wall was 12 inch O. D.  by 1/4  inch wall plexiglass tubing,
 18 inches in height, and the divider was 1/4 inch plexiglass sheet 15  inches
 in height.  The top and bottom were  made of 1/2  inch stainless steel  plate,
 faced off and finished on the inside,  and top and bottom gaskets were made
 of 1/8 inch Viton sheet.  The float was made of thin-gauge aluminum, and
 the linkage to the float valve was made of stainless steel rod and sheet.

        To allow sampling of the water which was used for exhaust scrubbing,
 valves were included in the  system just prior to the  water flowmeters and
 just downstream of the bubbling  tank.  It was later determined that no
 satisfactory results could be determined by water analysis using available
 instrumentation, so the sampling valves were not used.

        In normal operation, those parts of the system which are most vul-
 nerable to leaks, including the bubbling tank, were held under positive
 pressure.   The tank head pressure was held at 65 inches of water, gage,
 for all the engines  except the OMC 9. 5 hp because gas and water flows
 could be kept steady at that condition.  The pressure used for the OMC 9. 5
 was 50 inches of water, gage.   The gas flowrate through the contact tank
 was about 11 liters per minute, which resulted in a purging time for  the
 tank headspace of about 15 seconds.   The tank water level control was in-
 stalled to promote  better purging of the tank by running the  water level
 closer to the top of the tank without risk of getting water in the sample lines.
 The water flow rate through the tank was held at  25. 0 liters per minute for
 the Johnson 4R71 and  at 49.4 liters per minute for all the other engines
 except during "special" tests on the Mercury 650.  The special tests were
performed to determine the  effects of water/exhaust gas ratio, bubble size,
 and water turbulence on removal of soluble or condensable exhaust

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         RELIEF
                           RAVJ SAMPLE
                              TO ALDEHYDE
                                 ANALYSIS
RA» EXHAUST
RAW SAMPLE
                                BO6BUED SAMPLE
                                             QOICK.-CONNECT
                                                FOR
                                                 SAMPLES
                                        BUBBLING-
                                         TANK.
                            TO
                            NDIR. NO ^ WO,, AMD
                           CAEMILUM. NOn.
                                                  ) SINTERED  SS FILTER

                                                    FLOAT
                                                  ) FLOAT- CONTRO ULE D
                                                     VALVE.

                                                    OlO A/mln  METER

                                                 S  O-lZW'/miA METER

                                                    SVMTCHIW& VALVE

                                                    CONTROL, OR
F»frORE ta.  SCHEMATIC OF  E-K.KAUST  SAMPLIW&  AND  WATER
    CONTACT  SYSTEMS  USE.D  FOH  OUTBOARD  MOTOR  TESTS

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constituents by the water, and they will be described in more detail in
section IV.  The water/exhaust gas ratios used were dictated by available
water flow measurement instrumentation, practical sample flow rates,  and
economy considerations rather than representation of the real situation.
B.
Test Procedures and Methods
        For outboard motors, load (or power output) is a function of crank-
shaft speed, size and weight of boat being pushed,  propeller characteristics,
and other variables.  If it can be established, however, that the engine is
running at its "rated" rpm at wide-open throttle, then power output at
lower speeds can be approximated by the relationship

                          power output = K Nx

where x ranges from something over 2 to perhaps 3, depending on hull
design, matching of motor and boat,  and surface speed.  The quantity x
is about 2. 4(1) or  2. 5 for planing-hull pleasure boats,  and approaches 3
for displacement hull operation at low speed.   The constant K is evaluated
for a given boat/motor combination once x has been established by
rearranging the above equation and evaluating K at rated speed  and power:
                  K
                 Maximum rated power
                  (rated speed, rpm)x
Using this analysis for the four outboards tested during this project yielded
run conditions by mode as given in Table 1.

TABLE 1.  SPEED AND LOAD CONDITIONS USED FOR OUTBOARD TESTS
          Calculated Crankshaft Horsepower/Rpm in Modes by Engine
Mode

  1
  2
  3
  4
  5
  6
  7
OMC 4 hp
x = 3
4. 00/4500
2.81/4000
1. 19/3000
0. 35/2000
0. 09/1250
Idle(1050)

OMC 9. 5 hp
x - 2.5
9. 50/4500
7.08/4000
3.45/3000
1. 25/2000
0. 22/1000
Idle (700)
--
Chrysler 35 hp
x = 2. 5
35. 0/5000
20. 0/4000
9.8/3000
3. 5/2000
0.6/1000
Idle(llOO)
--
x = 3
35.0/5000
17.9/4000
7.6/3000
2.2/2000
0.3/1000
Idle(llOO)
--
Mercury 65 hp
x - 2.5
65. 0/5200
53.2/4800
33. 7/4000
14.9/2890
6. 0/2000
1. 1/1000
Idle(SOO)
The Chrysler 35 hp engine was run as if 5000 rpm were its rated speed
because the engine was not very stable at its actual rated speed of 4750
rpm.   The Johnson 4R71 was run at 1250 rpm instead of 1000 rpm in mode
5, and the Mercury 650 was  run at 2890 rpm instead of 3000 rpm in mode 4,

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                                                                        10
both also due to instability at the "standard"  speeds.  Another way of
arriving at intermediate-speed power output, where maximum power,
rated speed and "x" are known,  is to linearize the power equation by
taking its logarithm or to plot it on full logarithmic graph paper as has
been done for Figure 14.  The graph agrees very well with Table 1,
except for the Chrysler 35 hp  engine,  which starts out at its  actual rated
speed of 4750 rpm in Figure 14.  Power points for the Chrysler were  cal-
culated on both 2. 5 and 3rd order curves, and two (of a total of seven) runs
were made using the latter to  determine whether or not emissions would
change  significantly from those recorded using the 2. 5 order points.

        The test modes listed in Table  1 were generally run in top-to-
bottom order, but enough  runs were made in the opposite order to deter-
mine that the sequence was not significant.  After each speed/power con-
dition was established, emissions were allowed to stabilize (up to 5 minutes
required at times), and raw emissions values were recorded and noted on
on the chart readout.   Following the initial reading,  the  sample flow was
diverted through the bubbling tank, and another set of emissions numbers
was recorded and marked on the chart. If, for instance, Mode 1 was the
speed/power  condition being run, Mode 1A would designate emissions
measured after water scrubbing. 'The values for the "A" mode having been
recorded,  flow was switched back to the raw exhaust system, and another
set of values was  recorded.  In other words,  the sequence was;  1, 1A, 1,
2, 2A,  2,  . . . . ,  etc.  For the results given in this report,  modes listed
without the "A" designation are averages of raw exhaust concentrations
measured  before and after the "bubbled sample"  concentrations,  all while
the engine was being held at constant speed and load.  This procedure
helped to minimize the effect of "drifting" of emissions values during each
mode.

       Engine power output was recorded for each mode at the propeller
shaft, and these figures were generally as expected considering ambient
conditions and fractional losses in the drive trains.   The average values
are tabulated in Table 2 rather than being included in the Appendix.  Vari-
ations in engine speed were very minor from run to run, so rpm data will
not be included in the Appendix,  either.  Fuel consumption was measured
while emissions were being measured by recording time required for the
engines to consume a predetermined volume of fuel.   Fuel temperature
was recorded, and density measurements (separate for each batch of fuel)
were corrected to that  temperature before performing the volume-to-mass
conversion.  It should be noted that the gasoline used conformed to Federal
emissions  test fuel specifications^ ', similar to the standard fuel  called
Indolene 30.  Gasoline-oil mixtures conformed to manufacturer's  specifica-
tions, meaning that the correct brand of TCW-type was used in each engine
at a 50:1 gasoline:oil ratio.

C.     Calculations Leading to Mass Emissions Values

-------
                                                             11
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     £.
     oi
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-------
                                                                   12
        Emission concentration data in this report,  both in the Appendixes
 and in text, are on a "wet" basis;  that is, they have been adjusted back to

         TABLE 2.  AVERAGE POWER OUTPUT OBSERVED
                     DURING OUTBOARD TESTS
Mode
Average Observed Propshaft Horsepower/Rpm in Modes by Engine
OMC 4 hp

2.
1.
0.
0.
0.
x - 3
73/4500
74/4000
75/3000
23/2000
05/1250
Idle/(1050)
OMC 9. 5 hp
x - 2. 5
7.
5.
2.
0.
0.
29/4500
34/4000
59/3000
95/2000
17/1000
Idle/ (700)
Chrysler
x - 2. 5
28.
16.
7.
2.
0.
4/5000
1/4000
9/3000
9/2000
5/1000
Idle/(1000)
35 hp
Mercury 65 hp
x = 3
28.
14.
6.
1.
0.
4/5000
3/4000
1/3000
8/2000
2/1000
Idle/(1100)
53.
45.
29.
13.
5.
0.
x = 2.5
4/5200
6/4800
2/4000
0/2890
2/2000
9/1000
Idle/ (800)
   1
   2
   3
   4
   5
   6
   7

actual values before intake air humidity and water of combustion were
removed.  This step was not necessary only for FIA hydrocarbons and alde-
hydes,  both of which were measured "wet".  Conventional equations were
employed in  converting raw concentrations from a "dry" to "wet" basis,
but they were inadequate for "bubbled" concentration data.  For the bubbled
gases,  it was assumed that the concentration of water in the exhaust upon
leaving the water contact system was the same as that of saturated air at
the temperature of the water.  This temperature varied overall from  about
65° F to 80° F, and the corresponding assumed water content of the bubbled
gases varied accordingly.  Calculations required to extrapolate the mass
emissions to national  impact will be explained in section V.

        In order to calculate mass-based emissions from the concentrations,
use of standard carbon balance techniques for  the raw exhaust gave good
results, but a problem arose in computing mass emissions after water
contact because the amount of exhaust gained or lost during bubbling was
not known accurately.   It was decided that a  nitrogen balance would be
used, since it seemed reasonable that little or no change in nitrogen
mass flow would occur in the bubbling system.

        Nitrogen concentrations were determined for both raw and bubbled
exhaust by subtracting mole percentages of measurable  or calculable con-
stituents from 100. 0 percent.  Since the assumption made is that nitrogen
through the system is  conserved, the fraction  of the total raw exhaust
which comes out as bubbled exhaust can be calculated by the relation
 raw concentration N2
 bubbled concentration N2
/moles N2 in raw exhaust^
\ 100 moles raw exhaust /
 moles NZ in bubbled exhaust
                                   100 moles bubbled exhaust

                                 moles bubbled exhaust
                                  moles raw exhaust

-------
                                                                   13
The percent loss of each constituent, then, can be calculated by the
relation
              100
% of X lost =
raw X cone.  - /raw NZ cone
/raw N2 cone.   \   /               \
L  1.1.1  ^ TVT	    (bubbled X cone.)
\bubbled N? cone./   \	/	
                                  raw X cone.
and since these losses are for individual constituents,  they can be construed
as % losses by mass.  This (fractional) loss in the water,  multiplied by
total mass emitted,  becomes the mass rate at which each constituent is
being emitted into the water.   The remainder is the amount being emitted
into the air and can  be calculated as  100% minus the  % of X lost.  An
additional refinement in these calculations has been made by correcting
the observed losses during water contact of hydrocarbons, oxygen, and
CO to a pressure of 1 atmosphere by Henry's law.  The tank head
pressure was maintained at 65 inches of water gage (50 inches for the
OMC 9. 5 hp engine), so the corrections to observed  losses ranged from
0. 873 to 0. 910. The losses  of COz and NOX were not corrected because
Henry's  law does not apply when molecular dissociation is involved.  It
should be stressed here that the results reported do  not necessarily
reflect conditions  in the field, especially in the areas of water properties,
water/exhaust gas contact ratio, and turbulence in the mixing region.
It is probable, however,  that effects  such as those observed  do occur
to either a greater or lesser  extent.

       Note that all data which are reported in concentrations, including
that in the Appendixes and the aldehyde and light hydrocarbon data given in
the text, are reported on a wet basis, but that the "A" mode  data (after
bubbling) are not corrected to 1 atmosphere by Henry's law (concentra-
tion data only).

-------
                                                                       14
                IV.  RESULTS OF EMISSIONS TESTS

        Emissions concentration data from which the results presented
in this  section were calculated are given in detail in the Appendixes,
except  for data on aldehydes and light hydrocarbons, which are summarized
in text.  Appendix A contains data on the Johnson 4 hp engine, Appendix
B gives data on the Johnson 9. 5 hp engine, Appendix C consists of data on
the Chrysler 35 hp engine (including special tests), and Appendix D contains
data on the Mercury 65 hp engine (including  special tests).  The special
tests will be discussed in detail in subsections B and C.

A.      Results of Tests Designed to Simulate Normal Operation

        Following computations performed as described in section III. C. ,
mass emissions for the four engines have been combined and appear as
Table 3.  Note that  modes 1 through 6 are roughly comparable as to speed
and percent load among the two OMC engines and the Chrysler, but that
the extra mode (mode 2) on the Mercury means that mode 3 for the Mer-
cury is comparable to mode 2 for the  other engines (4000. rpm),  etc.  The
data given for the Chrysler are from tests using power points based on a
2. 5 order curve, and it should also be noted that the watenexhaust ratio
was 2. 25 for the OMC 4 hp engine and 4. 45 for the others.  In addition,
the propeller in the bubbling tank which was used to generate additional
turbulence during  the special tests on the Mercury 650 (reported later) was
"off"  during regular tests on the Mercury 650 and the Johnson 4R71, and
"on" during regular tests on the  other two engines.  The tube through which
exhaust gases entered the bubbling tank was called a "bubbler",  and the par-
ticular  type used for the regular tests was made of 1/2 inch stainless steel
tubing with the end welded shut,  andfourl/16 inch holes drilled in its sides.
This device was termed a "perforated" bubbler and was essentially the same
for all the regular tests,  except  that it protruded 1  inch further into the tank
for tests on the Chrysler 35 hp and Johnson 9. 5 hp engines than it did for
tests  on the other two engines^
        Table 3 contains data on raw emissions  (as they left the engines)
and the emissions which appeared to end up in the water.   To obtain the
emissions going into the air, it is necessary only to subtract the  emissions
remaining in the water from the  raw emissions.  This  step will be performed
in Section V, with certain assumptions regarding applicability of the various
combinations of water:exhaust ratio and turbulence, so that emission factors
can be developed separately for emissions into  the atmosphere and the water.

        The raw mass  emission rates in Table 3 have been plotted as functions
of crankshaft rpm in Figures 15,  16,  17,  and 18.  It is understood that
engine power output was varying exponentially with crankshaft rpm.  Figure
15 shows hydrocarbon emissions from the four  engines,  Figure  16  shows CO,
Figure  17 shows CO2, and Figure 18 depicts NOX.  It is not normal practice
to devote much analysis to CO2 emissions from land-based engines, but an

-------
                                                                               15
 TABLE 3.   TOTAL MASS EMISSIONS AND MASS EMISSIONS RETAINED
IN WATER PHASE (EXPERIMENTALLY) FOR FOUR OUTBOARD MOTORS
                 Raw Mass Emission Rate, g/hr     Loss in Water (Experimental), g/hr
      Mode

Gas
HC
CO
co2
NOX
°2
H20
HC
CO
co2
N0x
02
H2O
HC
CO
CO2
NOX
°2
H2O
HC
CO
C02
NOX
°2
H£O_
HC
CO
CO2
NOX
°2
H2O
HC
CO
CO2
NOX
02
H20
HC
CO
CO2
NOX
°2
H20
Johns.
4
577
699
2660
5.5
1560
1480
324
5.87
1980
1. 3
1010
1110
212
474
1350
0.6
565
806
168
303
748
0.2
378
507
176
275
464
0. 1
343
369
198
242
373
0. 0
358
315
	
__
--
--
--
--
Johns.
9.5
792
2140
5830
6.3
1970
4020
813
1690
5350
3.8
2040
3560
827
1520
3790
1.9
2020
2720
638
951
2180
0.7
1340
1650
413
472
885
0. 1
769
730
402
365
662
0. 1
729
564

--
--
--
--
--
Chrys.
35
2880
9310
13500
9.7
5230
12300
1850
5760
9803
6.9
33'50
8300
1550
4020
6540
3.5
2830
5650
1040
2310
4130
1.7
1880
3440
746
1080
1850
0.6
1170
1600
1030
1010
1630
0.6
1410
1480
--
--
--
-'
--
--
Merc.
65
6340
8910
32800
81.5
17700
19900
4660
6170
29200
83.4
12500
16900
2730
5030
19000
19.2
6750
11660
2120
4850
10300
3.2
5670
7760
1980
2890
6480
0.8
5000
4840
2170
2590
4300
0.8
5750
3780
1870
1610
2440
0. 5
5610
2350
Johns.
4
148
64.0
857
1.4
-86.9
1210
97.8
104
723
0. 1
60.4
931
63.4
51.7
426
0.0
-36.1
671
61.5
25.2
E94
0.0
-22.4
427
54.0
24.2
124
0.0
-17.6
306
64.0
22.0
100
0.0
-1.6
258
--
--
--
--
--
^-
Johns.
9.5
294
79.9
2330
0.5
-71.8
3190
351
83.2
2240
0.4
-106
2800
365
71. 5
1520
0.4
28.9
2120
310
68.0
867
0. 2
43.2
1280
200
45. 1
342
0.0
33. 3
558
190
31.0
261
0.0
32.5
422
--
--
--
--
--
--
Chrys.
35
1460
384
5300
2. 5
-301
9800
686
319
3910
1.9
-152
6600
572
115
2730
1.6
-177
4440
390
138
998
0.7
-45.6
2700
286
80. 5
772
0.4
63. 1
1230
378
73.6
666
0.4
48.6
1100
--
--
--
--
--
--
Merc.
65
2220
260
14300
14.4
215
16500
1350
270
13300
16. 1
-428
14300
977
177
7570
1.5
-299
9920
743
193
3830
0.9
-89. 5
6590
55Z
6.3
2450
0.3
34.6
4030
537
116
1550
0.4
67.8
3030
389
70.4
799
0.2
138
1760

-------
                                                                 16
 &OOO-
               1000
   1000
EWG-IJOE
3000
4000
                                                          5000
       15.  HYDRO C/VRfcON  EMISSIONS FROM   POOR
AS A FUNCTION OF CRA*KS>l\fcFr RPM  i\)lTH S\MUL/\TED
LOAD  AS DESCRIBED   IN  TABLES  I   AN£>  2.

-------
                                                                 17
   8000
   7000
   GOOO
   5000
2
o
   4000
J
  300O
  LOGO
   1000
      O
       0
                 IDLE
1000
ZDOO
3000
   4000


RPM
5000
         Ifc. C.AKBOK) MONOKIOE  EKIISSIONS  PROM  FOUR.  OUT&OAR..D

 MOTORS  AS   A  FOMCTtON  0*  C-?,AMK.SrtAFT R,?M IMVTK

 SIMULATED  BOAT LOAD  *s DESCR.IE.EO  IN  TABLES   \  ANJD  2.

-------
                                                        IB
     O        IOOO       2000      30OO      4000      SOOO
                   ENGINE (CRAWK^HAFT) FM>M
Fl&URE 17. CARBON DIOXIDE EMISSIONS  FROM  FOOR OOTBOARP
   MOTORS AS A  FUNCTION OF  C.R.AN)KSY\AFT  RPM WlTt^
 SIMUUATED  BOAT LOAD AS  DESCRIBED IN TA6LES I AMD 2.

-------
                                                            19
    80
>
 \

2 50
a
S.

O

Z


J
   40
   20
   IO
    OL
                                            OMC 4-Klp
                                                        _L
ZOOO
3000
4000
              »OC»
      >&.  OKJDES OF N ITROG-EN NtMissior45

    MOTORS AS  A FUNCTION OF  CRA/OKStt AFT RPH

   SIMULATED BOAT  UDAP  AS  DESCR\BED >W TABLES
                                                       5000
                                                FOUR OUTBOARD

-------
                                                                       20
exception is being made for outboards because significant amounts of
CC>2 are retained in the water phase, where CO2 may be of greater
importance.  The mass emissions rates shown in Figures  15 through 18
reveal few real surprises, but several items are worthy of note.  The
general increases in emission rates with engine speed and load are to be
expected, the only real exception being the small decrease in hydro-
carbons from the OMC 9. 5 hp engine above mid-speed.  It is possible
that the test engine was not typical in this respect because its fuel rate
and power output were slightly lower than expected, also.  Another
expected trend  was that the larger engines should produce more emis-
sions by mass than the smaller engines, and the only major departure
from this trend was the marked shift in CO emissions from the Mercury
65 hp engine  above 3000 rpm (Figure 16).  This shift shows a combustion
change, which was also noted in Figures 17 (slightly) and 18 (markedly).
For some reason the trapped  charge was burned much more completely
to CO2 above 3000 rpm,  resulting in higher cylinder pressure  and tem-
perature and the acceleration of NOX shown in Figure 18.  No dramatic
change in hydrocarbons was noted because most of the hydrocarbons in
the exhaust are due to  untrapped air/fuel mixture,  not partially-burned
trapped mixture.

       In addition to the gaseous emissions measured on a continuous
basis, light hydrocarbons were measured on bag samples by gas  chroma-
tograph and aldehydes were measured by wet chemistry.  The  light hydro-
carbon data are summarized in Table Sin terms of concentrations on a
wet basis, but  the "A" mode data  (after water scrubbing) have  not been
corrected to atmospheric pressure  by Henry's Law.  The same comments
apply to the data on formaldehyde (HCHO) and total aliphatic aldehyde (RCHO)
concentrations shown in Table 4.  Of the light hydrocarbons, the  only
compound absorbed strongly by the water was acetylene,  although several
of the others would show  smaller  losses in the water if mass-based com-
putations were made.  Both HCHO and RCHO (which includes formaldehyde,
of course) showed large losses in the water phase, as expected.   All the
light hydrocarbon and  aldehyde emissions could be computed on a mass rate
basis if it became desireable for some reason, but such a detailed analysis
is not considered necessary for this initial study.  The results given in
this subsection will be used in section V to estimate national outboard
emissions impact.

B.     Results of Tests Designed to Investigate the Water Scrubbing Process

       Having  analyzed several outboard motor emissions tests,  it seemed
that several  parameters  and variables  of the particular measurement
system used  may have had some effect on the changes in exhaust  gas com-
position during water contact.  Some of these items are water temperature,
absolute pressure at which the contact system is maintained, pH  of the
bubbling water  as  it enters the tank, bubble residence time in  the tank,

-------
                                                                        21
  (H2O/exhaust) ratio, bubble size, and turbulence in the tank.  Although
  no assertion is made that the system used for the subject tests represents
  the real situation (indeed,  in some instances  it definitely does not), at
  least the variations in most of the properties mentioned were either
  minimized or carefully controlled.  Throughout the regular tests on all
  the outboards and the special tests on the Mercury 650, the contact water
  temperature was relatively constant (nominal 66°F for the OMC 4 hp &
  Mercury 65 hp engines,  nominal 77°F for the other two); the tank head
  pressure was held  at 65 inches of water gage for all the engines except
  the OMC 9. 5, for which it was 50 inches (so absolute pressure varied
  only with atmospheric pressure and this variation was  corrected for by
  Henry's Law, where applicable);  the incoming water pH stayed between
  7. 2 and 7.4;  and bubble residence time (as a function of water depth) was
  held essentially constant.  Provisions were made for controlled variation
  of (H2O/exhaust) ratio, bubble size,  and turbulence, although these
  variations  were not necessarily independent of one another.   The (H^O/
  exhaust) ratio was  changed by holding the gas flow constant and varying
  the water flow, to yield  ratios by volume (70°F and 1 atm. ) of 2. 25,
  4.45, and 6.00.  The bubble size was varied by changing "bubbler" con-
  figuration and the turbulence was varied both by changing the water flow
  and by  switching the propeller off and on.

  TABLE 4.  AVERAGE CONCENTRATIONS OF FORMALDEHYDE (HCHO)
  AND TOTAL ALIPHATIC ALDEHYDES (RCHO) IN THE EXHAUSTS OF
FOUR OUTBOARD MOTORS BEFORE AND AFTER WATER SCRUBBING

  Mode   OMC   OMC     Chrys.    Merc.       OMC   OMC  Chrys.   Merc.
         4 hp    9.5hp   35 hp      65 hp        4 hp   9.5    35 hp     65 hp
   1      31     9.3      28          28          70     25     67       72
   1A     18     7.5      19          15          31     14     31       36

   2      32     14       17          38          52     38     52       58
   2A     18      5.9     15          16          35     14     28       58

   3      47     12       29          16          82     40     70       44
   3A     28      6.2     18          12          42     16     32       22

   4      46     38       53          27          92     66     138       55
   4A     21      9.0     23          10          37     15     47       19

   5      31     16       74          14          61     42     154       40
   5A     21      7.2     54          10          36     16     80       24

   6      20     14     125          30^          64     44     125       53
   6A     16     11       28          15          35     21     52       53

   7                                 21                                 44
   7A     -                           19          -      -      -        44

-------
           TABLE 5.   AVERAGE  CONCENTRATIONS OF LIGHT HYDROCARBONS
IN THE  EXHAUSTS OF FOUR OUTBOARD MOTORS BEFORE/AFTER WATER SCRUBBING
                                    Concentrations of Light Hydrocarbons by  Species, ppm
Mode   Engine

  1      OMC 4
        OMC 9. 5
        Chrys. 35
        Merc.  65

  2      OMC 4
        OMC 9. 5
        Chrys. 35
        Merc.  65

  3      OMC 4
        OMC 9. 5
        Chrys. 35
        Merc.  65

  4      OMC 4
        OMC 9. 5
        Chrys. 35
        Merc.  65

  5      OMC 4
        OMC 9. 5
        Chrys. 35
        Merc.  65

  6      OMC 4
        OMC 9. 5
        Chrys. 35
        Merc.  65
CH4
122/136
369/421
485/637
331/336
309/408
497/435
717/807
294/291
462/462
759/890-
1241/1313
323/311
439/442
1047/1307
1183/1369
1160/1390
769/1050
2260/2142
1810/1872
1590/1570
976/1010
1725/2317
2187/2193
1890/2080
C2H6
42/48
46/71
43/48
64/59
172/205
56/111
61/71
64/61
216/202
214/242
172/181
54/70
128/140
194/228
197/209
46/72
1 1 1 / 1 34
170/169
181/190
81773
118/114
168/224
246/268
117/125
C2H4
210/230
213/231
210/220
221/215
506/628
190/334
254/265
221/214
620/624
658/719
578/571
184/160
447/418
650/698
678/665
293/315
429/524
711/672
669/663
344/322
542/478
673/840
804/940
.491/483
C3H8
13/17
4/13
13/14
8/6
30/32
7/4
10/10
6/5
58/24
25/21
6/11
6/4
20/18
29/26
15/13
7/8
36/62
45/36
23/35
9/9
39/25
29/40
37/46
11/15
C2H2
102/59
161/88
203/111
118/55
106/92
72/50
339/164
102/39
262/116
306/137
562/286
131/44
314/213
732/518
615/263
808/417
888/578
1777/807
1370/611
1150/631
1024/690
1452/1033
1483/822
1370/648
C3H6
- / -
162/169
129/122
201/194
- / -
149/348
172/176
218/186
- / -
301/519
411/392
122/111
- / -
491/493
439/428
160/73
- / -
516/400
370/419
194/162
- / -
370/413
553/455
218/234
C4H10
304/317
169/243
183/239
396/395
268/320
101/261
155/179
370/380
335/307
259/340
171/196
278/275
334/248
320/359
187/168
419/512
400/614
661/601
399/514
563/513
635/558
457/649
563/684
578/721
        Merc. -65
                      2160/2220
118/121
574/528
19/20
1520/591
292/288
967/1030

-------
                                                                        23
        Figure 19 is a detailed view of the bottom of the bubbling tank
in the general configuration used for the special tests.  For the regular
tests, the propeller was not yet in place, and the "bubbler" (the pipe
protruding upward through the tank bottom to the left of the propeller)
was shorter and made a little differently.  Regarding the details of the
design, the propeller was a model airplane propeller shortened to 2
inches in diameter and having a pitch of 2. 125 inches, mounted 1  inch
above the bottom of the  tank and 11/2 inches from the bubbler on centers.
In operation, it was rotated at about 1650 rpm by an electric motor.

        The bubbler shown in Figure 19 was called the "sintered"  bubbler,
because it was made from a sintered  stainless steel filter element affixed
to a piece of tubing with epoxy (the axial center of the element was 2 inches
from the tank bottom).   The second design (shown later) was called the
"perforated" bubbler and was made of a piece of tubing with the end welded
shut and 4 small holes drilled in its wall at a point 2 inches from the tank
bottom.   The third bubbler (also shown later) was just a length of tubing
with an open end 2 inches  from the bottom of the tank.  The sintered bubbler
generated the smallest bubbles, the perforated one generated intermediate-
size bubbles, and the "tube"  (open-ended) bubbler generated the largest
bubbles.  The tube and sintered bubblers were used only during the  special
tests on the  Mercury 650, but the perforated bubbler was used for the
regular tests on the OMC  9. 5 and Chrysler 35 engines, and the bubbler used
for  regular tests  on the other two engines was similar to the perforated unit
except that the holes were less than 1/2 inch from the tank bottom.

        Continuing with descriptions,  Figure  20  shows the tube (open-ended)
bubbler installed in the  tank.  This figure  also  shows typical bubbles gen-
erated by the tube bubbler with the propeller off and at the lowest water
flow rate (H2O/exhaust  ratio =  2.25).  Figure 21 shows bubbles generated
by the perforated bubbler  at the same  conditions, and although the photo-
graph is not very clear the bubbles  seem about the same as those in Figure
20.  Figure  22 shows bubbles generated by the sintered bubbler,  again
with the lowest water flow and the propeller off, and the difference between
this bubbler  and the other two is quite apparent.

       Figures 23 and 24  were taken with the tube bubbler in place, and
with the  lowest water flow rate, but the propeller was "off" in Figure 23
and  "on" in Figure 24.   Figures 23 and 24 were taken by available light with
the camera hand-held, while the earlier bubbling tank photos were taken with
an electronic flash.  The earlier photos have better depth of field and detail,
but the latter (with a shutter speed of 1/2 second or so)  show what the bubbles
were doing much more clearly. The effect of the propeller on turbulence in
the mixing region is clearly in  evidence in Figure 24.

       Figures 25 and 26 were taken with the perforated bubbler in place
and back lighting using an incandescent lamp. The camera was again hand-
held and a long exposure was used.  The water/exhaust ratio in use was 4.45

-------
                                                                              24
Figure 19.  Close-up Detail of Tank    Figure 20.  Tube Bubbler With Lowest
Bottom with Propeller and Sintered     Water Flow Rate and Propeller Off
Bubbler Installed
Figure 21. Perforated Bubbler with
Lowest Water Flow Rate and
Propeller Off
Figure 22.  Sintered Bubbler with
Lowest Water Flow Rate and
Propeller Off

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                                                                              25
Figure 23.  Tube Bubbler with Lowest
Water Flow Rate and Propeller Off
Figure 24.  Tube Bubbler with Lowest
Water Flow Rate and Propeller On
  Figure 25.  Perforated Bubbler with
  Intermediate Water Flow Rate and
  Propeller Off
Figure 26.  Perforated Bubbler with
Intermediate Water Flow Rate and
Propeller On

-------
                                                                        26
 and the propeller was "off" in Figure 25 and "on" in Figure 26.  Again
 the effect of the propeller was quite pronounced. Similar attempts were
 made at taking photos using the sintered bubbler and the three water
 flow rates, but the propeller did not seem to make  as much difference in
 these cases.

        The conditions used during the 9 special tests are summarized in
 Table 6  for reference, and these tests were limited to modes 1,  3,  5, and
 7 of those  used for the regular tests on the Mercury 650.  For the special
 tests only,  modes designated "A" were samples taken after bubbling and
 with the propeller off,  and modes designated "B" were  samples taken after
 bubbling and with the propeller on.  In order to minimize the effect of drift-
 ing^each  mode consisted of seven sampling conditions in sequence.  This se-
 quence was (1) raw exhaust;  (2) bubbled exhaust with propeller off;  (3)
 bubbled  exhaust with propeller on;  (4)  raw exhaust;  (5) same as (3);  (6)
 same as (2);  (7) same as (1). The results reported on pages D-7 through
 D-10 of  Appendix D are concentrations on a wet basis representing  averages
 of 3 samples for raw exhaust and 2 samples each for "A" modes and"B" modes,
 with sequence  as indicated above.   The concentrations have not been subjected
             TABLE 6.   CONDITIONS USED  FOR SPECIAL
         TESTS OF THE MERCURY 650 OUTBOARD MOTOR

       Special                H?.O/Exhaust  	Propeller	
        Test    Bubbler         Ratio      "A" Modes   "B" Modes
          1     sintered         2.25          off           on
          2     sintered         4.45          off           on
          3     sintered         6.00          off           on

          4     perforated       6.00          off           on
          5     perforated       4.45          off           on
          6     perforated       2.25          off           on

          7     tube             2.25          off           on
          8     tube             4.45          off           on
          9     tube             6.00          off           on


to the Henry's Law correction, but the percentage losses to be presented in
text have been corrected.  Table 7,  then, gives losses of HC, CO, CO2, NOX,
and  Oo as percentages of their respective totals in  raw exhaust gas.  Such a
table is quite difficult to interpret if examined as a whole, so the effects of
several pertinent variables will be examined graphically.  To make the best
possible use of such data, an analysis of variance should be performed by
computer, but this step has not been taken.

       Figure 27 shows the apparent effect of (H2O/exhaust) ratio on
losses of hydrocarbons from the exhaust gas to the  water, indicating that
higher ratios are associated with greater removal of hydrocarbons.  The

-------
       TABLE  7*   PERCENTAGE LOSSES OF EXHAUST GAS  CONSTITUENTS
          DURING WATER CONTACT IN SPECIAL TESTS ON MERCURY 650
                            Losses as Percentages of Total Amounts Present in Raw Exhaust
"A" Modes of Special Test (propeller turned'bff")
Gas
HC



CO



C02



NOX



°2



Mode
1
3
5
7
1
3
5
7
1
3
5
7
1
3
5
7
1
3
5
7
1
27. 0
36. 1
25. 1
18.8
3. 88
7. 12
0.80
4. 04
34. 4
32. 2
30.3
32. 1
16.4
7.29
62. 3
69.5
0. 64
1.16
0.64
1.66
2
31.9
39.4
30.7
31. 2
5.81
5. 55
2.69
6.47
39.6
42. 0
31.9
28.0
11. 3
12.3
71.0
9.48
-0. 52
-8. 17
0. 27
4.35
3
44. 6
41.3
32. 1
25. 5
5. 18
1. 16
5.84
6.33
58.7
46.8
43.8
45.6
20. 3
17.6
31. 1
70. 1
0. 62
-1. 52
0. 92
3. 23
4
39. 1
36.7
31.4
21.3
6.65
7.49
4. 96
4. 25
53.6
57.6
47. 3
39. 1
9.63
15.8
71. 1
69.7
-1.52
-3.64
0. 70
3. 06
5
30.6
31.8
23. 1
18. 5
4. 34
5.24
2.47
5. 25
33. 7
34. 5
23.9
24. 1
5.96
2. 73
62.2
69.7
-0.86
-2.84
-0. 25
-0. 09
6
22.6
29.8
23. 1
13.0
5.64
7.81
3.22
2.46
18. 9
22.4
20. 9
15.6
-0. 70
16.9
49.6
54. 0
2.64
-1. 17
2. 22
1.36
7
22. 1
27. 7
20. 6
19.4
3. 34
3.31
3.40
-0. 93
16.6
16.6
16.3
15.2
7. 15
4. 39
70.8
69.6
10.6
3.87
-0.73
1. 02
8
29.8
32.5
28.5
16.8
9.79
4.39
4. 41
3.79
28.4
29.3
29.5
25.3
9.53
6.91
50. 6
69.7
-1. 21
0.20
-0. 27
2.74
9
35.4
37.8
32. 2
27. 2
5.28
4. 77
6.52
6.88
49. 0
44. 7
46.3
39.4
12.0
15. 3
63.3
70. 5
-2.84
-5.48
2.31
2. 04
Table 7 continued on next page.
                                                                                                                      C\>

-------
TABLE  7. (Cont'd). PERCENTAGE LOSSES OF EXHAUST GAS CONSTITUENTS
       DURING WATER CONTACT IN SPECIAL TESTS ON MERCURY 650
                      Losses as Percentages of Total Amounts Present in Raw Exhaust
"B" Modes of
Gas
HC



CO



C02



NOX



°2
£


Mode
1
3
5
7
1
3
5
7
1
3
5
7
1
3
5
7
1
3
5
7
1
30.
39.
28.
20.
5.
2.
2.
5.
43.
40.
39.
30.
20.
14.
50.
69.
1.
-0.
1.
2.

7
8
5
9
51
06
82
29
6
5
4
9
2
5
3
7
81
19
60
29
2
35.6
40. 7
36. 1
21. 5
1.81
8.68
4.21
7. 04
45. 6
47.8
47. 1
36.7
13. 2
10. 3
71.5
85. 0
1.72
-4.52
1.83
4.72
3
43. 5
43. 7
37. 1
26. 1
1. 49
7. 12
6.98
7. 16
54.8
57.0
55.8
50.8
17. 7
16.3
66.0
70. 2
-2.85
-2. 27
1. 04
2.67
4
40.7
41. 7
32.9
22.5
4.68
5. 18
5.41
6.43
54. 2
60.6
52.9
46. 1
16. 4
23. 0
71. 2
69.9
1.96
-3. 10
1. 18
3.50
Special Test (propeller turned "on")
5
36.
36.
27.
20.
5.
11.
2.
3.
46.
39.
41.
30.
3.
6.
50.
69.
2.
-1.
1.
-4.
0
9
2
8
55
3
80
64
4
7
0
7
15
16
5
7
24
53
24
22
6
28. 6
.36.2
26.3
15.5
4.66
0. 34
2.94
3. 55
28. 6
31.9
27. 5
25.7
9. 64
15.7
50. 0
69.6
-3. 19
-0.35
2.88
2. 04
7
27.6
33,8
25.0
21.0
3. 40
0. 58
3. 49
11.0
26.9
27.2
25.8
23.8
9. 10
13.9
56.7
69-9
11. 7
5.00
0.44
1.99
8
33. 2
36.9
32.3
17.2
4.49
5. 52
5.63
2.83
41. 1
38. 6
41.6
26. 1
13. 7
8. 16
51.3
69.7
1.65
3. 16
2. 27
1.91
9
37. 0
40. 5
33.9
27.7
6.31
6. 70
6.67
6.56
52.4
59.3
49. 4
38. 0
12.6
15.9
63.4
70. 5
1.22
-3.42
0. 14
2.93
                                                                                                        IV
                                                                                                        00

-------
                                                                29
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2
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o
5

e>
2

QC
O
a




-------
                                                                       30
values plotted were obtained by averaging the 12 applicable numbers
(3 bubblers x 4 modes), with the propeller off and the same with the
propeller on. Since the 4 modes are being averaged together,  the num-
bers are not particularly representative of the real situation,  so it could
be said that the  engine was  being used as a fairly repeatable gas genera-
tor for the special tests. In naming Figure 27 and several later graphs,
the term "apparent" effect is used because it is simply not certain that
the change in the dependent variable shown is due (either entirely or in
part) to change in the  independent variable.  Within reasonable limits,
for instance, the change in  hydrocarbon removal observed could be due
to water turbulence rather than flowrate, but the (H2O/exhaust) ratio can
be assigned a number much more readily.  These same general comments
are equally applicable to Figures 28 and 29, which show the apparent
effect  of water flowrate  on losses of CC>2 (Figure 28), and O2 a^d CO
(Figure 29). A  comparable figure was not constructed for NOX due to
the extremely large variation in NOX between modes, which would have
created misleading averages.

        Figure 30  shows the apparent effect of raw exhaust concentrations
on losses of HC, COo. and  NOX in the bubbling  system.  The effect shown
for CC>2 is probably due simply to  concentration,  but those shown for HC
and NOX are probably due more to changes in the composition of the classes
of compounds.   Hydrocarbons, for instance, probably are composed of
larger fractions of unburned fuel and smaller fractions of combustion pro-
ducts as their overall concentrations increase,  which could lead to lower
fractional losses as concentrations increase.  Oxides of nitrogen are pre-
dominantly NO at higher concentrations,  but can contain substantial fractions
of NO2 at low overall  concentrations.   The NO is not very soluble,  but NO2
dissociates in water,  and thus is removed readily by water, and it is this
effect -which probably  leads to the relationship for NOX shown in Figure 30.

        It is quite  clear that much additional analysis could be performed
on these data, and that only a modest start has  been made, but more ex-
tensive analysis is outside the scope of this project at least for the present.
A good place to  begin  from  here is probably the analysis of variance
suggested earlier.  No serious attempt has been made to evaluate changes
in composition of the water going through the contact system by direct
measurement.   The preliminary studies on this subject which have been
conducted indicate that most process-type water analysis methods do not
have the sensitivity required for good quantitative results, and that more
sensitive techniques are very laborious and/or expensive.

C.      Results of Emissions Tests on the Chrysler 35 hp  Outboard
        Motor Using a  3rd Order Power Curve

        The  test results  on the Chrysler 35 hp engine which were presented
in Section IV. A were generated while  the engine was running on a  2.5
order power curve, which is considered most typical for this  engine in

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-------
                                                                  33
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                                                                        34
  pleasure boat service.  In addition to the five runs using the 2. 5 order
  power curve,  however, two runs were made using a 3. 0 order curve,
  which reduced the power output somewhat in Modes 2, 3, 4, and 5.
  Mode 1 (maximum power) would have remained the same,  so it was not
  run;  and Mode 6 (idle) would likewise not have changed,  so it was not
  run.  The crankshaft and propeller shaft power points were given in
  Tables  1 and 2,  so they will not be repeated here.

          Table  8 gives mass emissions data on a 3.0 order power  curve
  analogous to those found in Table 3 for the four engines operated on
  power curves  considered "normal".  The data in Table 8 have already
  been plotted (curves labeled x = 3 for the Chrysler in Figures 15 through
  18),  and they  compare quite closely with those generated using higher
  loads.  Differences in NOX and CC>2 were so small as to be almost  negli-
  gible,  but CO was higher and hydrocarbons were lower at the higher
  speeds when power output (and consequently mass flow) were reduced.
TABLE 8.  TOTAL MASS EMISSIONS .AND MASS EMISSIONS RETAINED IN
WATER PHASE (EXPERIMENTALLY) FOR A CHRYSLER 35 HP OUTBOARD
          MOTOR OPERATED ON A 3. 0 ORDER POWER CURVE
            x
Gas

 HC
 CO
 CO2
 NO
 °2
 H2O
         Gas

         HC
         CO
         C02
         NOX
         H20
                      Raw Mass Emission Rate, g/hi
                 Mode 2
Mode 3
Mode 4
Mode 5
1640
6340
9720
6.32
3140
8430
Loss in
Mode 2
613
299
3910
2.78
- 21.5
6740
1340
4350
6580
3.60
2510
5770
1080
2580
3870
1.44
2240.
3230.
880
1140
1840
0.64
1700
1580
Water (Experimental), g/hr
Mode 3
496
239
2690
1.99
- 148
4570
Mode 4
426
205
1640
0.94
32.0
2490
Mode 5
328
74.5
796
0.54
38.6
1180
         The trend reversed itself at lower speeds for hydrocarbons, but
  remained the same for CO.  If emissions were to be studied as a function
  of load at fixed speeds, a wider range of loads would be necessary to get
  meaningful variation.  For the purposes of the present study, however,
  the limited amount of work performed with the one engine indicates that
  mass emissions probably do not vary strongly over the range of power
  outputs to be expected at one crankshaft speed.

-------
                                                                   35
    V.  ESTIMATION OF EMISSION FACTORS AND NATIONAL IMPACT

       The quantities essential to determining emission factors for out-
boards are mass-based emissions data and information on duty cycles
(fractions of operating time spent in various speed  bands).  Estimation of
national impact further requires data  on annual usage, number of motors
in service, and composition of the population of motors according to size.
It is also relatively simple to calculate emission factors on a fuel basis,
but use of these factors in determining impact requires the assumption
of national fuel usage, not a readily documented quantity.  It any case,
fuel-based factors will be calculated and the corresponding impact
analysis will be attempted, based on available information

       As  discussed in the section on results, outboards actually dis-
charge their  exhaust underwater, so measurements were taken both before
and after the exhaust was bubbled through water in  a simulator in an
attempt to  take the water scrubbing process into account.  In this context,
outboard "atmospheric" emissions means the portion of total outboard
emissions  which made its way through the bubbling process without
being retained in the water.  No assertion is made  that the laboratory
process takes into account the time factor which exists in the real situa-
tion, that is, the subject work has involved no attempt to determine the
ultimate fate of exhaust products.  This assumption of a static situation
is undesirable, but nevertheless necessary in lieu of experimental data.

A.     Development of Emission Factors

       The emissions data on which the factors will be based are given
in section IV. A.  It would be more desirable,  of course, to be able to base
emission factors on a greater number of engines, but additional data are
simply not available.  The other major items of information required are
duty cycles for outboards, expressed  in fractions of time spent in each
attainable speed band.  Data developed by Outboard Marine Corporation
in a rather extensive outboard motor usage survey' ' are shown in Table
9, representing about 200 hours of data acquisition. The "100 hp and up"
engine category included three engines, the 50-55 hp category included
three engines,  the 40 hp data  are from a single engine, and the 9. 5 hp
data represent four engines.  To make the best use of these  data, they
have been regrouped on larger rpm intervals corresponding  to the engine
speeds used for testing,  and are presented as Table 10. The OMC data
developed on the  9. 5 hp engines was used  to determine mode weights for
both the 4 hp and 9. 5 hp test engines,  an average of OMC data developed
for 50-55 hp  engines and 9. 5 hp  engines was used to determine mode
weights for the Chrysler 35 hp engine, and the OMC data on  50-55 hp
engines was used alone to determine mode weights  for the Mercury 65

-------
                                                                   36
      TABLE 9.  OMC OUTBOARD MOTOR OPERATING TIME DATA
Rpm Range
 500-
1000-
1500-
2000-
2500-
3000-
3500-
4000-
4500-
5000-
5500-
1000
1500
2000
2500
3000
3500
4000
4500
5000
5500
6000
                Percent of Operating Time in rpm Range by Engine Size
100 hp & up
30
15
5
3
3
8
12
18
4
2
_
50-55 hp
7
17
10
7
4
8
13
23
5
4
2
40 hp
3
13
12
7
3
13
13
19
12
5
_
9. 5 hp
8
12
10
10
6
13
12
16
11
2
_
   TABLE 10.  TIME-BASED WEIGHTING FACTORS FOR TEST MODES
 Mode

  1
  2
  3
  4
  5
              Fraction of Operating Time in Modes by Engine (Wj)
OMC 4 hp
0. 21
0. 20
0. 19
0. 20
0. 10
0. 10

OMC 9. 5 hp
0.21
0.20
0. 19
0.20
0. 10
0. 10

Chrysler 35 hp
0. 12
0. 32
0. 15
0. 18
0. 12
0. 11

Mercury 65
0. 06
0. 05
0. 36
0. 12
0. 17
0. 12
0. 12
hp







 hp engine.  To make the arithmetic of the emission factor calculations
 more compact,  a few terms should be defined.

        let:  Wj = individual time-based mode weighting factors;
             MI = individual mode mass emission rates (g/hr);
             hpi = crankshaft horsepower  developed in individual modes;
               n = number of modes (6 or  7)

 Using these terms to compute emission factors, we have
                                                   n
        composite (cycle) mass emissions (g/hr) =  y      W^^ ;
                                                 •i  =  l
                                                 i =  1
                                                                n
        average crankshaft power developed during cycle (hp) =   )    Wj

                                                              i = 1

-------
                                                                    37
                                                        n
       composite brake specific emissions /  g
                                             ~
                                                        n
                                                       i =  1

       composite load factor -  average power used (hp) _
                                maximum power available (hp)
                                  n
                                 E
                                 i - 1
                                Maximum rated power (hp)

 If it were desirable to compute fuel specific emissions for some reason,
 assuming that

                Fj  = individual mode fuel rate (gal/hr),
                                                        n
 then                                                   v~~v  w K/I-
                                                       .E    ''
       composite fuel specific emissions (g/gal fuel) =
                                                       n
                                                       E   w'Fi
                                                      i =  1

and                                         n
                                           r—\  W-F.
       composite brake specific            /—>
       fuel consumption (gal fuel/hp hr) =   x =
                                            n
Individual mode brake specific emissions and fuel specific emissions
would be given by M^/hpi and Mi/ F^, respectively.
       Table 11 shows the procedure for calculation of composite (cycle
average) power outputs and load factors, and Table 12 gives the procedure
for calculation of composite fuel consumption and composite brake
specific fuel consumption.  These calculated quantities can be used in
conjunction with the sums of the weighted mass emissions for each
engine to determine the composite brake specific and fuel specific

-------
                                                                   38
                TABLE 11.  COMPOSITE POWER OUTPUT
                   AND LOAD FACTOR CALCULATIONS
Mode

  1
  2
  3
  4
  5
  6
  7

Composite Power Output (hp)
                                  Weighted Crankshaft Power Output
                                        by Engine
OMC
4 hp
0.84
0.56
0.23
0.07
0.01
0.00

OMC
9.5 hp
2.00
1.42
0.66
0.25
0. 02
0.00
-
Chrysler
35 hp
4.20
6.40
1.47
0.63
0. 07
0.00
-
Mercury
65 hp
3.90
2.66
12. 13
1.79
1. 02
0. 13
0. 00
            n
           E
            =  i
1.71
4. 34
12.77
21. 62
 Composite Load Factor
       n
     i =  1
     maximum power
                                0.427   0.457
                  0.365
                     0. 333
emissions.  The  steps leading to these specific emissions results are
outlined in Table 13,  and the composite specific emissions listed are
those which will be used in estimating national impact.  It has been noted
previously that the regular tests on the four outboards were performed
using a variety of combinations of water:exhaust gas ratio and induced
turbulence.  In order to avoid the confusion this variation might cause,
the combination will be "standardized" for the purposes of the emission
factor calculations as:  (1) perforated bubbler; (2) water:exhaust gas ratio
4.45:1; and  (3) propeller "on".  This combination was used for tests on
the Chrysler 35 hp and Johnson 9. 5 hp motors, but not for the other two,
so consideration  has been given to modification of the measured losses
in the water phase for the Johnson 4 hp and Mercury 65 hp engines.  This
consideration  has lead to the arbitrary decision that the measured CO2
and HC losses for the Johnson 4 hp motor should be multiplied by 1.18

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                                                                  39
             TABLE 12,   COMPOSITE FUEL CONSUMPTION
                      AND BSFC CALCULATIONS

                                  Weighted Fuel Consumption by
                               	Engine (WjFi) gal/hr 	
Mode

 1
 2
 3
 4
 5
 6
 7

Composite Fuel Consumption
              n
(gal/hr)  =
 £
i. i
                   0. 139
                   0.090
                   0. 059
                   0.040
                   0.016
                   0.016
         OMC
        9.5 hp

        0. 277
        0.239
        0. 188
        0. 128
        0.033
        0.028
0.360   0.893
Chrysler
  35 hp

 0. 503
 0.890
 0.300
 0. 224
 0. 080
 0.081
 2.077
Mercury
 65 hp

 0.451
 0. 302
 1.444
 0. 332
 0. 331
 0.206
 0. 148
  3.215
Composite BSFC (gal/hp hr)
        n
       £  WiFi
      i =  1
        n
                               0.211   0.206
                                      0. 163
                               0. 149
and those for the Mercury 65 hp motor by 1. 05.  The decision is based
on differences in CO2 losses for the four engines, and will be assumed to
apply only to CO2 and HC since for NOX  and CO losses in water, no strong
dependence on turbulence has been established.

       It is  conceded that the choices made in determination of factors
have been arbitrary, but consider the following  rationale:

(1)     It has been established in the special tests of the Mercury 650
       that losses of condensable and/or soluble exhaust constituents
       in the water phase exhibit a positive dependence on some
       combination of water:exhaust ratio and turbulence.

(2)     It has been established that losses of exhaust products in the
       water phase  can be significantly greater than those assumed

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                                                                   40
        for calculation purposes (if turbulence, etc. ,  are varied).

 (3)     The real situation very probably entails a combined index of
        water:exhaust ratio and turbulence at least as high as that
        assumed for calculation purposes.

 (4)     Other variables which may have some effect on removal of
        exhaust constituents during water  scrubbing,  such as water
        temperature,  bubble residence time (as a function of depth),
        and water pH, were documented in the subject studies as
        being within reasonable ranges which might be encountered
        in the field.

 Thus the choices made constitute a "middle of the road" approach which
 is justified by the overall limits of the study,  and indeed some choices
 had to be made before any results could be determined at all.  No
    TABLE 13.   INDIVIDUAL AIR AND WATER BRAKE SPECIFIC AND
  FUEL SPECIFIC EMISSION FACTORS FOR FOUR OUTBOARD MOTORS

               Composite Factors,Atmospheric  Composite Factor, Water Phase
                                     Fuel                           Fuel
                           Brake    Specific,              Brake    Specific,
         Consti-  Mass,    Specific,  g/gal     Mass,      Specific,  g/gal
Engine   tuent     g/hr     g/hp hr   fuel        g/hr      g/hp hr   fuel
OMC
4 hp *••


*HC
CO
*C02
NOV
195.
413.
871.
1.24
114.
241.
509.
0. 72
OMC
9.5 hp


HC
CO
C02
NOX
393.
1280.
2140.
2. 34
Chrysler  HC
35 hp     CO
          C02
 991 =
4010.
4240.
   2.97
Merc.
65 hp


**HC
CO
*#CO2
NOX
1780.
4090.
7740.
14.2
                                      542.
                                     1150.
                                     2420.
                                        3.4
 90.6    440.
295.     1430.
493.     2400.
  0.53      2.6

 77.6    477.
314.     1930.
332.     2040.
  0.23      1.4

 82.5    555.
189.     1270.
358.     2410.
  0.65      4.4
 102.          59.9     284.
  53.7        31.4     149.
 574.         336.     1590.
   0.34        0.20     0.95

 302.          69. 6     338.
  68.2        15.7      76.4
1460.         336.     1630.
   0.26        0.060    0.29

 627.          49.1     302.
 208.          16.3     100.
2640.         207.     1270.
   1.37        0.11     0.66

 889.          41.1     277.
 139.           6.45    43.4
5680.         262.     1770.
   2.44        0.11     0.76
 Calculated loss in water multiplied by 1. 18 to achieve these results
**calculated loss in water multiplied by 1. 05 to achieve these results

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                                                                   41
assertion is made that the chosen results actually represent the real
situation, but they do constitute a reasonable estimate.

       The most notable feature of the data given in Table 13 is the
extremely good consistency of the brake specific and fuel specific emis-
sions from engine to engine, considering the variations in size and
general physical configuration.  The consistency is even better if
variations in the effects of water scrubbing are removed by combining
the atmospheric and water factors to yield the total emission factors,
as has been done in Table 14.  The only major variations in these data
occur in NOX (which was present in very small amounts and exhibited
large concentration variability), and in CO-COz balance for the Chrysler
(which was weighted much more heavily toward CO production than was
the case for the other  3 engines).

TABLE 14.  TOTAL EMISSION FACTORS  FOR FOUR OUTBOARD MOTORS
             (Combined Atmospheric and Water Phase Factors)
 Engine

 OMC 4 hp
Constituent    Mass, g/hr
 OMC 9. 5 hp
 Chrysler
 35 hp
 Mercury
 65 hp
   HC
   CO
   C02
   NOX

   HC
   CO
   C02
   NOX

   HC
   CO
   C02
   NO
                    x
   HC
   CO
                 NO
                    x
  297.
  467,
 1440.
    1. 58

  695.
 1350.
 3600.
    2, 60

 1620.
 4220.
 6880.
    4. 34

 2670.
 4230.
13400.
   16.6
Brake Specific,
 g/hp hr	

   174.
   273.
   845.
     0.92

   160.
   311.
   829.
     0.60

   127.
   330.
   539.
     0.34

   123.
   196.
   620.
     0. 77
Fuel Specific,
 g/galfuel

  825.
 1300.
 4010.
    4. 39

  778.
 1510.
 4030.
    2.91

  779.
 2030.
 3310.
    2.09

  830.
 1320.
 4170.
    5. 18
       These emission factors do not include crankcase drainage, which
is a mixture of fuel-based (liquid and gaseous) hydrocarbons and air
emitted from the crankcases of some outboard motors.  For the test
engines in particular,  two (Mercury 65 hp and OMC 9. 5 hp) had drain
recirculation,  one did not (Chrysler 35 hp),  and the last (OMC  4 hp)
could not be verified one way or  the other.   Exhaust emissions from the

-------
                                                                   42
engines with recirculation correctly characterize their total emissions,
whereas crankcase drainage would be considered separately for engines
without recirculation.  There are several possible effects on total
emissions due to un-recirculated crankcase drainage.

       (1)   Fuel which drains from the crankcase may be  incorrectly
             included as part of the  total fuel used to calculate mass
             emissions, making the calculated mass  emissions higher
             than actual.

       (2)   It might be possible in  some engines to measure exhaust
             emissions at a point far enough downstream such that
             the inducted mixture and the drainage would have already
             mixed.  This type of sampling would give accurate
             results  if all the drainage had vaporized, but would
             probably not be accurate if part of the drainage were
             still liquid.

       (3)   One technically correct way of dealing with the drainage
             would be to measure it on a mass basis  (including con-
             densable hydrocarbon vapors), and subtract it from the
             externally-measured fuel consumption before calculating
             mass emissions.  The  drainage measured could then
             simply be added to the  total hydrocarbon emissions
             without  affecting the other  constituents.

       The possible ramifications of the crankcase drainage situation
simply had not been considered before the subject tests were run, so the
results given here will be for raw exhaust not mixed with drainage, and
the fuel rates used for mass emissions will be the externally-measured
fuel rates.  Based on the results of the companion study on  crankcase
drainage currently being conducted,  the probable errors inherent in the
less-than-rigorous procedures  used here are a fraction of a percent for
the Chrysler 35 hp engine and a few  percent (perhaps 2 or 3 percent) for
the OMC 4 hp engine  (if it does  emit drainage at all).   These percentages
are for cycle composite emissions,  with the larger probable errors
occurring at low speeds and the smaller ones at high  speeds,

B.     Estimation of National Impact

       The primary source of outboard  motor population and utilization
data at the present time is the Boating Industry Associations (BIA)(4).
Other industry sources^5'^ help to fill in the short-term historical
picture,  but  most of the statistics given are oriented  toward industry
economics rather than population and usage.  A summary of the major
usable population and sales statistics(4' 5) is given in Table 15, including
an assumption(^) of average motor horsepower for the years before 1949.
The report just  referenced  contains  some very useful calculations on

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                                                                    43
TABLE 15. SUMMARY OF OUTBOARD MOTOR POPULATION AND SALES DATA
Percentage

Year(s)
1919-1930
1931 1941
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
I960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
Sales
x 10-3
357.4
775
398
584
499
329
367
284
337
463
479
515
642
550
504
540
468
343
360
362
390
393
440
444
500
510
430
495
0-
6.9


7. 0-
19.9


-1942-1945


















36
27
22
17
17
16
17
17
19
21
19
25
28
29
28
27
22


















48
47
42
40
34
27
25
25
24
25
38
30
23
21
19
22
19
of Sales by hp Class
20.0- 20.0 45.0
44. 9 & up & up



No Production














— ••


















16
26
36
43
49















57 	
39
38
35
30
19
21
22
21
19
21
19
19
20
22
24
24
24
27
29
34
30
40
Avg.
hp Sold
i
t
5.0
(Assumed)
4
6.4
6.9
8.9
8.4
9.0
10. 3
12.9
14. 2
16.3
20. 7
23.7
27.4
29.9
30.3
30.5
30. 3
28.2
29.9
30. 1
31. 5
33. 1
31. 0
35.6
Outboard
Motors
in Use x 10

_



2643
2811
3010
3219
3419
3740
4210
4700
5040
5385
5650
5800
6100
6244
6390
6564
6645
6784
6904
6988
7101
7215
7300
 an outboard motor population model, and the one which seems to fit the
 available data fairly well is
                                                        2
         fraction of motors of age  "A" still in use _  e"kA  = Fj  ,

 where k = 20 83xlO"3 yr~^ and A =  motor age in years.  Using this ex-
 pression and designating individual motor ages as Aj,  the current motor
 population is

        sum of motors still in use =
                                    J =

-------
                                                                   44

where n = number of years backward over which the analysis extends and
Nj = number of motors sold in each individual year.  The reportC7) verified
that the above model gave reasonable approximations of the actual I960
and  1965 motor populations when applied over the time  spans prior to those
years.  In addition,  the 1949 motor population was calculated using the
model for additional verification and the prediction was within 5% of the
value for 1949 listed in Table 15,

        The application of the population model which is of most interest
in this study is in calculation of the average power  of engines in the field.
The calculations  leading to the  desired  result are summarized in Table 16
(where hpj = average power of motors sold during each individual year),
and the average power computed is
                             n
                            E
         average power =   J = 1	   = 24, 6 hp
                             n

                            I   «!
                           J =1

If all engines produced prior to 1946 are neglected, the average power is
slightly higher but still rounds to 24. 6 hp.  Just to make sure the above
estimate was reasonable,  a  much less accurate approximation was cal-
culated by assuming that the 7. 3 million newest motors were those still in
use at the end of 1971.  This approximation yielded an average power  of
27. 0 hp, indicating not only  that the more soundly-based estimate is
reasonable, but also that the older motors  play only a minimum role in
determining average power of engines in the field.

      Another important use of the data in  Table 15 is in formulating an
estimate of the percentage of motors which fall into each of the four (more
modern) power categories.  The process here will be to calculate the  sur-
viving population in each power category by weighting each year's total
surviving  population (S;) by fraction produced in each power category.   From
I960 back to 1955,  it will be assumed that the "20 hp  & up" category is
composed 75% of "20. 0-44. 9 hp" motors and  25% of "45 hp & up" motors.
Prior to 1955,  the "20 hp & up" category will be extrapolated linearly to
zero over a period of four years, assuming an  average of 25 hp.  Again
prior to 1955, it will be assumed that engines in the "0-6. 9 hp" category
averaged 5 hp,  and that those in the "7.0-19. 9  hp" category averaged  15 hp.
These assumptions permit the calculations to be extended back to the earliest
available data,  as shown in Table 17 along  with the results of the calculations.

       Having arrived at the population breakdown shown at the bottom of
Table  17,  most of the information required for the impact calculations
has been developed, with one of the exceptions  being average  annual

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                                                              45
   TABLE 16.  SUMMARY OF CALCULATIONS LEADING TO AVERAGE
     POWER OF OUTBOARD MOTORS IN USE AT THE END OF 1971
Year(s)
         Age -
Sales=N
(xlO-3)
                                 J
Surviving Motors
    FjNjtxlO-3)
   Power of
Surviving Motors
= Sihpi(xlO-3), hp
1919-1930
1931-1941
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
I960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
*46. 5
*35
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
*0. 00222
*0.0312
0. 171
0. 196
0. 224
0. 254
0.287
0. 322
0. 360
0.400
0.441
0.485
0. 529
0. 574
0.620
0.665
0. 710
0. 754
0. 795
0. 834
0. 871
0.903
0.932
0.956
0. 975
0. 989
0.997
1.000
357.4
775
398
584
499
329
367
284
337
463
479
515
642
550
504
540
468
343
360
362
390
393
440
444
500
510
430
495
0. 793
24. 2
68. 1
114.
112.
83.6
105.
91.4
121.
185.
211.
250-_18. 5%ile
340.
316.
312.
359.
332.
259.
^;-48.7%Ue
340.
355- 62. 3%ile
410.
424- 73. 8%ile
488.
504-_87. 3%ile
429.
495.
3.97
121.
340.
570.
560.
535.
724.
813.
1020.
1660.
2170.
3220.
4830.
5150.
6460.
8510.
9100.
7740.
8670.
9210
10300.
10000.
12300.
12800.
15400.
16700.
13300.
17600.
                             E-
              7317.
                      179700.
 Neglecting 1919-1941
  E
   7292.
    179600.
 *Median value for the range of years assumed.

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                                                                46
TABLE 17.  SUMMARY OF CALCULATIONS LEADING TO FRACTIONS
 OF OUTBOARD MOTORS IN SERVICE IN FOUR POWER CATEGORIES
                    Surviving Motors in Horsepower Category xlO"3
Year(s)
1919-1930
1931-1941
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
I960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
0-6. 9
0.793
24. 2
68. 1
114.
112.
71.9
85.0
55.8
84.7
126.
124.
90.0
91.8
69.5
53.0
61.0
53. 1
44.0
48.6
57.4
71.4
67.4
102.
119.
142.
141.
116.
109.
7.0-19.9





11.7
20.0
35.6
31.5
44.4
61.2
120.
160.
133.
125.
122.
89.6
64.8
71.5
72.5
85.0
135.
123.
97.5
102.
95.8
94.4
94,0
20.0-44.9








4.84
14.8
25.3
30.0
66.3
85.3
101.
132.
142.
101.
109.
106.
102.
67.4
86. 1
93.3
102.
95.8
90. 1
94.0
45 & up











10.0
22. 1
28.4
33.5
44.0
47.3
49.2
57.2
66.4
81.6
85.2
98.4
114.
142.
171.
129.
198.
   Total
2303.
                                1990.
                            1648.
            1377.
   Fraction of Total   0.315
                 0.272
0.225
0. 188

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                                                                   47

usage.  No credible usage data are currently available, so estimates of
50 hours per year for an outboard motor'  ' and 75 hours per year for an
outboard boat(^) will be considered.  Assuming that there were 7. 3
million outboard motors in use at the end  of 1971, the above estimate
of motor usage yields 365 million motor hours per year.  The latter
estimate of 75 boat hours per year combined with an industry figure for
outboard boats in use (5. 315 million)(4) yields  399 million boat hours
per year.  Assuming that an outboard boat always has a motor pushing  it
(sometimes 2 motors),  the boat usage method results in a higher motor
usage estimate than the  motor usage method does.  Since  so many ap-
proximations and assumptions are necessary for  this report, it is
deemed appropriate to choose the estimate which will result in the more
conservative impact estimate for outboards, namely that each motor is
used 50 hours per year.

       To be really rigorous in calculating impact, average power output
for engines  in each of the four power categories is needed.  These values
could be multiplied by the population fractions at  the bottom of Table  17
to determine a "power-weighted" population breakdown, but they cannot
be extracted from the available data.  The only alternative is to assume
a value for average horsepower in each power category, and check the
resulting average power output for all motors against the known average
value of 24. 6 hp.  Assuming values  of 5 hp, 15 hp,  35 hp, and 65 hp
for the four categories,  the resulting average power output  is 25. 8 hp
(close enough to the known value) and the weighting factors for the
categories become (in order of increasing power) 0. 0612, 0. 158,  0. 306,
and 0.475.  These factors are "full power" weighting factors, so to
derive a representation of the breakdown  of power generated in the
field, they must be multiplied by their respective load factors given at
the bottom of Table 11.  This process yields the factors 0.0261,  0.0722,
0. 112, and 0. 158 (designated Wk = (hp generated  by engines in category/
(total hp available) ) for the power categories in order of increasing
power,  and their sum (0. 368) is  the overall composite load  factor for
the entire motor population.

       The  power-based impact calculations now take the form

^ = (engine population) (avg. hp) (usage, ^11) (    * ^ -  )  (  £ WkBk)
yr                                       Yr  V. U£ fxiu-'g   k _ i


where the Bk are brake specific  emission factors for the four engines in
g/hp hr.

Filling in the constants, this formula becomes
                             4
            = 9.90x103  (  }_y  wkBk).

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                                                                   48

Note that the "full power" weighting factors are used only to determine
how much weight is given to brake specific emission factors for each
engine,  not to calculate impact directly,  which makes calculated impact
relatively insensitive to the accuracy of the assumed averages.

       To  calculate impact on a  fuel basis,  it is first necessary to com-
pute the fractions of total fuel used by engines in each category.  These
fractions can be calculated by

 Qk = (fraction of fuel)k  =    (fraction hp generated)k (BSFC)k
                                 (fraction hp generated)k(BSFC)k
                            k = 1         4
                             WkBSFCk/  V Wk
                                        k =  1
                             4                 4
                                 (W BSFCk/   y  Wk)
                                               / /
                            k = 1             k -  1

where BSFCk  brake specific fuel consumption (gal/hp hr) for each
category.  The fuel-based impact calculations now  assume the form
                                                       4

                                         1 ton        (  /     k k )
       I2E - (total fuel usage, gal/yr) (9>072xi05g)     ^


where the  Fk are the fuel specific emission factors for the four engines in
g/gal.  The four values for Qk (for the categories in order of increasing
power) are 0. 0888,  0.239.  0.293, and 0. 378.  The  latest widely-quoted
figure for fuel consumption by pleasure boats is 1.  1 billion (1. 1x109)
gallons for the year 197l(5).  This figure is intended to include fuel
used by inboard/outdrive units (255, 000) and gasoline-powered inboards
(730, 000 total inboards, no separate estimates for  diesel and gasoline)'15).
If it is assumed that the total inboards included the inboard/outdrives,
and that 75% of inboards used gasoline rather than  diesel fuel, it could
be estimated that about 550, 000 gasoline inboards were in use at the
end of 1971.   If it is  further assumed: that the inboard engines averaged
100 hp; that they were used 75 hours per year; that their average fuel
consumption was 0. 08 gal/hp hr;  and that their average composite load
factor was 0. 333; then it can be estimated that  gasoline inboards used
about 0. 11 billion gallons of fuel in 1971.  This  amount is  10% of the
total gasoline figure  given above, making the estimated total for out-
boards 0. 99x10^ gallons.  Although this estimate has been derived from
the only industry figure available, it is considered  to be unrealistically
high because the industry fuel consumption figure is likewise considered

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                                                                   49
high.  Calculations will be carried out on both annual usage and fuel bases
for comparison, but impact calculated on the fuel basis will not be as-
sumed reliable.

       Using the equations and statistics  given above, the national impact
of outboard motor emissions for 1971 has been computed on both brake
specific  and fuel specific bases.  The impact data are given in Table 18
for total emissions as well as those calculated to end up in the atmos-
phere and in the water using assumptions stated earlier.  As noted in
the title  of Table 18, the impact numbers are for 2-stroke water-cooled
engines only.  All inboard,  inboard/outdrive,  air-cooled outboard, and
4-stroke  outboard motors are excluded from the impact estimate, the
latter two categories being assumed to have negligible impact and the
former two being omitted because they are outside the intended scope
of this project.

    TABLE 18. NATIONAL IMPACT ESTIMATES FOR TWO-STROKE
       WATER-COOLED OUTBOARD MOTOR EMISSIONS, 1971
Contaminant

   HC
   CO
   C02
NOX as NO2
SOX as SO2
Contaminant

   HC
   CO
   CO2
NOX as NO2
SOX as SO2
Contaminant

   HC
   CO
   C02
NOX as NO2
SOX as SO2
                       Total Estimated Emissions,  10& tons per year
Brake Specific Basis
0.494
0.965
2. 38
0.0022
0.00106
*Estimated Atmospheric
Brake Specific Basis
0. 310
0. 917
1.41
0.0018
0. 00100
*Estimated Water Phase
Brake Specific Basis
0. 184
0. 0475
0.966
0.00039
0.000058
Fuel Specific Basis
0. 826
1.62
3.98
0. 00377
0. 00188
Emissions, 10 tons per year
Fuel Specific Basis
0. 520
1. 54
2.37
0.0031
0. 00178
Emissions, 10° tons per year
Fuel Specific Basis
0. 308
0.0796
1.62
0.00066
0.000102
*subject to qualifications given earlier.

-------
                                                                    50

      In the case of outboard motors, evaporative losses of fuel have not
been included in the impact estimates for several reasons.  Spillage and
evaporation losses during fueling and fuel/oil mixing may be significant,
but no data on these losses are available.  Evaporation from the car-
buretor during running is probably of less  significance,  but in any case
no data are available on this point either.  It stands to reason that "hot
soak" losses such as those from automobile probably do not occur,
since outboard carburetors do not sit directly on top of the engines and
are not subjected to strong heat input following engine shutdown.

      Evaporation from the fuel tank can occur if the tank vent does not
incorporate a one-way valve (preventing flow out of the tank) and if the
vent is left open.  The fraction of tanks fulfilling these  requirements for
evaporation is not known,  however, so tank losses cannot be estimated.
In summary, it is highly probable that some evaporation losses occur,
but information necessary to a quantitative assessment of these losses
is not available.

      The estimates of sulfur oxides (SOX) impact are based on a  fuel
sulfur content of 0. 043% by weighti1'*) and  the assumption that all the
sulfur which is oxidized at all is oxidized fully to SC>2°  It is also  assumed
that the fraction of sulfur being oxidized to SC>2 is the same as the frac-
tion of fuel being burned, a necessary assumption for 2-stroke engines,
and that the remainder is emitted as elemental sulfur (and not included
in the impact estimate).

      The determination of which set of impact numbers (brake specific
or fuel specific) is more accurate hinges on the accuracy of the major
assumptions  made about yearly usage and fuel consumption.  The
problem with fuel consumption data is that the data-gathering process
is prohibitively complicated,  so it must be assumed that published
numbers are no more than educated guesses.  The estimate used  for
annual usage is probably a guess also,  but it seems reasonable (it
can be dealt with in terms of personal experience,  whereas national fuel
consumption cannot) and it could be checked by a statistical survey much
more easily than fuel  consumption could be.  At this point, then,  the
emissions impact calculated on a brake specific basis is considered
more reliable, and will be used to compare to EPA Inventory Data.

      Another note on the applicability of the impact figures given in
Table 18 concerns the inclusion of older motors in a population charac-
terized by tests on new motors.  If the design of outboards had been  highly
evolutionary (at least  in those sub-systems which might influence emis-
sions drastically),  the age disparity would be a subject of concern.  Such
drastic changes have not occurred,  however,  so it is doubtful that emis-
sions from older engines are greatly different than those from newer
engines.

-------
                                                                    51

      It should also be noted that this study forms no basis for deter-
mining the fate of exhaust products which are estimated to be retained in
either the water phase or the atmosphere.  The organic constituents
scrubbed out by the water may stay there (soluble organics,  for instance),
or they may rise to the surface and evaporate.  Inorganic materials (CC>2
and NC>2) are probably dissolved and retained in the water, although no
sub-study was performed to prove it.  Likewise,  some constituents
which make their way to the atmosphere  may remain there, but others
could remain close to the surface of the water and dissolve or condense
later; the time factors which may be involved in these processes are
simply not known.

      A comparison of the impact estimates given in Table 18 to the most
recent EPA National Inventory Data^) is shown in Table 19.   The  in-
ventory data,  of course, are for air  pollutants only,  so the percentages
in the columns at right are for atmospheric  outboard emissions only.
Emissions of aldehydes were not calculated on a mass basis because
their overall impact would have been very low,  probably about the same
order of magnitude as NOX.   The concentration data  on aldehydes  should
be sufficient for characterization purposes.

TABLE 19. COMPARISON OF OUTBOARD NATIONAL IMPACT ESTIMATES
    WITH EPA NATIONWIDE AIR POLLUTANT INVENTORY DATA

                 EPA Inventory Data         Outboard Atmospheric
                 1970 106 tons/yr(9)	     Estimates as % of	
Contaminant  All Sources  Mobile Sources   All  Sources   Mobile  Sources
      HC         34.7          19.5            0.893         1.59
      CO        147.          111.             0.624         0.826
      NOX       22. 7          11.7            0.0079        0.015
                 33.9            1.0            0.0029        0.10
      Although not necessary to the requirements of the present contract,
it may be desirable at some point to estimate impact for outboards in
some area other than the whole U. S.  To this end, Table 20 has been
prepared to facilitate calculations.  It should be noted that factors ex-
pressed in each unit are rather heavily qualified, and that they are con-
sidered to progress from most accurate to least accurate in approxi-
mately the order shown.  In other words,  more facts  instead of assump-
tions should lead to more accurate impact calculations.

      In assessing impact,  importance is attached not only to the mass
emissions data, but also to the locales where and the  times when the
emissions are released.  For outboards, a large majority of emissions
undoubtedly occur in rural (rather than urban or suburban) areas, and
during non-working hours (probably weighted heavily  toward weekends).

-------
               TABLE 20.   COMPOSITE EMISSION FACTORS
              FOR USE IN SMALL-SCALE OUTBOARD MOTOR
             IMPACT ESTIMATES (SUBJECT TO QUALIFICATIONS)
                                                                            52
    Emission    Qualifi-   Medium
       Unit	  cations    Affected

    g/hp hr      1,2,3     Atmos.
                           Water
Exhaust Constituent
                           Total

    g/gal fuel    1,2       Atmos.
                           Water
                           Total

    g/motor hr   1,2,4     Atmos.
                           Water
                           Total

    kg/motor yr  1,2,4,5   Atmos.
                           Water
                           Total
HC
84.9
50.5
135.
503.
299.
802.
769.
457.
1,230.
38.4
22.9
61.3
CO
252.
13.0
265.
1,490.
76.9
1,570.
2,280.
118.
2,400.
114.
5. 88
120.
CO?
388.
265.
653.
2,300.
1,570.
3, 870.
3,510.
2,400.
5,910.
176.
120.
296.
NO*
0.50
0.092
0. 59
3.0
0. 54
3.5
4. 5
0. 83
5.3
0.230
0.042
0. 270
so*
0.49
0.027
0. 52
2.9
0. 16
3. 1
4.4
0. 25
4.6
0. 220
0.012
0.230
List of Qualifications:        1.  Based on Dec.  31,  1971 distribution of outboard
                               motors in the U.S. by size

                            2.  Based on experimental data generated under the
                               subject program only.

                            3.  Engine rated hp should be multiplied by applicable
                               load factor before using this unit.

                            4.  Based on 24. 6  rated hp per motor and average
                               load factor of 0. 368

                            5.  Based on 50 hr usage per year

            The emissions are also undoubtedly seasonal,  and the amounts
     emitted in each area will depend on the length of the boating season there
     as well as the concentration of boats.  To make a seasonal/regional
     analysis possible, the U. S.  will be divided into northern, central, and
     southern regions.  The  northern region is  roughly between 49° and 43° N.
     latitude, the central  region between 43°  and 37°, and the southern region
     between 37° and 31°.  States straddling the dividing lines will be placed

-------
                                                                        53
in the region containing the majority of their populations.  In addition,
the boating  season will be assumed as  6 months in the northern region,
7 months in the central region, and 8 months in the southern region.
An estimated distribution of outboard motors by state' ' is included as
Appendix E, and it has been used in conjunction with the assumptions
above to arrive at the breakdowns given in Table 21.  According to this
analysis, some 84%  of all outboard emissions occur in the mid-summer
months and 16% in the fall.  About 15% appear to occur in the northern
region, 47% in the central region, and 38% in the southern region.
These results can be combined with the overall impact data to  obtain
mass emissions by season and region if such an analysis is desired.
       TABLE 21. SUMMARY  OF REGIONAL AND SEASONAL
           VARIATION OF OUTBOARD MOTOR EMISSIONS

               Percentage of Annual Emissions by Season	   Regional
 Region     Dec. -Feb.   Mar. -May   Jun. -Aug.   Sep. -Nov.    Subtotals

Northern       0.00          7.28         7.28        0.00         14.6
Central        0.00          20.2         20.2         6.76         47.2
Southern       0.00          14.4         14.4         9. 58         38. 3

Seasonal
Subtotals       0.00	41. 9	41.9	16.3

Total                             100. 1

       A simplified analysis such as that just described has obvious
inaccuracies, but it is still useful in determining overall usage and emission
patterns. It is also interesting to note that well over half the outboards
in use (3, 902, 000) are concentrated in the ten states having the largest
motor populations.  Motor  concentrations seem to be highest in coastal
states and those bordering the Great Lakes, which is quite logical.  The
three west coast states account for 10.4% of all outboards,  three Gulf
coast states  (not including Mississippi and Alabama, which have only little
coastline) account for 15. 3%, and the eight states bordering the Great Lakes
account for 37. 6%.  Taking into account the 17. 1% of outboards in the.Atlaniic
coast states  (other than Florida and New York, already accounted for),  only
about 20% of outboards are in inland  states.  This is not to say that boats in
states bordering  large bodies of water are always operated offshore, because
these same states also have numerous inland lakes,  but the pattern of con-
centration around the  country's borders is interesting.

-------
                                                                       54
                           VI.   SUMMARY

       This report covers a study of exhaust emissions from outboard
motors,  and it is Part 2 of a planned seven-part final report on "Exhaust
Emissions from Uncontrolled Vehicles and Related Equipment Using
Internal Combustion Engines, " Contract No. EHS 70-108.  It includes
documentation and discussion on characterization of exhaust emissions
from four water-cooled 2-stroke outboard motors (sections III and IV),
and estimation of emission factors and national impact (section V).   The
testing was restricted to water-cooled 2-stroke engines because they
dominate the field (estimates  of the number of motors not in the  category
are 5% or less).  As a part of the final report on the  characterization phase
of EHS 70-108, this report does not include information on aircraft turbine
emissions,  outboard motor crankcase drainage (except for qualitative
mention), or locomotive emissions control technology.  As required by
the contract, these three latter areas have been or will be  reported on
separately.

       Emissions tests on the four outboard motors; an OMC (Johnson)  4 hp,
an OMC  (Johnson) 9. 5 hp,  a Chrysler 35 hp, and a Mercury 65 hp; were
conducted in the Emissions Research  Laboratory on stationary test stands,
with power absorption by eddy-current dynamometers connected to the
propeller shafts.  Emission concentrations were measured both before and
after the exhaust gases were bubbled through water to determine amounts
of exhaust  constituents which  remained in the water phase and which
bubbled through into the atmosphere (subject to restrictions of the laboratory
situation).   Special tests were conducted with one engine to evaluate the
effects of turbulence, bubble size, and waterrexhaust gas ratio on the
scrubbing of exhaust gases by the water.

       Exhaust constituents measured were total hydrocarbons by FIA;
NOX and NO by chemiluminescence;  hydrocarbons,  CO, CO2, and NO by
NDIR;  02  by  electrochemical analyzer;  aldehydes by wet chemistry;  and
light hydrocarbons by gas  chromatograph.  National impact was calculated
for hydrocarbons, CO, CO2,  and NOX for both the air and water phases.
Expressing the atmospheric emissions from outboards as percentages of
1970 national totals from all sources^  ,  outboard hydrocarbons amounted
to 0. 893%, outboard CO was 0. 624%,  NOX was 0.0079% and SOX was 0.0029%.
As percentages of mobile source emissions, outboard hydrocarbons were
1. 59%, outboard CO was 0. 826%, NOX 0.015%, and outboard SOX was 0. 10%.
Emissions of CO2, while not relatable to  available source inventories,  may
be of more interest from a water pollution standpoint than from an air
pollution standpoint.  Regarding  the regional aspects of pollution from out-
boards, it  is estimated that about 15% occurs in the northern third of the
country,  47% in the central third, and 38% in the southern third.  Estimates
of motor populations by state also show that about 80% of outboards are con-
centrated in states bordering  the oceans or the Great Lakes, but the fraction
of operating time spent offshore  as compared to that spent on inland waters
is not known.

-------
                                                                       55
       To make a more accurate assessment of outboard emissions,
additional testing including some newer types of engines would be re-
quired.  It would also be of interest to include a rotary outboard such
as those manufactured by Yanmar of Japan,  because it is likely  that
Wankels will soon find application in outboards.  Another refinement
could be added by conducting some sort of usage survey, perhaps with
simple hour meters connected to engines running in various places
around the country,  to make the utilization numbers more accurate for
various size  classes of motors.

       Although it was  not an objective of this project,  work should be
done to  define the mixing of exhaust gases and water in the real situation
more precisely.  This work might initially involve underwater photography
of a number of engine/propeller/hull/speed combinations to determine a
range of bubble sizes and residence times and some kind of a turbulence
index.  That  information could then serve as basis for design of a fluid
dynamic simulator which could be used for further studies.   An additional
study to determine characteristics of a number of lakes and rivers (tem-
perature,  pH,  etc. ) would serve to shed more light on the chemistry of
the mass transfer process.

-------
             LIST OF REFERENCES AND BIBLIOGRAPHY

 1.   Personal communication from M. Boerma of OMC to C. T. Hare
     dated January 17,  1972, regarding boat load and boat usage surveys
     conducted by OMC.

 2.   Federal Register, Volume 35, No. 219, November 10,  1970,  Part II,
     p. 17294.

 3.   Personal communication from M. Boerma of OMC to C. T. Hare
     dated September 8,  1972, regarding updating of boat usage survey
     information gathered by OMC.

 4.   Boating 1971 - A Statistical Report on America's Top Family Sport.
     Boating Industry Associations, 401 North Michigan Avenue, Chicago,
     Illinois 60611.

 5.   The Boating Business 1971.   The Boating Industry.

 6.   Recreational Boating Registration Statistics from USCG Report
     CG-357, distributed by National Association of Engine and Boat
     Manufacturers, May 1970.

 7.   R. A.  Walter,  et al, USCG Pollution Abatement Program: A
     Preliminary Study of Vessel and Boat Exhaust Emissions,  Report
     No. DOT-TSC-USCG-72-3, November 1971.

 8,   Oral presentation given to South  Texas Section of the Society of
     Automotive Engineers by Don Reed of the Boating Industry Associa-
     tions,  February 23, 1972.

 9.   1970 EPA Air Pollution Inventory Estimates, Annual Report of
     the Council on  Environmental Quality.

10.   Proceedings, Fifth National Conference on Access to Recreational
     Waters, September  17.-20, 1967, Boston, Massachusetts.

11.   Outboard Marine Corporation Examines Air and Water Pollution,
     S. L. Metcalf, Chief Engineer, Presented to EXHAUST EMISSION
     INSTITUTE,  University of Wisconsin,  October 19 and 20,  1967.

12.   Effect of Power Boat Fuel Exhaust on Florida Lakes, distributed
     by Marine Exhaust Research Council, prepared by Environmental
     Engineering, Inc. ,  2324 S.  W. 34th Street, Gainesville, Florida
     32601.

-------
                                                                        57
          LIST OF REFERENCES AND BIBLIOGRAPHY (Cont'd)

13.   Personal communication from Don Reed of the Boating Industry
     Associations to William Rogers Oliver of the Environmental
     Protection Agency,  August 8, 1972.

14.   Petroleum Products Survey No. 73,  U.  S. Department of the
     Interior,  Bureau of Mines,  January  1972.

-------
               APPENDIX A




EMISSIONS DATA ON A JOHNSON 4R71 ENGINE

-------
                                                                     A-2
JEST DATA  ON   ^OWNSOM   4*71   OUTfcOARD
           -  1/27/72                \\-2Bfc9-01

MODE
1
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-------
                                                       A-3
JEST DATA
  I/4/T2-
ON   JOHNSON
I /27/72
4R71  OUTBOARD MOTOR
      \\-26fc9-Ot

MODE
1
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5.07
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-------
                                        A-4
TEST  DATA   ON
   1/4/71-  1/27/72
4R.H   OUTE-OARD  MOTOR
        \\-28fc9-OI

MODE
1
1 A
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3
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-------
                                    A-5
JEST  DATA  ON
   1/4/11-  1/27/72
4R~M   OUTBOARD  MOTOR.
        \\-Z6fc9-OI

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£.7
5,4
6.9
5.9
7.4
AVERA&E
OR TYP1C.AL
VALUE.
•r,.\
7.3
5.9

-------
                                                                       A-6
JEST DATA  ON   -iOWNSON  4R7.1   OUTBOARD  MOTOR
   I/4-/12.-  1/27/72                 \\-28fc9-OI

MODEL
1
1 A
2
2 A
3
3 A
4
4/\
£
5A
6
6 A
FOEL COMSOMPTtO/V) , 'b~/Vxv (.MORTAL AMD "A" MODES)
RUN NUMBER
5
























£
























7
























e>
4.1 I

2.7(.

4.") 4

I.ZS

v.OO

0.^0

9
4. 04

i.80

1-87

». \?

I- 01

0.97

* \o
3.34-

2.t>^

\- BZ

1. I (o

0.93

0-9&

* \l
5.4Z

2.5&

2.0^-

\. 29

1.05

0.9&

AVERAGE.
OR TYPICAL
VALUE.
4-08/*3.3,6

2'^/2.(oO

1,92

I. 2.2.

1. 0)

0.9G

     * NEiAj  FULL  PUMP INSTALLED   PR.\OR- TO   E.OKJ  >0

MODE
1
1 A
2
2 A
3
3 A
4
4 A
£
S A
6
*A* MODES)
RUN NUM&EK
s
























6
























7
























8
IBID

12,50

88O

5(b7

4-S4

4-08

9
IB 30

12.70

848

539

4-BS

440

* 10
15ZO

M60

&2.S

52- G

422.

445

* n
isso

mo

92S

585

47fe

445

AVERAC-E
OR TYP1C.AL
VALUE.
IB50As30

lifc°An«)

B70

553

458

4S5


-------
               APPENDIX B




EMISSIONS DATA ON A JOHNSON 9R72 ENGINE.

-------
TEST  DATA  ON  JOHNS.ON
                           B-2
K\> OUTBOARD  MOTOR.

MODE
I
IA
I
2.A
3
3A
4
4- A
5
5A
*>•* c. x\0"4 (uoET)

1
3.3)0
2,fcfc
2.84
1,52
3.4ft
1,91
fc.Bl
3.49
9.78
5.33
10.22
5.42
RUN NOMBER
2.
3.42
2.0ft
4-04
2.12
S.S(o
2.8&
-?.I2
3.44
8.4
4.48
9.3k
4M
3
3.4k
2.1fc
4.04
2.2.8
4-90
2.&0
5.1Z
3.20
6.0ft
3.44
l.Gfc
4.lfc
4-
3.30
2.08
3, (08
2.20
4.fc4
2.86
5.12
2.92
S.lt.
2.80
fc.Sfc
3.-7G
5
3.54
2.4ft
4.04
2.52
£.\2
3>3fc
5.H
3.^C x iQ'4 (IJOET)"
RON NOMBER
I
Z.3G>
3-01
2-. 81
3.21
3.00
4.03
4-
1.30
1-12
1-90
\.8S
2.
-------
                                                            B-3
TEST  DATA  ON  JOHNSON  <}.£  H\>  OUTBOARD  MOTOR.

MODE
1
1 A
2
1A
3
3A
4
4- A
5
5A
fc
fcA
ND\R CO, VOLUME- % CUJET)

1
4.iG
4.83
3.G
4.50
3-4 \
7
5.25
(b.2.7
4-99
4-(b4
3.24
4.04
3.0&
7
7.72
5-71
7-94
5.4J
7.18
5-Ofe
G.77
5.0
-------
                                                            B-4
TEST  DAT/\  ON  JOHNSON  9.5  Kip  OUTBOARD  MOTOR.

MODE
1
I A
2
1A
3
3 A
4-
4-A
5
5A
l»w (WET)
RUN NOMBER.
I
8l
4-0
39
13
10
14
12.
2.
IS
IG
55
5G
32
3^
19
15
5-9
3.G
fc,2
4.3
3
7B
85
52
5G
3.0
30
\1
It
5.)
4.6
5.3
4.B
4-
95
104
58
55
39
34-
»9
»9
G.4
(c.7
(b.(o
5,3
5
80
91
57
5d
34
33
»9
n
3.5
»-9
3.5
2.9
MLVJE
80
&(o
53
5G
33
31
11
O
6,7
5-0
6.9
5,4-

MODE
1
1 A
1
2A
3
3A
4-
4A
5
SA
fc
bA
CHEM\LUM»N)ESCENJT M'o, y>^^ (IU^T)
RUN NUMBER
»
80
73
4B
5£
2.7
3»
£8
31
7.0
5.8
9.0
fc-7
2
75
78
42
4ft
24
24
l?>
12.
3.9
24
3,1
2-9
3
G>9
61
41
53
X7
2G
\5
15
35
z.9
4.2
1.5
4-
61
99
49
53
28
31
1G
IG
4.8
4.8
4,4
3.8
5
12
B2
52.
53
2.&
31
15
IG
2.0
!•>
2.G
»•>

7G
48
52
Z7
2J
14
»S
4,2
z.9
s.l
S.B
A\JER./\^E
OK. TYPICAL
VALUE
13
80
47
53
27
29
1&
n
4.2
3.4
4.9
3.G

-------
                                                                 B-5
TEST  DATA  ON   JOt\NS,ON    OUTBOARD MOTOR.

MODE
I
IA
2.
2.A
3
3A
4-
4-A
5
5A
fc
fcA
ND1R NO, »A* OJOET)
RUN NUMBER
1
lit
94
110
101
95
94
8G
&o
4Z
S3
7)
fcO
2.
90
\01
-75
60
"19
80
19
80
Ifc
OO
\0fc
87
87
11
15
Q>5
ET)
RUN NUMBER
\
3.t
4.

.S G.& ">.l 7.S 8.3 2. 3.B 4,4 4.3 4-9 £.5 (o.l 5.S 5.0 7.0 1.& 8.0 9.3 3 3.& 4.Z 3-1 4-9 4-6 5.8 5.2. 5-4 (o.O G.9 fc.7 1.8 4- 3.5 4-3 4-3 5.3 5.3 &.3 5.5 Q-8 (o.O Q>. 8 fc-8 7.8 5 3.t 4.G 4.0 5.1 5.0 fe.O 5.S G.4 7.4 8.4 8.4 9.5 4,3 5.3 5.3 5.8 5.S .3 Q>.7 7-t 7-7 6.7


-------
                                                              B-6
TEST  DATA  ON  JOKNS.ON    OUTBOARD  MOTOR

MODE
1
I A
i
2LA
3
3A
4-
4-A
5
5A
6
7
3.94
4,07
1-99
1.93
1,59
l.fci
4-
&.09
6,\4
7.09
7.05
5.9 1
6.90
3.&0
3.73
I. GO
\,55
I.S(p
1.52.
5
7.&I
-7.BG
7.2.Z
7.2.Z
5.B8
5.&G
3.74
3.t4
2,2.1
2..3Z
1. 70)
1-7 \
(b
8.08
B,»7
7.35
7-^0
G..1&
&. 19
4.09
4.07
Z.2.S
2.2.0
\.7S
».77
7
7,95
8.00
7.3G
7.2.B
(b.2.7
G.30
4.\&
4-J3
2.00
2.01
l.fts
\-B4-
8
8.37
ft.37
7.3»
7.38
s.%
5.97
3.74
3.73
2.1 1
2.|0
I.&B
I.BG
A>JERAe-E
OR TOPICAL
VALOE.
8,n
8,14
7.35
1.35
6.05

3A
4-
4A
5
SA
ft
feA
FUEL CONSUMPTION) , V**
RUN NOM BER.
1
3710
3GGO
3370
3370
2&00
2810
^850
i860
990
990
700
3G30
3340
3350
ZB50
2-860
1900
1870
9 )0
9)4
82,9
834
8
3800
3800
3320
3350
2.100
2110
noo
1&90
9G.O
95S
8SS
84S
AMERAG-E
OR. TYPICAL
VALUE
3&&0
3700
3330
333.O
^770
2180
1800
1790
925
924
790
193

-------
                 APPENDIX C




EMISSIONS DATA ON A CHRYSLER 356HA ENGINE

-------
                     C-2
TEST  DATA,  ON  CHRYSLER  35
OUTBOARD   MOTOR.

MODE
1
IA
2
2A
3
3A
4
4A
5
5A
fc
fcA
FIA HYDROCAR&OiOS, |>|>m C x. \0~* (.WET)

1
4. OB
2.40
3.B8
2.5(b
4-fcZ
3.04
5.2&
3.1 (b
7.12.
4.9Q>
10.12
7.»2
RUN NOMBEP.
£
4.00
3.04
3.7G,
2-72.
3.(b4
2.48
3.12.
2.40
5.\1
3.44
7.44
4-4&
3
3.44
2.40
3.40
2.. l&
4.4^
2,9fc
5.2.Z
3. 48
1.9fc
5.4>0
»0. 9G
6.9Z
4-
4..fcZ
2.52
4.0ft
3.04
s.fco
3.74-
6. Q>4
5.92.




7




5.K C. x \0"4 ^WET)
RUN NUM&ER
»
1.85
».49
\.94
2.14
1.48
2.02
1-82
2.0
1.80
1.88
t.93
2.23
1.92.
1.88
2.4-1
2.fcO
4.8 \
5.(o7
fc.22
7.2>\
4-
2.0fc
2.50
1.88
Z.23
2.35
2.94
2.55
3.20
4.89
5-0)7
5.
-------
TEST  DATA*  ON  CHRYSLER.  2£
                     C-3
OUTBOARD   MOTOR

MODE
!
IA
2.
2A
3
3A
4
4A
5
5A
fe
&A
ND1R. CO, NJOLOME- % (.WET)

1
.3.OQ>
7.XO
5,08
5.16
5.16
S.fct
4- 1C.
5.2.1
RUN NOM&ER
£
1.38
&«34
5.B9
(b.feft
S.3&

5.05
5.47
4-
7.16
8.33
fc.91
7.15
fe.57
7.4t
(b.2L4
(b.84-
S.fot
fc.2.0
4-94
S.Z7
S
fe.7\
7.5S
(».17
l.bS
((,.&,&
1-41
.92
1.83
(b.2.0
l.OZ
Q>.\7
1.04
5,74
fo.35
S.Sfc
5.84
4.90
5-2,0
.17
4.\7
(b.£2
4-70
.48
4.54
5.<)9
4,20
5.43
3,.
-------
TEST DATA,  ON  CHRYSLER   35 KJ>  OUTBOARD
                                                          C-4

MODE
1
IA
2.
1A
3
3A
4-
4A
5
5A
€>
feA
CHEM»LUMlNtSCENT NO*, ^~ O>ET)

1
52.
50
SO
48
3
4,8
3
4Q,
41
46
43
3fc
2.7
^7
17
18
S.3,
»3
5.8
4
35
2fc
39
2.9
32
2.0
i2
Vi
l(b
2.5
\5
1-9
5
48
40
43
35
33
»9
1G
\

B O 10 id 3.0 ANERAG-E OR TYPICAL VALUE 1-5 44 59 40. 4-0 33 11 2

|7 41 18 34 19 2.2 9 l& 3.4 J^ODE 1 IA 1 1A 3 3A 4 4A 5 5A e> &A CHEMILOMI NESC EAJT NO, |p|»^ C^OtT)' RUN NUMBER \ 43 4G 40 43 2.Z <9 19 18 5,0, 4.8 »7 \5 n 2.C, M 3.5 \.2. 5 2>t 37 30 33 >8 O 15 15 5,3 3.9 fc.l 4-3 G 2-4 2-1 Ib l& 10 8.G 5.3 3.9 1 17 18 18 \7 10 9.0 5.0 3-0 WER.AG-E OR TYPICAL V/VLOE. I-S 35 35 35 3fc 10 19 »7 17 4.8 3-9 5,2. 3.G 6H — it 2.4 17 l& 10 8.8 5.) 3,5


-------
TEST DATA,  ON  CHRYSLER
                          C-5
\>\>  OUTBOARD   MOTOR

MODE
1
IA
^
2A
3
3A
4
4A
5
5A
fc
feA
ND1R NO, »>»>•* UOET)

1
50
4C,
4-7
53
51
40
3
G>7
70
Col
98
BO
3
53
foO
61
-73
90
BO
72
13
73
67
60
73
4-
    B (b7 71 73 GO GO 70 73 80 BO 6 89 94 80 &0 92 BO 102. 80 7 71 0.7 &3 73 77 73 8G G>7 ANERftG-t OR TVPICAL VALUE 1-5 65 0.8 73 73 78 75 W 64- Cb7 G>1 80 72 .G 3.5 4,4 4-B 5-8 G.9 7-B 7 a.9 3.7 3.4 4.2. 4.B S.Q> fc.9 fe.O /VMER.AG-& OR TYPICAL VALOE 1-5 -bA 4.3 3.1 4.0 3.8 4.6 4.1 5.0 5.1 5-7 G.O (0.8 GO 3.0 3.G 3-4 4.3 4,8> 5,7 Q..9 7.9

-------
                     C-6
TEST  DATA,   ON  CHRYSLER
OUTBOARD   MOTOR

MODE
1
IA.
2
2A
3
3A
4
4A
5
5A
€>
6A
FUEL CONSUMPTION), V^~/W

\
ZG.O
2S.8
IG>.9
n.o
U.4
U.3
1.2G
7.44
3.1J
3.B9
4,17
4.14
RUN NOMBEP.
2.
27.0
2C,B
l(D.B
n.o
12.3
11.2.
1.18
1.32.
3.71
3.\i




11.2
11.4
11.3
11-3
l.Bt
I.b8
4.44
4.5!


	

*IODE
1
U
1
1A
3
3A
4
4A
5
5A
6
GA
FUEL. eONSUMPT\ON, %/Vw^
RUN NUMBER.
\
H,800
\ 1,100
7G(oO
1100
5G4O
5S80
32-90
3360
112.0
1770
IB90
»920
Z
1 2,ZOO
12,200
It 10
1100
5510
5S10
3300
3320
I(b80
lG>40
I7»0
1&2.0
3
\\,600
11,500
1590
1G>40
53GO
5410
3570
3590
I9b0
1970
2Z40
Z13O
4-
n,ioo
UX700
&\10
8 HO
5750
5790
2>felO
350
5
U,400
l\,300
TblO
1930
500
3590
1930
1890
2080
2080
G




1820
1900
5520
54&0
3510
3590
2060
2050




1




1800
l&SO
SfclO
5
-------
                APPENDIX D




EMISSIONS DATA ON A MERCURY 650 ENGINE

-------
                                                              D-2
TEST  DATA  ON  MERCURY  .52
5.O4
7.22
5. 52
4-
4--GB
3.04
4.00
2.56
3,53
2.28
5.16
3.^1
6.00
4.64
7. 22
5.84
8.04
7. 2O
5
4.8G
3. 12
4.44
4.44
3.74
2.5(6
4.8G
3.80
5.88
4.64
6.96
s.66
7.9G
G.&O
6
4-68
3.40
4.00
2.80
3.74
2.56
4-4G,
2.32
5,ft&
4.G4
6.94
5. 6O
ft. 08
KCMO"4 (lAJET)
RUN NUMBER
2
2.64
2.8 I
2. SO
2.45
2. 14
2. 15
3.15
2.50

- - --


	


	

3
3.2. 1
3,77
3.04
3.24-
2,41
2,G£"
3.01
3.17
4.B9
s7\5

	

	

4




	











. _ . .. _








s



























G
3.35
2.(bO
3.14
3. 17
1-68
1.89
3. 14
3.45
4.41
4,77
5.63
5,91




AOJERA&E
OR TVPtCAL
VALUE
3.07
3.0G
2.81)
Z.9S
Z.I4-
2.23
3. 1O
3.24
4-65
4.9G
5.63
5.3 1 	





-------
                                                             D-3
TEST  DATA  ON  MERCURV
   Z/2-1/T2. -
OUTBOARD   MOTOR

MODE
I
1 A
2
I A
3
5 A
4-
4A
£"
5 A

3.58
2.78
G
3.IO
3.4-8
2.12
3.0G
3.34
3. &3
4.
7. 14
4.17
7.82
G.32.
7.92
5.04
6.44
4.90
5.&4
4-78
4- l
-------
                                                              D-4
TEST  DATA  ON  MERCURY  fc£0   OUTBOARD   MOTOR
            - 2/2.8 7-72.                     H

MODE.
1
I A
1
1A
3
5 A
4
4-A
5"
S A
 A
7
1 A
CHEHIUUM INESCLEIOT NO, . \>P~ (WET1}

2
186
186
113
12O
11
88
12
il
0>
4
7
3
(o
4
RUN NIUHBER.
3
156
»55
320
21
\ ai
\l(o
10
G>9
IG
10
G
5
G
4-

e>
5
&
4
7
4
AVERAGE
OR TYPltAL
VALUE
113
I&G
222
2.10
19
8(0
n
1(0
7A
5,0
1,4
i-8
6.C,
4.4-

MODE
1
1 A
2
Z A
3
3 A
4-
4 ^
5
5 A
G
6 A
7
7 A
C HEMILU MlfOtSCEMT NO, Up"" CujET)
RUN NVJMS&R
2
170
181
zoi
215
6&
1&
8
8
2
2
4
2
3
2
3
138
138
231
2 £5
98
101
\
17
4
2.
4
3
5
3
G
»7G
142
I 98
Z25

-------
TEST  DATA  ON  MERCURY orr>  ~.
                                                             D-5

MODE.
1
\ A
2
1A
3
3 A
4
4A
S
5 A
G
6 A
7
1 A
NIMK NO, H"« (.UJET)
RUN NUMBER.
2
14-2
\55
1&3
H9
75
76
41
23
28
IS
4-G,
38
51
53
3
130
12)1
174
139
80
16
38
4
-------

MODE.
1
1 A
1
Z A
3
3 A
4
4 A
£
5 A
6
G A
7
1 A
FUEL CONSUMPT\OM , lb«A*
RUN NUMBER.
2
4O
47-4
3fc.9
3fc.£
24.7
24-9
a. 4
lt.4
12.0
12.0
10.4
\0,G
7.14
7.0<)
3
46,9
47,1
37.5
2>7.2
24.4
24.4
\7.3
17.5
12.2
12.5
10.3
\o-4
fc.89
7.0(o
4-
4-5.7
4\»ERAGE
OR TYPICAL
VA.LUE
44,1
4-(o.8
2>1,3
37.2
2.4.7
24-7
11.0
n.2
*2.0
\2.0
\0.t
lO.fc
l.fcl
7.51

MODE
1
1 A
2
Z A
3
3 A
4-
4 A
5
5 A
G
6 A
7
7 A
FUEL. CONSUMPTION , V>\*
RUN NUMBER
2
Z\,300
2^1,500
lib/700
Kb/ 70
472,0
31 2,0
5200
4
2.0,700
iO/900
n,ioo
n/300
n, too
n, 100
76>ZO
7fo2-0
53SO
S490
4720
4710
3\90
3090
5
2.1,000
2.\, 100
Kb/BOO
Ko,«)00
l\,300
\\.300
&070
&<2.0
54^0
5350
4-85O
4&5O
4030
3880
G
210,300
2.\,2.0O
I (o,9 00
\(o,BOO
\l,2,00
\\,300
~7fo70
7BSO
5350
52>\0
4^90
5030
3G70
3Q>40
ANERA&E
OR TYP\CAL
VAtOE
20,900
Z\,260
l
-------
                                                               D-7
SPECIAL TtS»T  DATA  ON  MERCORy  fcSO OUTBOARD  MOTOR

MODE
1
I *
1 6
i
3 A
3 &
5
5 A
5 B>
2 	
1 *
1 &
FIA HYDROCARE>OK)SX H>m C K icf4" (UJET)

1
5,19
4-20
4.00
3,83
2,fc5
2.48
(b.20
5.04
4.62.
9.53
8.20
8.00

2
5,27
3.92
3,70
3.75
2,45
2,4-1

5,20
4.80
10-00
8-40
8.40

3
5.2.9
2), 14
3.12.
3-91
2-4fc
2.37
6,83
5.00,
4.fc&
9,17
7,30
7.25
TESTT NUMBER
4-
5.0&
3.30
3,20
3.GG
2,52
2,28
4-
S.Sfc
3>73
2,52.
2.43
6,59
4.90
4,76
8,90
fo.95
fc,90

MODE
1
J_ A_
1 &
3
3 A
3 &
5
5 A
5 &
7
1 A
7 B
NDIR HV DROCARBON3SX |>HC x^0~4 (UJET)
TEST NUMBER
1
























2.
2,
2.55
2.48
4.48
5.02
4,90
7. 18
7. 5fc
^7,55
5
3,23
3.SG
3.73
2.25
2.7G
2.65
4-0,3
5,52
5.(b7
8.44
a 85
9.H
<0
3,21
3.69
3.49
2.Z8
2. 0,8
2.(b5
4.72
4- 97
5.09
7-7 1
8,09
8.23
7
4-90
5.31
5,13
3.52
2>.H
3,99












&
3,43
3,&\
3.77
2.45
2.9fc
1.84
3.98
4.42
4.54
7.9 \
8,41
8.69
9
2.9G
3,39
3,25
2.12
2.50
2,45
3.4G
3.80
4,3ft
5-4S
5,91
G.07

-------
SPECIAL TtST DATA ON  MtRCURy  fcSO  OUTBOARD
                                                        D-8

MODE.
1
1 *
1 6
3
3 A
3 B
5
S *
5 B
1
1 A
1 B
NblR CO , VOLUME. % (WET)

1
21.99
3.34
3.32.
3,4-3
3.10
3.9G
4.33
4,&e>
4,82
3.1Q>
3,91
5.89

2.
3.01
3.3.4-
3. 52,
3.11
3.50
3.40
4.22.
4.10
4-10
3,14
3.83
3.82
TEVT NUMBER.
3
3.\5
3.54
3.58
3,42.
3.98
3.1G
4-30,
4-13
4. 10
3.78
3.92.
3.8^
4-
2,99
3.25
3.34
3.28
3.5G
3.6)8
4.21
4.G4
4-G4
3,64
3,81
3.13
5
3.18
3.50
3.51
3.51
3.<)3
3.4,8
4.33
4.-J&
4,84-
3.91
4.04
4. 12.
G
3.23
5,41
3,4&
3.09
3.25
3.58
4-15
4.53
4-56
3.T7
3.98
3.9(b
1
3. »5
3,5)
3,5G
3,2.9
3,(o&
3.85
4.34
4.1C,
4.&\
3,11
3,50
3,01
B
3.19
3,29
3.St
3.24
3.foO
3. GO
4.38
4-81
4. 81
3,59
3.18
3.82.
9
3.25
3,
(b.SG
5,12
S,59
G,ft3
fe.04
5,93
4,10
4.13
5.30
2.81
2.5|
2.
1. G&
S.40
4.90
8,57
5.8G
5-32.
6.00
4.Q>9
3.11
3.33
2.G5
2.34
3
7,41
3.G8
3^0
8.04
5.04
4,\3
5-88
3,84
3,06
3.4\
2.07
1,86
4-
1.21
3.94
3.90
1.B9
3.97
3.71
5,30
3,2,2.
2.89
2,97
US9
n|-71
S
7.35
5.G4
4,fe4
ft,04
G.\7
5,14
5.G7
4-90
3.8G
3.31
2.1^,
2.52.
6
1.38
6.15
(b.OO
8.22
7.31
6, S|
5.11
5,12
4.13
3.31
3.09
2.14
7
7,72
1,4G
6.G>3
&.S9
8.33
7,31

-------
                                                        D-9
SPECIAL TtST DATA ON  MERCURy  fcSO  OUTBOARD  MOTOR

MODE
1
1 /\
1 6
1
3 A
2> &
5
5 A
6 £>
7
7 A
7 B
CHEMtLUMl DESCENT NO*, *>*>»* (WET)

1
254
248
2.4-0
91
99
92
1
3
4
6
2
2
TES.T MUnBEfc
2
2.|
6
2
2
(3
1
1
3
204
194
194
10
68
10
£
4
2
6
2
2
4-
2.2- 1
2-35
2»8
8G>
86
19
6
2
2
G
2
2.
S
m
208
1\8
12
82
80
1
3
4

2.
-?
I4G
151
I5G
12
80
13>
 1
150
147
65
12

-------
                                                           D-10
SPECIAL TEST  DATA ON  MERCURY fcSO  OUTBOARD  MOTOR


MODE
1
1 *
1 6
3
3 A
2> B
5
S A
.5 B
7
7 A
1 B
NDIR

1
ICbl
118
183
18
84
1G,
35
26
26
10
61
61
NO, t>t>"

2
139
l(b 2.
154
62
65
64
30
26
26
G>0
4G
46
" (.UJET)

3
l
4-
168
179
158
76
80
12
47
34
38
68
53
£3

T Nune
5
150
170
»55
64
64
57
30
2Q,
26
59
46
50

Efc
6
\45
141
141
71
16
G4
33
2.6
26
64
53
54


-)
134
140
ISO
80
84
84
50
46
46
12
12
16


e>
1 1 9
121
\2_8
80
88
84
42
34
38
11
12
12


9
126
120
I 16
81
84
80
39
2>4
2,8
6X
SO
53

'MODE
1
1 A
1 &
3
3 A
3 &
S
5 A
5 &
7
7 A
7 B
POLARO&R APH\C Oix VOLUME °/0 CWET)
TEST NUMBER
1
5.0
5.8
5.8
3,8
4,4
4,5
6.2
7.0
7.0
9,7
10.4
10-4
2.
£.3
6-2
6.1
3.8
4-8
4-7
6,2
1,1
7,1
9.9
10,4
10.4
3
5.4
6.4
<&.4
4. \
4.9
5.0
6.1
7.7
7.8
10.5
P. 2>
M.4
4-
5.2
6.2
6.0
4.0
4,9
4-9
G.3
1.2
7.2
9-7
\0. 3
10.3
S
5.4
6,3
6.2
4.0
4.8
4.8
6.5
7.4
7.4
\0,0
11. 0
M.4
6
5.3
5,8
6.2
4.2
i 4.9
^4.9
6.7
7-4
7.4
\0,1
10.8
10.8
7
5.3
£,4
5-4
3.G
4.0
4,0
5,4
6,2
6.2
8.5
9-2
9-2
B
5.2
6. 1
6.0
4.2
4-9
4-8
6.3
7.3
7.2
^.6
l\-3
|l\.4
9
5.3
6.4
6.2
4.2
5.2
5.2
6.5
7.4
7.6
9.8
\o.&
r\o,7

-------
                APPENDIX E

     ESTIMATED STATE AND  REGIONAL,
DISTRIBUTION OF OUTBOARD MOTORS, 1971

-------
                                                                     E-2
                ESTIMATED STATE AND REGIONAL,
           DISTRIBUTION OF OUTBOARD MOTORS, 1971(4)
Estimated Motors in Use as of
                                           31   1971
Northern Region
State
Idaho
Maine
Minnesota
Montana
New Hampshire
North Dakota
Oregon
South Dakota
Vermont
Washington
Wisconsin
Wyoming











Motors
38,000
86,000
333,000
25,000
44, 000
25,000
122,000
26,000
23,000
209,000
322,000
8,000











Central Region
State
Colorado
Connecticut
Delaware
Dist. of Columbia
Illinois
Indiana
Iowa
Kansas
Kentucky
Maryland
Massachusetts
Michigan
Missouri
Nebraska
Nevada
New Jersey
New York
Ohio
P ennsylvania
Rhode Island
Utah
Virginia
West Virginia
Motors
35,000
102,000
20,000
31,000
322, 000
186,000
102,000
72,000
85,000
130,000
192,000
478,000
201,000
42,000
15, 000
200,000
593,000
310,000
200,000
34,000
32, 000
124,000
26,000
Southern Region
State
Alabama
Arizona
Arkansas
California
Florida
Georgia
Louisiana
Mississippi
New Mexico
North Carolina
Oklahoma
South Carolina
Tennessee
Texas









Motors
132,000
40,000
101,000
430,000
440, 000
133,000
226,000
61,000
18,000
118,000
108,000
108,000
144,000
448,000









Sub-total
           1,261,000   Sub-total
3,532,000   Sub-total
2,507,000
                    All-Region Total - 7,300,000

-------