Kohler L600 User manual

KOHLER
GENERATORS
ENGINE
SERVICE
MANUAL -
.
SECTION
E-7
MODELS: ‘L600, 1654
.
CONTENTS’
SUBJECT SECTION-PAGE! SUBJECT - SECTION-PAGE
GENERAL
LU6RICAlION
Prestart Check List . 1.3
Gen.Specifications . 7.4
Service Schedule . . . . 1.4
Oil Requirements . . . . 2.1
Oil Pressure . . . . . . . . 2.1
i COOLING
I
I
I
Radiator Systems ... 6.1
Anti-Freeze ..... ... 6.1
Fan Belts . . . . . . . . . . 6.2
. . . . . 6.3
Marine Cooling
Oil Filler Cap ...... 2.1
Oil Filters 1 GOVERNOR Governor Adjustments 7. I
......... 2.2 -
Dry Air Cleaner ..... 3.1 ...... 8.1
Oil Bath Cleaner .... 3.2 1 GENERALSERVICES Cylinder Head Valves .............
Flame Arrestor I 8.1
...... 3.2 I Compressi on ........ 8.2
AIR INTAKE
FUEL Gasoline Carburetors 4.1 t
Fuel Pump . . . . . . . . . . . 4.4
, Automatic Chokes . . .. 4.5 1 RECONDITIONING Inspection-Analysis 9.1
Gas Carburetors 4.6 I Disassembly . . . . . . . . 9.3
. . . . .
Gas Regu1ators . . . . . . 4.7 I Reconditioning . . . . . 9.6
. Re-assembly . . . . . . . . 9.11
~~~ ~~ .
IGNITION Spark Plugs ....... .. 5.1
Magneto Sewi ce . . . . . 5.2
Magneto Installation 5.3
Ignition Timing . . . . . 5.4
I
I
1 SPECIFICATIONS Clearances-Fi ts .... 70.1
I . Ignition Specs. .... 10.2
t Torque Specs. .....* 10.2
KOHLER CO. KOHLER, WISCONSIN 53044

7 QUARTCAPACITY
(APPROX.)RADIATGR /--PRESSURECAP
THERMOSTATHOUSING
-FAN-BELT
-AUTOMATIC CHOKE
.
I
. . . .
/
/
f
f 1
IrDJUSTABLE4
~LLEY(BELT
YENSION)
FANBEFT-
FUELPUMP GENERATOR
END COVER
OILDRAIN- OILLEVEL
\ LAIR CLEANER
DIPSTICK (OILBATH TYPE) ,
FIGURE1-7
-M CARBURETORSIDEVIEW- TYPICALRADIATORCOOLEDPLANTWITHL600ENGINE
OILFILLER- MAGNETO WATERPUMl
3-7 7.5QUARTCAPACITY
#I______. -1--a-a-
BREATHERCAP-----r (STANDARD)c-i I (AWKOX. ] RAPIATOR~-/
/
CONTROLLER \ \
VIBRQMOUNT
.
COOLANT
-DRAIN
OIL FILTER
(OPTION)PAD
FIGURE1-2
--MAGNETOSIDEVIEW- TYPICAL RADIATORCOOLEDPLANTWITHL654ENGINE
12 . a
.

. PRESTART CHECKLIST
Lubricating Oil: Check crankcase oil level on dipstick- fill as needed to bring level up to Full mark.
Refer to Page 2. 1 for oil specifications.
Cooling System: On closed type cooling systems, remove radiator cap or cap on water cooled exhaust
manifold, then add clean fresh water until level is just below overflow tube. 7 to 7-l/2 quarts are
required for initial fill on radiator models, 5 to 57 f/2 quarts for heat exchanger models. If freezing
temperatures are anticipated, add antifreeze to radiator cooled and heat exchanger models. On direct
water cooled models, make sure cooling system is properly installed to insure sufficient coolant.
Direct systems are of the open type and cannot therefore be protected with antifreeze.
Air Cleaner: If oil bath type used,
bowl. Use same weight and grade
no prestart service except to make
unfas
of oil
sure
CARBURETOR ..-.w..v..ww
ten bowl retaining clamp and add oil to level marking (bead) in
as used in engine. Dry type and flame arrestor units require
elements are in place so that unfiltered air cannot enter engine.
FIGURE1-3-- CARBURETORSIDEVIEW- TYPICALRADIATORCOOLEDPLANTWITHL654ENGINE
connect lines
g-Z g$iF@%&%ZE~Z~ gasoline. from storage tank to the fuel pump. Fill tank
Use priming lever on fuel pump to prime system
before initial start up. On gas fueled plants, make sure system is properly hooked up before starting.
Refer to Fuel Section for typical arrangement and preliminary adjustments.
Battery: These elect&c plants feature exciter cranking which offers higher cranking speeds for
more positive starting. When battery current is applied to the generator, it functions as a motor and
cranks the engine during starting then is autotitically switched back to its generating function after the
e’ngine starts.
A 24 volt battery is required for DC generator models and a 12 volt battery for AC generator
models. 32 volt cranking is available for marine models. Connect the positive (t) terminal of the bat-
tery to the P terminal of controller and the negative (-) battery terminal to the N terminal on controller.
(Stamped on base of controller near starting solenoid or C coil. )
‘ITo start three-wire automatic start plants, it will be necessary to center tap the 120volt battery
or use two 67volt batteries to create a difference in voltage between leads Ll and L2. Without this,
both leads have to be connected to the battery positive (t) terminal, and cranking relays in L2 will not
operate when the voltage is the same. With the center tap, lead Ll is connected to battery + terminal,
L3 to the center tap and L2 to ground which is battery negative (0).
13
l

SERVICE
Kohler Model L600 and t654 engines are covered in this Service Manual.
4-stroke cycle’ gas or gasoline fueled engines. Both are liquid cooled,
out the manual. Differences are called out whenever significant through- Some of the general specifications are listed below for convenience--refer to the
appropriate section for more specific details.
SPECIFICATION I L600 I L654
BOREX STROKE
.*~**********o****o***................
DISPLACEMENT(CUBICINCH)
l o.**.*.**.**.***.**.....
LUBEOIL CAPACITY (U.S.STD.)
l o**o***************b
I
2-5/8x 3"
65
5 Quarts
7.5Quarts
5 Quarts
14mn
.025"*
018
II
.018
22.ft."1bs.
.Ol5"
2-5/8x 2-3/4"
59.4
4 Quarts
7.0Quarts
5 Quarts
14mn
.025"
018
II
.
078
22.ft.Y;bs.
.015"
RADIATORCAPACITY (U.S. STD.> l *.**.****.*******.**
MARINE(CLOSED) COOLING CAPACITY l **********o*******
SPARKPtUG SIZE (USEJ-8OR EQUIVALENT)
l **********
SPARK PLUG GAP (STD.PLUG- GASOLINE) i............
SPARKPLUG GAP (STD.PLUG- GAS)
l ****e************
SPARK PLUG GAP (SHIELDED PLUGS)
l ******************
PLUGTIGHTENINGTORQUE
l ***o******************o****e
BREAKERPOINTGAP .(INSIDEMAGNETO)
l ***************
HOSE
- THERM0
HOSE
PUMPTO ADAPTER
INLET (TOP) TO TOPOF
FOLD
HSG.
MAN1
ADAPT HOSE - ADAPTER
TO EXHAUST
MIXER
WATERPUMP.
SEA
WATER II /u
INLET
EXHAUST II
YIXER
WATERCOOLED
EXHAUSTOUTLET
FORl-3/4"I.D.
FIGURE1-4 -- CARBURETORSIDEVIEW- TYPICALMARINEGENERATORSET
SERVICE SCHEDULE
PERFORMSERVICEAT INTERVALSIMIICATED (X) EVERY I EVERY
'
100HOtlRS 200 HOURS
(OR 6 MONTHS) (OR YEARLY)
Checkoillevel
-----------------------------
X
Checkcoolantlevel
-------------------------
X
Check conditionof compartment----------
----X
Checkvalve clearance-------------------
Checkbreakerpoints
Checkignitiontiming
Clean crankcasebreather----------------
Checkgenerator brushes-----------------
Change oil ------------------------------ a--------- -------X
Check fanbeltandtension ------------- ---------- -------X
Check air intakesilencer---------------
----------
-------X
Checksparkplugs
-----------------------
-------------------------
Checkelectrolytelevelin battery----i-
----------
---------------
Checkelectrical
connections ------------ ---------- ---------------
NOTE: Intervak stated are for norm2 operatingco7uiitims--performservCcesmore fretpenttyunder
servere conditions.
. 14
8

LUBRICATION
LUBRICATING OIL -
TO be on the safe side, check oil in engine crankcase before each start to insure that the level
is between the L and F marks on dipstick. Do not operate plant if level exceeds the *‘F1’ mark or if
below **L*l marnove oil filler-breather cap and add oil here. Use only 03s meeting the require-
ments of the American Petroleum Institutes (API) Service classification SC. Oils with this classifica-
tion are detergent type oils. The classification is usually stamped or printed on the oil cans.
SERVICE Use SAE 30 weight for temperatures above 30* F.
--~~~~~~~~~~~~~~~~~~~~~-~~~~~~~~~~~~~~~~~~-
SC Use SAE 10 weight for temperatures below 30’ F.
On a new plant, change oil after the first 5 hours of operation and thereafter at 50 hour
every 6 months--whichever occurs first), Change oil more frequently if plant -operated
under extremely dusty or dirty conditions. Whenever possible, drain oil while hot as it will flow more
freely and carry away a greater amount of contamination. .
20 PSI NORMAL
ACORN NUT
(NOT USEDON
SOMEMODELS) PRESSUREADJUSTINGSCREW
. FIGURE2-l --NORMALOILPRESSUREANDADJUSTMENT
OIL PRESSURE ADJUSTMENT .
Oil Pressure: After the engine has been thoroughly warme d up and is operating with proper weight of
011 in crankcase, the oil pressure should be about 20 psi. An external oil press ure adjusting screw is
provided on the crankcase just below and to the rear of the carburetor. Lf norm al operating pressure
is lower than 20 psi, remove acorn nut, loosen lock nut then turn screw until pressure is correct.
Secure lock nut at new setting and reinstall protective acorn nut. When engine is cold, pressure may
be as high as 50 - 60 psi but should gradually return to about 20 psi as the engine warms up.
OIL FILLER - BREATHER CAP
After about every fourth oil change (200 hours), service oil filler-breather cap. DO this more
of&n under dusty, dirty conditions. A clogged breather can lead to build up of abnormal crankcase
pressures and result in l’eakage around seals, gaskets, etc.
Service breather by washing in solvent such as kerosene --swish element in solvent to dislodge
dirt. After cleaning, allow a few moments for it to drip dry then apply light amount of oil to the mesh
eleme’nt. Use same weight and grade of oil as used in engine. Always make sure cap is in place before
placing engine in operation.

.
- FILLER -
l
CARTRIDGE
TYPE
RUBBER
SEAL
\
MOUNTINGGASKET
(DON’T REVERSE
POSITION TO
BLOCKOIL HOLES)
FIGURE2-2 -- OIL FILLER - BREATHER FIGURE2-3 -- OPTIONALOIL FILTER
OIL FILTER - OPTION
.
If your engine is equipped with the 0p tional oil filter, change the filter cartridge after each 200
hours of operation. This should be done at the same time
change. Wrap rags the oil 1s drained during every fourth oil
around the base and use pan to catch any oil trapped in the cartridge. Twist car-
tridge off by hand- turn in counterclockwise direction to remove.
engine oil isreplen,ished and engine is again placed in operation, l&d tighten new cartridge--‘after
leakage--retighten element as needed to stop leaks. check area around filter for signs of
Doa? use substitute cartridge elements for replace-
ment-use only genuine Kohler parts.
If the engine does not have a filter but is operating in high dust, dirt areas, the oil filter feature
can be quickly added. Simply remove the two plugs from the filter mounting, position a new gasket on
the pad (make sure holes in gasket match oil holes) and secure the filter assembly with 4 capscrews. *
3
22
l
..
.

AIR INTAKE
I
AIR CLEANER SERVICE .
An air cleaner must be maintained in proper condition to insure satisfactory performance and
prolonged engine life. Operating with an !‘overrich” fuel mixture caused by a poorly serviced, clogged
air cleaner leads to formation of harmful sludge deposits. An inadequate element or improperly
installed air cleaner permits entrance of dirt which can wear out piston rings in a very short time.
The service intervals stited for air cleaners are for good clean conditions--service cleaners more
frequently under dusty or dirty conditions (even daily, if extreme conditions warrant this). Dry and oil
bath type cleaners are used --carefully follow instructions for type in use. A flame arrestor type
cleaner is used on many marine models.
DRY TYPE AIR CLEANER
Replace-element after 100-200 hours if operating under gdod clean air conditions--sooner in dusty,
dirty conditions. Use only genuine kohlerreplacement elements of correct part number.
Every 50 hours (or 3 months), remove element and lightly tap rubber rim against flat surface to
dislodge any loose dust from surface. Replace element if it has too many dark spots or extensive dark
area as this indicates dirt trapped in the filter material. Do not wash dry element in any liquid or
attempt to clean element with air hose as this will ruin or rupture the paper fiber material. When
handling element, avoid crushing material or bending element as this co&d allow unfiltered air to
enter the engine --note a’ir flow shown in the figure below.
When installing a new or serviced element, make sure rubber gasket surfaces are flat against the
filter base and cover --secure wing nut (with washer in place when used) finger tight--washer is not
required with plastic type wing nuts.
.
~~ -~
FIGURE 3-7 -- CIRCULATIONTHRUDRYAIR CLEANER
(WASHERNOT
REQUIRED
UNDERPLASTIC
TYPE)
AIR
BASE
FIGURE3-2 ,- TYPICAL DRYTYPE AIR CLEANER

1 cup-
I
’ .
I
I
OIL
LEVEL
BEAD I I
I
FIGURE3-3 -- OIL BATHTYPE AIR CLEANERS
OIL BATH TYPE AIR CLEANERS
There are several different types of oil bath air cleaners in use; however, the same general ser-
vice recommendations apply to all. After every 50 hours operation (or every third month) remove oil
bowl, clean out dirty oil, fill to level indicated with same grade of oil used inengine or, with see thru
‘SAF-T-VUP type use SAE 40 in summer, SAE 20 in winter.
Every 100 hours (or more often under severe conditions) service the filter element. On types
shown above, as A & B, remove bowl and breather hose then disconnect air cleaner with elbow attached
at the c’arburetor --do not attempt to separate cleaner from the elbow.
in solvent such as kerosene, On all types, swish element unit
then allow it to drip dry before reinstalling. Service oil bowl as described
in the foregoing.
FLAME ARRESTOR (NiARlNE MODELS)
Marine Models use an approved flame arrestor which also serves as an air cleaner to a certain
degree. This unit does not require regular service because of the clean operating conditions normally
encountered in marine applications. When the element starts to appear dirty, disassemble the unit and
swish element in a cleaning solvent that does not leave a film,
ing on the engine. Keep the element dry--do not oil. then allow it to drip dry before reinstall-
Make sure parts are reassembled exactly as
shown below to insure that the unit can function as a flame arrestor.
COVER
FIGURE 3-4 -- FLAME ARRESTOR FOR MARINE MODELS
32
l

FUEL SYSTEMS
GENERAL .
Carburetor Adjustment: The following procedure covers the initial adjustment of both. up draft and side
draft type carburetors. An idle adjusting needle is provided on the horizontal carburetor even though
engine operates at idle speed only for a brief moment as it comes up to speed after it is started or when
it slows after being shut down- the idle adjustment is therefore not critical and can be permanently set
at 2 turns open. The up draft type carburetor does not have an idle adjustment.
CARBURETORS - GASOLINE
Carburetors are adjusted in the factory and readjustment is not normally needed unless plant is
operated at a much higher altitude or if carburetor problems develop after extended usage. If engine
misses and backfires, this could indicate carburetor is see too lean. If black, sooty exhaust smoke is .
noted and engine is sluggish, the fuel mixture is probably set too rich. Do not neglect carburetor prob-
lems for continued operation with improperly adjusted or dirty carburetor can result in overheating,
fouling of spark plugs, excessive valve wear and other problems.
HIGHSPEED I- THROTTLELINKAGE
STOP
FUEL
INLET
l-1/2 TURNSOPEN
MAIN FUEL -
2-l/2 TURNSOPEN
INIir
FUEL
INLET
IDLE FUEL
-2 TURNS
FIGURE4-7 -- TYPICALUPDRAFT’CARBURETOR FIGURE4-2 -- TYPICALSIDEDRAFTCARBURETOR
STEP 1 -
STEP 2 -
STEP 3 -
STEP 4-0
Stop engine and carefully turn Main Fuel adjustment all the way in (clockwise) until the needle
bottoms lightly- do not force as this will damage needle or seat.
For preliminary adjustment, turn Main Fuel adjustment out (counterclockwise direction)
2-l/2 turns on side draft carburetor or l-1/2 turns open on up draft carburetor.
Start engine and allow it to warm up to normal operating temperatures. Place engine under
normal load when- making final adjustment.
For final adjustment, move Main Fuel needle in until engine starts to slow down from too lean
a mixture (note position), then back out until speed increases--continue turning richer until
speed again starts to drop from overrich setting then turn needle back in until it is positioned
about halfway between lean and overrich settings.
Carburetor Reconditioning: If readjustment does not remedy problems attributed to carburetor, car-
buretor should be dzsassembled and reconditioned. Always use carburetor repair kit for best recon-
ditioning results. After carburetor is completely disassembled, all metal parts should be cleaned in a
solvent such as alcohol or aketone or commercial cleaner which readily remove gum and carbon deposits.
Blow out all passages with compressed air and replace all gaskets and worn parts. Repair kits contain
essential parts. Disassembly and reassembly of carburetors is accomplished as follows:
. 41a

Disassembly of Carburetor - Up Draft
1. After removing carburetor from engine, remove 4 capscrews and separate throttle body (includes
float) from lower carburetor body. .
2. Remove float pin, float and body gasket. Remove fuel inlet needle. Check needle for damage and
float ior dents, leakage or excessive wear on lever or in hinged area.
3. Remove throttle plate retaining screw (and lock washer) then slip plate out of slot in shaft. Slide
throttle shaft out of body. Inspect bushing and shaft -- unfiltered air could enter in this area if
worn.
4. Remove main fuel needle - inspect for wear or damage.
clean venturi and fuel bowl areas. Blow out main fuel nozzle, thoroughly
.
5. Do not remove choke plate or choke shaft uhless loose or damaged. Further disassembly of lower
body is not normally necessary. .
.
Reassembly of Carburetor - Up Draft
Reassembly is essentially the reverse of the disassembly procedure. Special instructions are
needed, however, to properly set the level of float before throttle body is reinstalled to carburetor body.
Float: Level; Turn throttle body upside down, install new gasket and fuel inlet needle then position float
and insert float pin. With float lever resting on inlet needle, measure distance between gasket and
bottom of float at free end. The distance should .be S/16*’ - if adjustment is needed, carefully bend
float lever to attain proper level. After carburetor is reinstalled on engine, recheck for proper level
by removing fuel level plug - if properly s&t, fuel level should be just below this hole.
THROTfLEPLATE 0 THROTTLE
- SHAFT
.
.
GASKET,UPQER BODY
CARBURETOR,
UPPERBODY
.
VENTURI
GASKETs
FLOAT(GASOLINE)
ILE & SEAT
SHUTTER(PLATE)
.
CHOKESHAFT
CARBURETOR,
LOWERBODY
1.
MAINFUELADJUSTINGNEEDLE
FIGURE4-3-- _ EXPLODEDVIEM- TYPICALUPDRAFTCARBURETOR
. 42
l

CARBURETORBODY
BOGI RINGGASKET
-FUEL BOWL
BAFFLE
- \ BOWLRETAINER
MAIN FUEL
._____- --- .
NEEDLE& SEAT WGY
#,/SCREW & GASKET
SHAFT& PLATE
1 FUELFLOAT
FIGURE4-4 -- EXPLODEDVIEW- TYPICAL
SIDEDRAn CARBURETOR
Disassembly of Carburetor - Side Draft . .
1. Remove carburetor from engine.
2. Remove bowl nut, gasket and bowl. When carburetor has bowl drain, remove drain spring, spacer
(when’used) plug and’gasket from inside of bowl. .
.
3. Remove float pin, float, needle and needle seat. Check float for dents, leaks and wear on float
lip or in float pin holes.
4. Remove bowl ring gasket.
5. Remove idle fuel adjusting needle, main fuel adjusting needle and springs.
6. Do not remove choke and throttle plates and shafts.
Iftheseparts are worn, replace carburetor
assembly.
Assemblv of Carburetor - Side Draft
1. Install needle seat, needle, float and float pin. .
2. Set float level. With carburetor casting inverted and float resting lightly against needle in its
seat, there should be 11/641Vplus or minus l/32 of an inch clearance between machined surface
of casting and free end of float (side opposite needle seat). l
3. Adjust by bending lip of float with small screwdriver.
. . .
4. Install new bowl ring gasket, new bowl nut gasket (when required)and bowl nut. Tighten securely
after making sure bowl is centered on gasket.
5. Install main fuel adjustment needle. Turn in until needle seats in nozzle and back out two turns.
6. Install idle fuel adjustment needle. Back out approximately l-1/2 turns after seating lightly against
jet. CAUTION: DO NOT USE: FORCE ON ADJUSTMENT NEEDLES. .
.

GASOLINE FUEL PUMP
The fuel pump does not require regular service but may have to be rebuilt to restore normal
efficiency after extended hours of operation. If your engine falters or stumbles each time the load is
increased, this may be due to a worn-out fuel pump. The repair kit listed in the parts manual for this
pump includes all parts necessary to restore normal efficiency of the fuel pump. Remove fuel pump
from engine and rebuild as follows:
DISASSEMBLY
_
STEP 1: Scribe matching marks .on fuel head and pump body before disassembly.
STEP 2: Remove cover capscrew and cover. Discard cover gasket.
STEP 3: Remove 6 screws from around perimeter of fuel head, then separate head from body.
Note direction of valves then press old fuel valves out of fuel head--discard valves
and valve gaskets.
GASKET-/ m
es
PUMP 53 COVER :DIAPHRAGM
I -f !
3
a I m
'VALVE i SEAL- x
L-ARM SPRING v? PUMPBODYa
n
NOTE: Primer lever is spring
‘r&d to DUZZ back into
position At to engine-
if it sticksin the atended
position,t?& diaphmgm cm-
notoperateto pump fbeZ.
Make su2-wteverretums to
properposCtion.
. FIGURE 4-5 -- FUEL PUMPEXPLODEDAND
CUTAWAYVIEWS
STEP 4: To disassemble pump body, first insert screw driver blade into coils of pump arm
spring and compress spring to remove. Next com.press the diaphragm spring then
lift the link to disconriect and remove the diaphragm and oil seal--discard these
parts. Push pin out to release pump arm and link to complete disassembly.
RECONDITIONING
Wash fuel head, body and cover in gasoline and clean with stiff bristle brush. Make sure all
traces of gasket material is removed from surfaces. Recondition components as follows:
FUEL HEAD: Position new valve gaskets then press new valves from kit into place. Position new
cover gasket on head, then install cover and tighten capscrew.
PUMP BODY: Position link and pump arm, the- install and stake new pin. Place new oil seal and
spring then install n&w diaphragm assembly and hook it to the arm link. Replace pump arm spring.
Don’t reassemble the body to the fuel head at this time. /.- *
INSTALLATION ON ENGINE
To attain proper operation of the rebuilt pump be sure to follow this reinstallation procedure.
.
STEP 1: Use a new pump body gasket then reinstall pump body assembly on engine. Turn
engine until diaphragm is flat against the pump body then position fuel head (with
scribe marks aligned), then temporarily tighten the six screws only about three
turns--again turn the engine until the diaphragm pulls down into the body then
securely tighten the six screws. After this is done, reconnect fuel lines to com-
plete the reinstallation. .
44
0

. INSERT#43 DRILL
IN NOTCH
LOOSEN
CLAMPBOLT
TOAD&
CONTROLLERLEAD(S)- A?V An\- ---- -- -_- --,-,
*(SIkLEOR DOUBLE
WmE UNIT USED--
NOT INZZRC'KAIVGEABLE)
LEVERUPTO
#EASECHOKE
UP - INCREASE
DOWN-
DECREASE
FORADJUSTING
KECROSSSHAFT
BASE OF CHOKEBODY
-_a._-- 1 m .__..__A. _ .AA ..L. -_a _L - - ~ -
FIGURE4-6 -- MANIFOLD MOUNTED TYPE AUTOMATICCHOKE
AUTOMATIC CHOKES
. Two different electric - thermostatic type automatic chokes are used. One type is an integral
part of the carburetor while the other type is mounted on the exhaust manifold and connected through
external linkage to the choke plate in carburetor. The electrical leads to the choke are connected so
that current flows to the thermostatic element only when the ignition is turned on. Tension of the
thermostatic spring is set to atlow full choke at starting. On manifold type, heat from the manifold con-
trols tension of the thermostat spring which causes the choke plate to be gradually returned to the open
position as the engine warms up. On carburetor units, vacuum from intake manifold pulls the choke
open. Chokes are adjusted in the factory, however, slight readjustment may be necessary initially to
account for different starting conditions. Adjust chokes as foUows:
Carburetor Unit: Choke unit is set for average conditions. To readjust, loosen three screws on outside
of cover plate then shift cover in clockwise direction (arrow) for richer setting or in counterclockwise
direction for leaner setting. Tighten cover screws after final adjustment.
Exhaust Manifold Mounted Unit: Remove air cleaner from carburetor to observe position of choke plate.
aoke adjustment must be made on cold engine. If starting in extreme cold, choke should be in full
closed position before engine is started. A lesser degree of choking is needed in milder temperatures.
.
If adjustment is needed, proceed as follows:
7. Move choke.arm until hole in brass shaft lines up with slot in bearings.
2. Insert #43 dri 11 (l 089) and push al 1 the way down to engine manifold
to engage in notch in base of choke unit.
3. Loosen clamp bolt on choke lever, push arm upward to move choke plate toward closed
* position. After desired position is attained, tighten clamp bolt then remove dri'll.
SPRiNG
PLACEMENT
WRONG RI&IT I
I
1.-~~~~~~~-~~~~-----~~
INITIAL SETTING
ONCENTERNOTCH
INTAKEMANIFOLD
-- _ -
FIGURE4-7 -- __-
CARBURETORMOUNTEDTYPE AUTOMATICCHOKE

_
GAS SYSTEMS l
Natural gas supplied from main transmission line is normally received at pressures not greater
than 51) pounds per square inch (psi) while with LPG, which is Butane or Propane or usually a mixture
of the two gases, the pressure may go as high as 180-200 psi depending on the mix ratio and tempera-
ture. To be used by the engine the pressure must be reduced to.ounce values. The reduction is nor- s
mally accomplished in two stages by a primary regulator which reduc line pressures to about 6 ounces
per square inch and a secondary low pressure regulator which further reduces the pressure in accord-
ance with engine demand. The primary regulator is often furnished by the fuel supplier. The fuel
supplier should also insure that gas pressure is sufficient to operate the primary regulator. If pressure
drops too low, the regulator may not function at all. - While propane, for example, tends to maintain
some vaporizing pressure even at temperatures down to -20’ F. , butane returns to liquid state and
offers little or no vapor pressure when the temperature drops to freezing or 32O F. For this ‘reason,
fuel suppliers usually supply LPG of higher butane content in hot weather but will alter this to a higher
percentage of propane during cold weather. If this ratio is not changed, starting and operating difficul-
ties may be encountered in cold weather.
Straight gas and combination gas/gasoline systems are used. The combination system uses a gas
mixer or adapter attached to a standard gasoline carburetor.
and regulators are discussed in the following. Some common carburetors, adapters,
GAS CARBURETORS - ADAPTERS
In a venturi type carburetor, the gas nozzle is located at the point of greatest pressure drop inside
the venturi. This creates a suction within that nozzle that varies with changing rate of air flow and
causes a greater volume of gas to be metered at heavier loads and a lower volume at lighter engine load.
The throttle valve regulates the rate of air flow through the carburetor.
this valve is wide open and offers ‘little restriction to air flow. When an engine is at top speed,
Closing the throttle causes a decrease
in air flow and lowers engine speed and power. As the valve closes, it reduces pressure through the
venturi and past the fuel nozzle.
On engines with the gasoline carburetor, an adapter with venturi is installed between the carbure-
tor and air cleaner. The adapter consists of a gas jet and venturi. Accurdte metering of the gas is
accomplished by load and starting or idle adjustment screws in the body of the adapter.
Most gas carburetors are simple devices having only one moving part--the throttle shaft and
plate (or butterfly valve as it is sometimes called). Because of this, they should require very little
attention and readjustment should seldom be needed. If needles wear out or venturi is damaged, these
I
IDLE FUEL BREATHER.
TUBETO
VALVECOVER
IDLE
SPEED
ADJUSTMENT
JdAINFUEL
.
SECONDARY
GAS REGULATOR
(MODELUN)
-=--ii& OIL BATH
I
TYPE AIR
CLEANER
(3/4” NPT
FROMPRIMARYREGULATOR)
.
FIGURE4-8 -- TYPICALSTRAIGHTGAS FUEL SYSTEM
46
l

GASOLINE
CARBURETOR
GASIN
3/4NP
GASLINE
(FLEXIBLE)
\
LET
(GAS)LOADADJUSTME
SECONDARY REGULATOR
T - - (MODELUN]
ti FUELPUMP
u\ PRIMINGLEVER
(GASOLINE)
NT
FIGURE4-9--TYPICALGAS-GASOLINEFUELSYSTEM
can be replaced. After replacing these parts, use the following procedure’ to adjust carburetor.
1. Turn the idle stop screw in about 2 turns or until the butterfly valve is held slightly open.
2. Turn IDLE FUEL screw (gas carburetor only) all the way in until it bottoms lightly.
3. Turn the MAIN FUEL or LOAD screw all the way cl.osed then back out 5 turns for initial setting.
After preliminary adjustments are made,
runs smoothest at governed speed no load, start the engine and adjust the MAIN FUEL until the engine
for final power adjustment. then put the engine under normal load and readjust as needed
The idle fuel adjustment can remain completely closed if the engine is not
required to run at any other speed than load speed. a
On the combination systems, use the same general procedure as stated for adjusting the gas
adapter and that stated earlier for adjusting the gasoline carburetor.
GAS REGULATOR -- MODEL KN SECONDARY
. The orifice size and maximum inlet pressure are stamped on the cover of the KN-do not permit
inlet pressure to exceed maximum (usually’6 oz.). If an electric solenoid is used, it should be mounted
close to the model KN.
To check inlet pressure, The orifice size of the s.olenoid must be at least as large as orifice in regulator.
remove plug on fuel inlet,
inlet pressure to 4-7 ounces (t-12*’ water column) insert manometer or ounce pressure gauge. Adjust ,
--inlet pressure is adjusted on primary regulator.
Reconditioning: Thoroughly wash all metal parts in cleaning solution, blow out all passages. Replace
all worn, damaged parts. Inspect diaphragm and gaskets bonded to both sides of diaphragm--replace as
unit if diaphragm or gasket damage is evident. Check brass orifice--replace if nicked. Replace rubber
seat if crushed or if foreign material imbedded in rubber.
all parts are clean and free of dirt, lint, etc. Before. reassembling regulator, make sure
Adjustment (Lock Off): The lock off adjustment is provided only to shut off fuel when engine is not oper-
ating-it is not for adjusting fuel mixture or engine speed. Readjustment should be necessary only after
47l

. ORIFICE
FIGURE4-I 0 -- MODELKN SECONDARYGAS REGULATOR- EXPLODEDVIEGI
regulator has been completely disassembled or if fuel is not being shut off properly after engine stops.
Use following procedure to adjust:
With engine stopped, slowly turn lock off screw out (counterclockwise direction) until
fuel starts to flow through the regulator then turn screw i’n (clockwise) until the flow stops--
note position of screw when flow stops then turn in one more turn for final setting.
480

IGNITION SYSTEM
Several factors contribute to the overall performance of an ignition system - all components must
be in good condition and the spark must be properly timed. Hard starting, low power and erratic opera-
tion can often be attributed to faulty ignition. If poor ignition is suspected, the first thing to do is to
determine if this system is actually at fault. A simple operational test will determine this.
OPERATIONAL TEST: Remove the high tension lead at the spark plug, bend paper clip and insert into
boot then hold the end about l/16” to l/8*! away (with insulated pliers to prevent electrical shock) from
the cylinder head while cranking the engine. If a sharp snappy spark occurs, the trouble is apparently
not in the magneto although it could still be attributed to a poor spark plug. If no spark or a very weak
spark occurs, ignition trouble is indicated. When checking out an ignition system, the components most
commonly requiring service or adjustment should be checked first.
TO
ENGINE FlRliG ORDER
l-3-4-2
I
ON STANDARD
PLUGSAT .025"
I
FIGURE5-l -- HIGH TENSIONLEADCONNECTIONS- STANDARDMAGNETO
SPARK PLUG SERVICE
Engine misfire or generally poor operation is often caused by spark plugs in poor condition or
with improper gap setiing. Plugs fail for various reasons. Often the porcelain insulator cracks or
becomes coated with oil, carbon or other deposits which causes the high voltage ignition impulse to
pass from the center electrode to ground without jumping the plug gap. As’an engine operates, the
electrodes are gradually burned or worn away. In time, the gap becomes so wide that the available
ignition voltage cannot jump the gap and the engine misses.
Spark Plug Service: Every 100 hours, remove plug, check condition and reset gap. Good operating
conditions are indicated if plugs have a light coating of gray or tan deposit. A dead white, blistered
coating could indicate overheating. A black (carbon) coating may indicate an *roverrichJt fuel mixture
caused by clogged air cleaner or improper carburetor adjustment. Do not sandblast, wire brush, scrape
or otherwise service plug in poor condition - best results are obtainmh new plug. Use Champion 58
or equivalent spark plugs with standard ignition and Kohler #24Q705-S with the shielded ignition system.
For gasoline operation, set spark plug gap at .025*‘, or at .018” on gas fuel and on shielded plugs.
Tighten plugs to 22 ft. tbs. torque.
51
l

MAGNETO ’ -
Two different magnetosare in use on these engines- the standard type is shown on page 5.1 and
the optional radio shielded type is shown below. Both are flange mounted on the front support plate and
. driven off an idler gear which is, in turn, driven off the crankshaft gear. The breaker points, coil and
condenser are located inside the unit. A built-in impulse coupling imparts a strong spark for starting
when rotational speeds are low. Avoid removing magneto from the engine since it must be retimed to
the engine when reinstalled- this should be done only by a qualified mechanic.
Magneto Service: After each 500 hours of operation, remove magneto end cap and check condition of
breaker points-- if dirty, clean with lacquer thinner and a coarse (lint free) cloth.
. If slight amount of
pitting and metal transfer is noted, dress contacts with tungsten file or a fine stone. Replace points if
badly worn or pitted. Reset gap as follows after servicing or replacing points:
1. Turn engine over until points are wide open (at highest point on cam). Maximum opening should
be .OlP. Proceed with Step 2 if adjustment is necessary.
2. Loosen clamp screws slightly so that contact plate can be moved --insert blade in adjusting slot
then shift plate until . 019 maximum clearance is measured between contacts. Retighten clamps
after adjustment. .
3. Lubricate cam wick with Rycon grease each time breaker points are serviced.
Wiring: When viewed from the terminal end, the standard unit rotates in a clockwise direction while
the shielded unit rotates in the opposite direction. The number 1 terminal is marked on each end cap.
Firing order of the engine is 1 - 3 - 4 - 2. Refer to Figure 5-l for proper connection of the high ten-
sion leads from the standard type magneto to spark plugs --refer to Figure below for connections to
shielded type magneto. The leads must be properly connected to make the engine fire in the correct
order.
SHIELDED
MAGNETO
(TOPVIEW)
TO 85 TERMINAL
IN CONTROLLER
TO # 2
PLUG
TO # 1
PLUG
r-
SETGAPON SHIELDED
PLUGSAT .018" I
TO # 4
PLUG
TO iy3
PLUG
FIGURE5-2--
WIRINGCONNECTIONS- SHIELDEDTYPEMAGNETO
. 52a

END CAP-
ROTOR
1
~flISTRIBUTOR CAP lJLlnIL3 \
. FIGURE5-3 -- *BREAKERPOINT SERVICE- STANDARDMAGNETO
INSTALLING MAGNETO
Timing Standard Magneto To Engine: The magneto is timed to the engine at the factory - retiming should
not be necessary unless unit has been removed fr’om the engine for reconditioning or other reasons.
Use the following steps to retime magneto to engine:
1. Turn engine over until SPK mark on flywheel - generator fan is lined up with timing line and
pointer on the bell housing. (Remove # 1 spark plug--c heck to insure #l cylinder is at top of
compression stroke. )
2..
.
On magnetos with timing window, turn magneto gear (counterclockwise) until white mark lines up
with indicator. This positions distributor for firing #l spark plug--hold in this position.
3. Position gasket then carefully guide magneto gear into engagement with idler gear--make sure whir
timing mark remains centered when installing. Secure magneto to engine.
4. Reconnect high tension leads then check ignition timing with timing light.
Timing Shielded Magneto To Engine: Use the following procedure to insure that shielded magneto is in
time when reinstalled to engme.
STEP 1 -
STEP 2 -
STEP 3 - Make sure #I timing position of both engine and magneto are held while magneto is installed
on engine. Connect leads as shown in the accompanying illustration for shielded type magneto.
Make sure ground strap is connected to controller terminal #5. Install radio shielded plugs.
STEP 4 - After completing installation, use timing light for precision timing of the ignition.
To establish firing position of # 1 cylinder, rotate engine by hand until timing mark on genera-
tor fan (SPK) lines up with timing mark (line) on generator housing and compression is felt in
#I cylinder (place thumb over spark plug hole).
To establish #l firing position of magneto, connect lead.to magneto terminal marked # 1.
Carefully hold end of this lead about l/W away from case and turn magneto gear in clockwise
(viewed from gear end) direction through each impulse release. Considerable resistance
will be felt as the coupling approaches the trip point and a loud click will be heard as it
releases. Continue turning until spark is observed between #l lead and the case, then turn
gear backwards (counterclockwise) until notch in gear (and hud) lines up with yellow timing
mark on magneto flange.
53
l

IGNITION TIMING (MAcsNET~).
Timing Magneto Ignition: For precision timing, use timing light per instructions furnished by the light
manufacturer. Do not connect a battery to the magneto as this will ruin the coil windings. To time
ignition, proceed as follows:
1. After making sure breaker point gap is properly set, connect timing light to #l cylinder then
start engine.
2.
3.
Aim timing light into.pointer area on bell housing. SPK mark should be even with the pointer just
as the light flashes. If it is not, proceed with Step 3.
To adjust timing, loosen (do not remove) the two magneto mounting capscrews-shift position of
magneto (top flange eccentric) until SPK mark is exactly centered. After proper timing is
attained, retighten mounting capscrews.
#4 SPARK
.
ENGINE FIRING ORDER
1-3-4-2
FIGURES-4-eBATTERY IGNITIONSYSTEM
BATTERY (DISTRIBUTOR) IGNITION ’
DISTRIBUTOR SERVICE: After each 500 hours of operation,
dition of the breaker points. If points are dirty. remove distributor cap and check con-
cloth. Replace points if badly worn or pitted. clean with lacquer thinner and a coarse (lint free)
opening is a maximum-- To adjust point gap. turn engine over until point
point gap should be set at . 020rf. Check and adjust gap after servicing or
replacing points.
m Every 500 hours, remove the plug on the distributor housing and the plug on the drive housing as
shown-fill reservoirs with SAE 20 weight oil. Reinstall plugs after se&&g. Distributor rot& .
turns in clockwise direction when viewed from the top. The number 1 terminal is indicated above- *
connect spark plug leads as shown for proper firing sequence.
_ _ a Use the following procedure if dis-
tributor
STEP I:
STEP 2:
STEP 3:
retiming becomes necessary,
To establish firing position of #I cylinder, rotate engine by hand until timing mark on gen-
erator fan (SPK) Lines up with timing mark (Line) on generator housing and compression is
felt in #l cylinder (place thumb over spark plug hole).
With distributor removed from engine, remove distributor cap, rotor and cover. Reinstall
rotor and rotate drive gear until ignition points just begin to open when rotor is positioned
to fire #l spark plug, .
Install distributor on engine. Reassemble cover, rotor and cap in proper position. Connect
spark plug leads as indicated, use timing light for precision timing of the ignition.