Tecumseh VH80, HH80, VH100, OH120-180 User Manual
TECUMSEH
T E C H N I C I A N ' S H A N D B O O K
This manual covers the following models:
VH80, VH100, HH80, HH100, HH120, OH120-180
Model numbers are located on the engine shroud.
Other illustrated Tecumseh 2-Cycle Engine, 4-Cycle Engine
and Transmission manuals; booklets; and wall charts are
available through Tecumseh.
For complete listing write or call
8 TO 18 HP
CAST IRON
FOUR CYCLE
ENGINES
Contents
Page
CHAPTER 1. GENERAL INFORMATION ...................................................................................................................................1
SECTION 1. ENGINE IDENTIFICATION .............................................................................................................................1
SECTION 2. ENGINE CARE ...............................................................................................................................................2
CHAPTER 2. AIR CLEANERS, CARBURETORS, GOVERNORS AND LINKAGE................................................................... 4
SECTION 1. AIR CLEANERS..............................................................................................................................................4
SECTION 2. GENERAL CARBURETOR INFORMATION..................................................................................................5
SECTION 3. TECUMSEH CARBURETORS .......................................................................................................................6
SECTION 4. WALBRO CARBURETORS..........................................................................................................................10
HH80 - 120, VH80 - 100 ..............................................................................................................................................10
SECTION 5. OVERHEAD VALVE ENGINE CARBURETORS ..........................................................................................13
SECTION 6. GOVERNORS ............................................................................................................................................... 1 6
SECTION 7. IMPULSE FUEL PUMP.................................................................................................................................19
CHAPTER 3. REWIND STARTERS, ELECTRIC STARTERS, TROUBLESHOOTING AND GENERATORS......................... 20
SECTION 1. REWIND STARTERS .................................................................................................................................... 2 0
SECTION 2. ELECTRIC STARTERS ................................................................................................................................22
SECTION 3. 12 VOLT STARTER TROUBLE SHOOTING CHART...................................................................................25
CHAPTER 4. GENERAL VALVE INFORMATION, CYLINDER HEAD AND BREATHER ASSEMBLY ................................... 27
SECTION 1. GENERAL VALVE INFORMATION...............................................................................................................27
SECTION 2. CYLINDER HEAD .........................................................................................................................................31
SECTION 3. BREATHER ASSEMBLIES ...........................................................................................................................32
CHAPTER 5. PISTON AND RINGS, CONNECTING RODS AND CRANKSHAFTS................................................................33
SECTION 1. PISTON AND RINGS....................................................................................................................................33
SECTION 2. CONNECTING RODS...................................................................................................................................35
SECTION 3. CRANKSHAFTS ...........................................................................................................................................36
CHAPTER 6. CAMSHAFT, BEARINGS AND SEALS...............................................................................................................37
SECTION 1. CAMSHAFT ..................................................................................................................................................37
SECTION 2. BEARINGS....................................................................................................................................................38
SECTION 3. SEALS...........................................................................................................................................................42
CHAPTER 7. DYNA-ST ATIC® BALANCING SYSTEM .............................................................................................................43
CHAPTER 8. IGNITION SYSTEMS, CHARGING SYSTEMS BATTERY SERVICE and
ELECTRICAL CONTROL P ANELS ..........................................................................................................................................45
SECTION 1. IGNITION SYSTEMS ....................................................................................................................................45
SECTION 2. CHARGING SYSTEMS.................................................................................................................................48
SECTION 3. BATTERY SERVICE .....................................................................................................................................53
SECTION 4. ELECTRICAL CONTROL PANELS ..............................................................................................................56
CHAPTER 9. TROUBLESHOOTING ........................................................................................................................................61
CHAPTER 10. 8 H.P. & LARGER ENGINE SPECIFICATIONS AND TORQUES ....................................................................66
SECTION 1. CROSS REFERENCE LIST FOR TABLE OF SPECIFICATIONS................................................................66
SECTION 2. TORQUE SPECIFICATIONS ........................................................................................................................70
8 H.P. & LARGER ENGINES (EXCEPT VALVE-IN-HEAD).........................................................................................70
SECTION 3. VALVE-IN-HEAD ENGINE SPECIFICATIONS ............................................................................................. 7 1
SECTION 4. TORQUE SPECIFICATIONS ........................................................................................................................73
VALVE-IN-HEAD.......................................................................................................................................................... 73
CHAPTER 11. EDUCATIONAL MATERIALS AND TOOLS.................................................................................... ..................74
C Tecumseh Products Company
1998
i
CHAPTER 1. GENERAL INFORMATION
SECTION 1. ENGINE IDENTIFICATION
Tecumseh engine model numbers are stamped into
the blower housing, or are located on a nameplate
or tag on the engine in locations as illustrated.
OH160-170033 SER 8044C
INTERPRET ATION OF MODEL NUMBER. The first
letter designations in a model number indicate the
basic type of engine.
SHORT BLOCKS. New short blocks are identified
by a tag marked SBH (Short Block Horizontal) or
SBV (Short Block Vertical). Original model tags of
engines should always be transferred to a short block
for correct parts identification.
HH - Horizontal-Heavy Duty (Cast Iron)
VH - Vertical-Heavy Duty (Cast Iron)
OH - Overhead Valve-Heavy Duty (Cast Iron)
The number designations following the letter indicates
the horsepower of the engine.
The number following the model number is the
specification number. The last three numbers of the
specification number indicate a variation to the basic
engine specification.
The serial number indicates the production data.
Using model number OH160-170033, Serial 8044C
as an example, interpretation is as follows:
OH160-170033 - is the model and specification number.
OH - Overhead Valve-Heavy Duty (Cast Iron)
160 - Indicates 16 horsepower.
170033 - is the specification number used for properly
identifying the parts of the engine.
8044C - is the serial number.
8 - first digit is the year of manufacture (1998)
044 - indicates calendar day of that year (044 day
or February 13, 1998).
C - represents the line, shift or plant in which the
engine was built at the factory.
1
SECTION 2. ENGINE CARE
FUELS. Use clean, fresh unleaded automotive gasoline
in all T ecumseh four-cycle engines. (Leaded “regular”
gasoline is an acceptable substitute.)
NOTE: Do Not use gasoline containing methanol
(wood alcohol). Gasoline containing a maximum of
10 ethanol or grain alcohol (sometimes called “gasohol”)
may be used but requires special care when engine
is unused for extended periods.
See “STORAGE” instructions.
ENGINE OIL, ALL FOUR CYCLE ENGINES:
USE A CLEAN, HIGH QUALITY, DETERGENT OIL.
Be sure original container is marked with engine
service classification “SF - SJ.”
DO NOT USE SAE10W40 OIL.
FOR SUMMER (ABOVE 32°F , 0°C) USE SAE 30 OIL
(SAE10W30 is an acceptable substitute.)
FOR WINTER (BELOW 32°F, 0°C) USE SAE 5W20
OR 5W30 OIL.
(SAE10W is an acceptable substitute.)
(BELOW 0°F , -18°C ONLY) Use 0W30 oil or SAE10W
oil diluted with 10% kerosene is acceptable.
CAUTION: Remove spark plug wire before doing
any service work on engine.
1. Service or replace air cleaner as necessary.
2. Inspect level and condition of oil; drain oil.
3. Remove blower housing, clean all dirt, grass or
debris from intake screen, head and cylinder cooling
fins and carburetor governor levers and linkage.
4. Remove cylinder head, remove carbon, inspect
valves and cylinder bore. Replace head using
a new head gasket. Torque to specifications.
5. Remove carburetor, clean and install carburetor
kit, make adjustment pre-sets where needed.
Make sure fuel tank, fuel filters and fuel lines
are clean. Reinstall carburetor, replacing any worn
or damaged governor springs or linkage. Make
proper governor adjustment.
6. Remove flywheel, check for leaks in oil seals,
check flywheel key and reinstall flywheel. Replace
spark plug and check for spark.
7. Make sure all remote linkage is properly adjusted
for proper operation.
NOTE: For severe, prolonged, winter operation of
HH120 model, SAE10W oil is recommended.
OIL CHANGE INTERV ALS. Change oil after first two
(2) hours of operation and every 25 hours thereafter,
or more often if operated under dusty or dirty conditions.
OIL CHECK. Check oil every 5 hours or each time
the equipment is used. Position equipment so the
engine is level when checking the oil.
BREAK-IN PROCEDURE. Proper break-in procedure
is important for proper seating of rings, on a new
engine or newly overhauled engine.
Do normal work with the unit, running the engine
under load. Vary the load on the engine frequently
to aid in seating of the rings.
The engine should not be allowed to idle or run at
part throttle for extended periods during break-in.
Work the engine but do not abuse it.
TUNE-UP PROCEDURE. The following is a minor
tune-up procedure. When this procedure is completed,
the engine will operate properly or you may discover
that further repairs may have to be performed.
NOTE: It is recommended to use only factory parts
in a Tecumseh engine. This is especially important
with an air filter, since the use of any other than the
specified part number may result in serious damage
to the engine.
8. Replace fuel and oil.
9. Run engine and adjust carburetor and set R.P .M.
to specifications found on Microfiche or computer
parts lookup.
STORAGE: (IF THE ENGINE IS TO BE UNUSED
FOR 30 DAYS OR MORE)
CAUTION: NEVER STORE THE ENGINE WITH
FUEL IN THE T ANK INDOORS , IN ENCLOSED
POORL Y VENTILA TED AREAS WHERE FUEL
FUMES MA Y REACH AN OPEN FLAME, SP ARK
OR PILOT LIGHT AS ON A FURNACE, WATER
HEA TER, CLOTHES DRYER OR OTHER GAS
APPLIANCE.
Gasoline can become unstable in less than 30 days
and form deposits that can impede proper fuel flow
and engine operation. T o prevent deposits from forming,
all gasoline must be removed from the fuel tank and
the carburetor. An acceptable alternative to removing
all gasoline is adding a fuel stabilizer to the gasoline.
Fuel stabilizer (such as T ecumseh’ s Part No. 730245)
is added to the fuel tank or storage container. Always
follow the mix ratio found on the stabilizer container.
Run the engine at least 10 minutes after adding the
stabilizer to allow it to reach the carburetor.
2
DRAINING THE FUEL SYSTEM:
CAUTION: DRAIN THE FUEL INTO AN
APPROVED CONT AINER OUTDOORS, AND
AWAY FROM ANY OPEN FLAME OR
COMBUSTION SOURCE. BE SURE THE
ENGINE IS COOL.
1. Remove all gasoline from the fuel tank by running
the engine until the engine stops, or by draining
the fuel tank by removing the fuel line at the
carburetor or fuel tank. Be careful not to damage
the fuel line, fittings, or fuel tank.
2. Drain the carburetor by pressing upward on the
bowl drain (if equipped) which is located on the
bottom of the carburetor bowl. On carburetors
without a bowl drain, the carburetor may be drained
by loosening the bowl nut on the bottom carburetor
one full turn. Allow to completely drain and retighten
the bowl nut being careful not to damage the
bowl gasket when tightening.
3. If "Gasohol" has been used, complete the above
procedure and then put one half pint of unleaded
gasoline into the fuel tank and repeat the above
procedure. If Gasohol is allowed to remain in
the fuel system during storage, the alcohol content
will cause rubber gaskets and seals to deteriorate.
Change Oil: If the oil has not been changed recently ,
this is a good time to do it.
Oil Cylinder Bore:
1. Disconnect the spark plug wire and ground the
wire to the engine. Remove the spark plug and
put 1/2 ounce (14 ml) of clean engine oil into
the spark plug hole.
2. Cover the spark plug hole with a shop towel.
3. Crank the engine over slowly several times.
CAUTION: A VOID SPRA Y FROM SP ARK PLUG
HOLE WHEN SLOWLY CRANKING ENGINE
OVER.
4. Install the spark plug and connect the spark plug
wire.
Clean Engine: Remove the blower housing and clean
all dirt, grass or debris from the intake screen, cylinder
head, cylinder cooling fins, carburetor, governor levers
and linkage.
3
CHAPTER 2. AIR CLEANERS, CARBURETORS,
GOVERNORS AND LINKAGE
SECTION 1. AIR CLEANERS
PAPER-TYPE AIR CLEANER SERVICE. Dry type
paper air cleaners are utilized on all T ecumseh Large
Frame engines. These air cleaners have treated paper
elements with rubberlike sealing edges. These edges
must seal properly to prevent dirt leakage.
COVER ELEMENT
SEALING EDGES
BASE
PAPER-TYPE AIR CLEANER SERVICE. Replace
air filter once a year or more often in extremely dusty
or dirty conditions.
DO NOT ATTEMPT TO CLEAN OR OIL FILTER.
Be sure to clean base and cover thoroughly before
installing new paper filter.
NEVER RUN THE ENGINE WITHOUT THE COMPLETE
AIR CLEANER INSTALLED ON THE ENGINE.
NOTE: Serious damage to the engine may result in
using other than the specified part number filter.
Use factory recommended parts only.
POLYURETHANE-TYPE AIR CLEANER. Some
T ecumseh Large Frame engines may use a polyurethane
air filter in conjunction with a paper filter.
GASKET
SPACER
BOLT
POLY
OUTER ELEMENT
FRONT COVER
BRACKET
BOLT
PAPER
ELEMENT
BACK
COVER
POLY-TYPE AIR CLEANER SERVICE. Clean and
re-oil every 3 months or every 25 operating hours,
whichever comes first. Clean daily if used in extremely
dusty or dirty conditions. Proceed as follows:
Remove wing nut and cover.
Slide foam filter off paper filter.
Wash foam filter in water and detergent solution and
squeeze, Don’t twist until all dirt is removed.
Rinse thoroughly in clear water.
Wrap in a clean cloth and squeeze, Don’t twist until
completely dry.
Saturate foam filter with engine oil and squeeze,
Don’t twist to distribute oil and remove excess oil.
Clean top side of base and inside of cover thoroughly .
Replace foam filter, cover and wing nut. T ighten wing
nut securely.
NEVER RUN ENGINE WITHOUT COMPLETE AIR
CLEANER INSTALLED ON ENGINE.
4
SECTION 2. GENERAL CARBURETOR INFORMATION
CARBURETOR IDENTIFICATION. Tecumseh
carburetors are identified by a model number and
code date stamping on the carburetor as illustrated.
ALTERNATE LOCATION
FOR MODEL NUMBER
89 3 F
89 3 F 5
This carburetor is used on the Overhead V alve engine
12, 14, 16 & 18 horsepower.
CARBURETOR
CODE DA TE
CARBURETOR
MODEL NUMBER
When servicing carburetors, use the engine model
number or the model number on the carburetor and
proper section in the Master Parts Manual or Microfiche
Catalog for proper service information.
CARBURETOR
MODEL NUMBER
FLOA T-FEED CARBURETORS. Float-feed carburetors
use a hollow metal float to maintain the operating
level of fuel in the carburetor. As the fuel is used,
the fuel level in the carburetor bowl drops and the
float moves downward. This actuates the inlet needle
valve, to allow fuel to flow by gravity into the fuel
bowl. As the fuel level in the bowl again rises, it
raises the float. This float motion adjusts the fuel
flow at the proper rate and keeps the fuel at the
proper mixture level.
These carburetors are used on some HH80-100120 and VH80-100 engines.
5
SECTION 3. TECUMSEH CARBURETORS
Following are initial carburetor adjustments to be
used to start the engine. After the engine has reached
operating temperature make final adjustments.
Main Adjustment HH80-100-120
Screw VH100, 1-3/4 turns.
Idle Adjustment HH80-100-120
Screw VH100, 1-1/4 turns
The Master Parts Manual or Microfiche has a direct
engine-to carburetor reference list. Further identification
of the carburetor is stamped on the carburetor body
as shown. Refer to the standard service part number
and the identification number on the carburetor body ,
in any correspondence.
CHOKE LEVER
THROTTLE
LEVER
NOTE: IDENTIFYING MARK WILL BE
THROTTLE
SHUTTER
FOUND IN THE 3 O’CLOCK POSITION
CHOKE. Examine the choke lever, shaft and shutter
prior to disassembly. Replace any worn parts.
1. Remove the screw in the center of the choke
shutter and pull out the choke shaft lever assembly .
2. When reassembling, replace the choke shutter
with identifying marks as positioned prior to
disassembly . Hold the choke shaft securely into
the bearing bore when replacing the choke shutter.
WELCH PLUG
CARBURETOR
MODEL NUMBER
CARBURETOR DISASSEMBL Y, INSPECTION AND
ASSEMBL Y . Carefully disassemble carburetor , removing
all non-metallic parts, i.e., gaskets, viton seats and
needles, “O” rings, fuel pump valve, etc.
THROTTLE. Examine the throttle lever shaft and
shutter prior to disassembly . Replace any worn parts.
1. Remove the screw in the center of the throttle
shutter and pull out the throttle shaft lever assembly .
2. When reassembling, replace the throttle shutter
with identifying marks as positioned prior to
disassembly. The throttle shaft must be held in
tight to the bottom bearing to prevent the throttle
shutter from riding on the throttle bore of the
body, causing excessive throttle shutter wear
and governor hunting.
CHOKE SHUTTER CUT
OUT CLEARANCE FOR
INTERNAL VENT TUBE
IDLE ADJUSTMENT SCREW. Remove the idle screw
from the carburetor body and examine the point for
damage to the seating surface of the taper. Replace
any damaged parts.
BAD
GOOD
6
HIGH SPEED ADJUSTMENT SCREW. For service,
examine the taper of the high speed adjustment screw.
If the taper is damaged at the area where it seats,
replace the screw and fuel bowl retainer nut as an
assembly.
FUEL BOWL RET AINING NUT. Remove the fuel bowl
retaining nut including fiber washer.
Examine the small fuel passage in the annular groove
in the retaining nut. This passage must be clean
for the proper transfer of fuel into the idle metering
system. Replace any worn parts.
When replacing, torque the fuel bowl nut to 50-60
inch pounds.
FUEL BOWL
FLAT OF FUEL BOWL
TOWARD FUEL INLET
FITTING
FIBER WASHER
TORQUE TO
50 - 60 INCH
POUNDS
FUEL BOWL
RETAINING NUT
“O” RING
BRASS WASHER
INLET NEEDLE. The inlet needle is anchored to
the float tab by a clip, to assure proper movement
of the inlet needle off of the seat when the float
drops. The inlet needle clip must be positioned as
shown during reassembly.
CLIP
OPEN END
LONG END
OF CLIP
CHOKE END
OF CLIP
THROTTLE END
Examine the inlet needle. If any wear is evident, or
any of the corners show signs of rounding, the needle
should be replaced.
The inlet needle hooks onto the float tab by means
of a spring clip. To prevent binding, the long, straight
end of the clip should face the choke end of the
carburetor as shown.
HIGH SPEED ADJUSTMENT
SPRING AND SCREW
FUEL BOWL. Check the bowl for corrosion or dirt.
Replace if necessary.
The fuel bowl must be free of dirt and corrosion.
When tearing down carburetor for repair, replace
fuel bowl “O” ring. Before installation lubricate the
“O” ring with a small amount of oil for easier installation.
The fuel bowl flat surface must be positioned on
the same side of the carburetor as the fuel inlet fitting
or same side as the float hinge pin to assure full
travel of the float.
“O” RING
CHECK FOR
CORROSION
AND DIRT
FUEL BOWL
FLOAT. Remove the float. Examine the float for crushing
or holes. Examine the float hinge bearing surfaces
through which the float hinge pin passes and replace
if worn.
SERVICING THE VITON SEAT.
a. REMOVAL. If the seat is to be replaced use the
bent end of a paper clip or wire with a 3/32'’
(.24 mm) hook. Push the hook through the Viton
seat hole. Then with the hook, pull the Viton seat
out. Replace with a new seat.
NOTE: A #4 crochet hook can also be used for removal.
b. INST ALLA TION.
NOTE: After thoroughly cleaning the cavity , moisten
the viton seat with oil.
Insert the seat with the grooved side into the
cup. Press the viton seat squarely into the base
with a punch.
3/32”
(.24 mm)
HOOK END
INST ALLATION OF VITON SEAT
INLET NEEDLE
SEATS AT THIS
POINT
REMOVAL OF VIT ON SEAT
INSERT THIS
FACE FIRST
7
HIGH SPEED NOZZLE. The carburetor body contains
a main nozzle emulsion tube pressed into the carburetor
body to a predetermined depth and positioned within
the venturi of the carburetor. Do not attempt to remove
this main nozzle. Repositioning of this nozzle will
seriously affect the metering characteristics of the
carburetor and will require replacement of the entire
carburetor.
CARBURETOR BODY. When removing the choke
and throttle shafts, check shafts and bearings in
carburetor body for wear. Any looseness in these
areas can cause dirt to enter the engine and cause
premature wear. If dust seals are present, these should
be positioned next to the carburetor body.
To do a proper cleaning job, welch plugs should be
removed to expose drilled passages. To remove the
welch plug, sharpen a small chisel to a sharp wedge
point. Drive the chisel into the welch plug, push down
on chisel and pry plug out of position.
MAIN NOZZLE
EMULSION TUBE
DO NOT REMOVE
WELCH PLUG
FUEL INLET FITTING. If necessary, this fitting can
be removed by pulling and twisting. Be sure to install
the fitting in the same position as the original. When
installing the fitting, insert tip into the carburetor
body, then coat the exposed portion of the shank
with Loctite grade A; then press it in until the shoulder
contacts the carburetor body.
PRESS IN P ARTIALLY
THEN APPLY LOCTITE
GRADE A
SOME INLET FITTINGS
UTILIZED A STRAINER
SMALL CHISEL
PRY OUT PLUG
DO NOT ALLOW
CHISEL POINT TO
STRIKE CARBURETOR
BODY
SMALL CHISEL
PIERCE PLUG WITH TIP
WELCH PLUG TO BE
REMOVED
ABOUT 1/8” (3.2 MM)
WIDE
When all accessories and shafts have been removed,
soak the carburetor in carburetor cleaner for a maximum
of 30 minutes. Blow out all passages with compressed
air in the opposite direction of normal fuel flow or
use a soft tag wire. Clean all metallic parts with solvent.
To install a new welch plug after cleaning, place
the welch plug into receptacle with raised portion
up. With a punch equal, or greater than the size of
the plug, merely flatten the plug. Do not dent or drive
the center of the plug below the top surface of the
carburetor.
FLAT-END PUNCH
NEW WELCH
PLUG
8
SAME OR LARGER
DIAMETER OF PLUG
FLOAT ADJUSTING PROCEDURE
All Tecumseh carburetors with an adjustable float
require the correct float height to achieve the proper
operation and easy engine starts. To check the float
setting, hold the carburetor in an upside down position.
Remove the bowl nut, float bowl, and "O" ring. Place
an 11/64" (4.369 mm) drill bit across the top of the
carburetor casting on the opposite side and parallel
to the float hinge pin. The float must just touch the
drill bit when the bit is flush with the edge of the
float. If the float is too high or too low, adjust the
height by bending the tab accordingly . If the required
adjustment is minor, the tab adjustment may be made
without removing the float and carefully inserting a
small bladed screwdriver to bend the tab.
FLOAT
FLOAT
SETTING
11/64” (4.369 mm)
ADJUSTING TAB
FLOAT HINGE
AND PIN
INLET NEEDLE
AND SEA T
9
SECTION 4. WALBRO CARBURETORS
HH80 - 120, VH80 - 100
WALBRO CARBURETORS. Following are initial
carburetor adjustments to be used to start the engine.
After the engine has reached operating temperature,
make final adjustments.
Main Adjustment HH80, 100, 120
Screw VH80, 100, 1-1/2 turns off seat
Idle Adjustment HH80, 100 120
Screw VH80 100 1-1/4 turns off seat
For proper carburetion the atmospheric vent MUST
be open. Examine and clean if necessary.
A sluggish engine speed control may at times be
caused by dirt or paint on the throttle return spring.
Clean if required.
Install the throttle plate with the numbers (if present)
facing out when closed. Move the throttle shaft to
the closed position, place the throttle plate on the
shaft and secure with the retaining screws. The throttle
should move freely. If binding is present, correct by
loosening screws and repositioning throttle plate.
THROTTLE LEVER
THROTTLE SHUTTER
THROTTLE STOP
SCREW
MOUNTING
FLANGE
62
29
INSTALL WITH
NUMBERS OUT
Examine the inlet needle. “A” is a needle that is
serviceable, if the tip appears damaged as “B”, replace
needle and seat assembly. Tighten the inlet seat to
40 to 50 inch pounds (4.5 - 5.7 Nm). Always use a
new gasket. Clean all dirt from the inlet seat cavity.
Choke lever positioning is maintained by the stop
spring, replace if damaged.
The fuel inlet fitting should be checked if leakage
is detected in the carburetor area. Do not screw in
too tight, this may crack the carburetor body. The
fuel bowl drain should also be examined in event
fuel leakage is detected. It may be necessary at
times to replace the internal rubber seat. Examine
the throttle return spring if slow engine response is
noted during operation. Correct by cleaning the throttle
return or realigning the throttle plate.
CHOKE STOP SPRING
THROTTLE LEVER
THROTTLE RETURN
CHOKE LEVER
FUEL INLET
FUEL BOWL
10
SPRING
SECONDARY
IDLE DISCHARGE
PRIMARY IDLE
DISCHARGE
THROTTLE SHUTTER
FUEL BOWL NUT
HIGH SPEED
ADJUSTMENT SCREW
Normally the main nozzle should not be removed.
It is possible to clean the carburetor with solvent
and compressed air. Remove and replace the main
nozzle only if the high speed needle seat is damaged
or because of excessive dirt.
“B” DAMAGED
- Replace
INLET
NEEDLE
“A”
INLET
SEAT
INLET SEAT
GASKET
INLET SEAT
CAVITY
MAIN NOZZLE
EMULSION TUBE
Do not remove the main nozzle. If it is necessary to
remove the main nozzle to aid in cleaning, discard
the main nozzle and use a service replacement nozzle
with an under cut in the thread area. If the nozzle
removed is under cut it can be reused. This procedure
must be followed to assure delivery of fuel to the
idle system.
UNDERCUT
ANNULAR
GROOVE
SERVICE
MAIN NOZZLE
(REUSABLE)
DO NOT REUSE IF REMOVED
ORIGINAL
MAIN NOZZLE
Float settings are measured opposite the float hinge.
Remove float by pulling out float axle. Bend adjusting
tab to correct setting. Always remove the float to
make adjustments.
Examine the float hinge and axle for wear. If evident
replace the parts.
FLOAT
SETTING
Ô
FLOAT
FLOAT HINGE
AND AXLE
Ô
ADJUSTING
TAB
INLET NEEDLE
AND SEAT
EARLY
NEW
This shows early and new needle valve, seat, gasket,
and spring assembly for large horsepower engine
carburetors.
Early carburetors have a metal-to-metal needle and
seat contact. The float setting for this model will be
.110'’ - .130'’ (2.794 - 3.362 mm).
New carburetors contain a viton seal in the seat and
a spring on the needle. For engines with the new
carburetor and having a fuel pump, the float setting
is .140 (3.556 mm).
For engines with the new carburetor, without a fuel
pump, the float setting is .075 (1.905 mm).
The float setting on carburetors used on vertical 8
and 10 H.P. engines is .070'’ to .110'’ (1.778 - 2.794
mm). No variance for carburetor having a fuel pump.
The gasket must fit over the float spring as shown
to avoid cutting by the spring when assembled.
GASKET GOES
OVER SPRING
(IF EQUIPPED)
CHOKE END OF
CARBURETOR
ENDS OF SPRING
POINT TOWARD CHOKE
END OF CARBURETOR
11
When assembling the float to the carburetor body,
position the needle spring on the adjusting tag so
that it hangs down. Hold the float spring under tension
until the carburetor body will support the slight spring
tension.
Prior to removing the fuel bowl nut, remove the high
speed adjustment needle. Use a 7/16'’ box end wrench
or socket to remove the fuel bowl nut. When replacing
the fuel bowl nut be sure to position the fiber gasket
under the nut and tighten securely.
NOTE: THE SPRING ENDS MUST POINT TOW ARD
THE CARBURETOR CHOKE END.
HOLD SLIGHT
SPRING TENSION
WITH THUMB
Ô
Position the choke shaft and shutter in the closed
position prior to tightening the screws. Hard starting
may be due to insufficient choking action because
of a misaligned choke plate. Correct by readjusting
choke plate to close completely.
A typical choke shutter found on horizontal engines
is shown in the figure below. The full choke position
of choke lever is counterclockwise when viewed from
top of the carburetor. Note cut-out position of choke
shutter.
INSTALL WITH
NUMBERS OUT
CCW
Examine the tip of the high speed needle, if it appears
as illustrated, replace. If the tip of the high speed
adjustment needle is damaged, the seat is probably
damaged. The seat is part of the main nozzle. When
replacing the high speed needle the main nozzle
should also be replaced.
HIGH SPEED
ADJUSTMENT NEEDLE
“O” RING
“B” DAMAGED
(Replace)
FUEL BOWL NUT
OUTSIDE GASKET
TENSION SPRING
FUEL BOWL
“A”
FUEL BOWL DRAIN
Use new gaskets when rebuilding the carburetor. If
the fuel bowl to carburetor body gasket does not
seat, enlarge by stretching with 4 or 5 quick short
strokes. Fiber gasket must be used between center
of fuel bowl and carburetor body.
CHOKE SHUTTER
62
29
AIR CLEANER
MOUNTING
Figure below shows a typical choke shutter found
on vertical engines. The full choke position of the
choke lever is clockwise when viewing from the top
of the carburetor. Note cut-out position of choke shutter .
CHOKE
SHUTTER
12
CW
AIR CLEANER
MOUNTING
NUMBERS
OPPOSITE SIDE
The fuel pick up passage must be clean to assure
adequate fuel flow from the fuel bowl to the metering
systems.
INSIDE FIBER
GASKET
FUEL
PICK-UP
PASSAGE
FUEL BOWL
GASKET AND SEAT
MAIN
NOZZLE
FLOAT
SECTION 5. OVERHEAD VALVE ENGINE CARBURETORS
Overhead valve engines utilize Walbro carburetors.
THROTTLE PLATE
THROTTLE
RETURN SPRING
IDLE SPEED
ADJUSTMENT
SCREW
IDLE
ADJUSTMENT
SCREW
FUEL BOWL
FUEL BOWL
RETAINING NUT
CHOKE LEVER
CHOKE
SHUTTER
ATMOSPHERIC
VENT OPENING
HIGH SPEED
ADJUSTMENT SCREW
CARBURETOR ADJUSTMENT. Carburetor factory
adjustment should not be changed. However, if required,
perform the following: with engine running (Allow
engine to warm up for 5 minutes). Open throttle (speed
control at “RUN” or “FAST” position). Adjust high
speed adjustment screw per chart, clockwise or
counterclockwise until engine runs smoothly. With
control in idle or slow position, adjust idle speed
adjustment screw to obtain correct idle speed. If
necessary , readjust idle adjustment screw clockwise
or counterclockwise until engine idles smoothly.
CARBURETOR SERVICING
Throttle Shutter
Install the throttle shutter with the numbers facing
out when closed. Move the throttle shaft to the closed
position, place the throttle shutter on the shaft and
secure with new retaining screws. The throttle should
move freely . If binding is present, correct by loosening
screws and repositioning throttle shutter.
THROTTLE PLATE
INSTALL WITH
NUMBERS OUT
MOUNTING
FLANGE
IDLE SPEED
ADJUSTMENT
SCREW
RETAINING
SCREWS
THROTTLE
SHUTTER
CHOKE SHUTTER. Position the choke shaft and
shutter in the closed position to tighten the screws.
Hard starting may be due to misaligned choke plate.
Correct by readjusting the plate to close completely .
INSTALL WITH
NUMBERS OUT
CHOKE SHAFT
HIGH SPEED
CARB. ADJ. SCREW* IDLE ADJ. SCREW*
OH120
THRU 1 TURN* 1 TURN*
OH180
*All Adjustments Off of Seat
IDLE ADJUSTMENT SCREW. Close idle adjustment
screw by turning clockwise. Close finger tight only.
Forcing will damage screw.
OPEN IDLE ADJUSTMENT SCREW: 1 turn
counterclockwise.
Start engine and with the throttle open (then return
to idle position), adjust idle adjust screw one-eighth
(1/8) turn at a time clockwise or counterclockwise
until engine runs smoothly.
With control at “idle” or “slow” position, adjust idle
speed adjustment screw to obtain correct idle speed.
If necessary, readjust idle adjustment screw until
engine idles smoothly.
CHOKE
SHUTTER
ATMOSPHERIC
VENT
AIR CLEANING
MOUNTING
HIGH SPEED ADJUSTING SCREW. Prior to removing
the fuel bowl nut, remove the high speed adjusting
needle. When replacing the fuel bowl nut be sure
to position a fiber gasket on each side of the fuel
bowl.
13
Examine the tip of the high speed adjustment screw.
If the tip of the screw is damaged, the seat, which
is part of the main nozzle, is probably damaged.
When replacing the screw, the nozzle should also
be replaced with a service replacement nozzle only .
HIGH SPEED
ADJUSTMENT SCREW
FUEL BOWL
TENSION
SPRING
INLET NEEDLE & SEAT. The inlet needle and seat
are replaceable as an assembly. If the tip appears
damaged, replace the needle and seat assembly.
MAIN NOZZLE
“O” RING
“B” DAMAGED
Replace
FUEL BOWL NUT
OUTSIDE FIBER
GASKET
MAIN NOZZLE. Normally the main nozzle should
not be removed, if it is, clean the carburetor with
solvent and compressed air. Remove and replace
the main nozzle only if the seat is damaged or is
excessively dirty.
If it is necessary to remove the main nozzle, discard
it and use a service replacement nozzle with an undercut
in the thread area. If the nozzle removed is already
under cut, it can be reused. This replacement assures
delivery of fuel to the idle system.
“A”
RE-USE
INSERT
FACE FIRST
INLET SEAT
CAVITY
FLOA T
MOUNTING
INLET NEEDLE TIP
SEATS AT THIS POINT
“B” DAMAGED
Replace
CHAMFERED
EDGE
FLOA T SETTING. Float Settings are measured opposite
the float hinge. Remove float by pulling out float
axle. Bend adjusting tab to correct setting. Always
remove the float to make adjustments.
Replace the float and axle if wear is evident. The
float must measure .275” / .315'’ (6.985 / 8.001 mm)
from top of boss to surface of float (closest to center).
MEASURE AT EDGE
CLOSEST TO CENTER
Ô
Ô
.275 (6.985 mm)
.315 (8.001 mm)
FLOAT HINGE
AND AXLE
UNDERCUT
ANNULAR
GROOVE
SERVICE MAIN
NOZZLE - REUSABLE
ORIGINAL
MAIN NOZZLE
(DO NOT REUSE IF REMOVED)
FLOAT
ADJUSTING TAB
INLET NEEDLE
AND SEA T
Position carburetor in an upright position.
If float is lower than dimensions shown in figure,
bend outside tab GENTLY so float does not drop
plus or minus .060'’ (1.524 mm) from base of boss.
FLOA T
OUTSIDE TAB
BOSS
.060
(1.524 mm)
14
ASSEMBLING SEA T , SPRING & FLOA T. Shown below
is the float, hinge pin, seat and the float spring.
DAMPER
SPRING
PIN
FLOA T
When assembling the float to the carburetor body,
position the needle spring on the adjusting tang so
that it hangs down. Hold the float damper spring
under tension until the carburetor body will support
the slight spring tension. The spring ends must point
toward the carburetor choke end.
FIXED HIGH SPEED CARBURETOR. On carburetors
of a later design the high speed screw has been
replaced by a fixed speed nut. Adjustment is made
only on the idle adjustment screw since the high
speed setting is fixed.
HOLD SLIGHT SPRING
TENSION WITH THUMB
The bowl gasket must be positioned over the float
spring as shown.
FUEL BOWL GASKET AND SEAT
FUEL
PICK-UP
PASSAGE
INSIDE FIBER
GASKET
IDLE ADJUSTMENT
SCREW
FIXED SPEED NUT
WALBRO WHG. The early production OH engine
was equipped with a LMH carburetor. The newer
engines since 1987 have been manufactured with
a WHG carburetor. Service replacements are all WHG,
which include an instruction sheet covering service.
WHG
LMH
GASKET GOES
OVER SPRING
FLOAT
WHG LMH
NEW WHG
EARLY LMH
15
SECTION 6. GOVERNORS
This Governor Assembly is used on current production
HH & OH Tecumseh Engines.
SHAFT PRESSED TO GEAR
GOVERNOR GEAR
WASHERS
To position the governor gear assembly, insert the
shaft opposite the flyweights into the cylinder block.
SPOOL
There is an oil groove on the inside of the spool to
prevent oil pressure from building up under the spool.
Position the governor gear and flyweight assembly
on the governor gear shaft. Secure with a retaining
ring. Place the governor spool on the governor gear
shaft.
The spool is positioned on the governor gear shaft
with the fingers of the flyweight under the rim of the
spool.
Some models have an oil hole in the closed end for
lubrication. CAUTION: On reassembly make sure
hole is open. Other models have a groove on the
inside that serves the same purpose.
PRESS GOVERNOR
“GEAR SHAFT’
INTO THIS DIMENSION*
1” (25.4 mm)
GOVERNOR
GEAR
FLYWEIGHT
ASSEMBLY
WASHER
Position the governor gear assembly (with washer
under governor gear) to mesh with the camshaft gear.
Place the governor spool (with washer under the
spool) on the governor gear assembly, with the fingers
of the flyweights under the rim of the spool.
GOVERNOR SPOOL
GOVERNOR SHAFT
GROOVED SLOT
(INTERNAL)
GOVERNOR GEAR
FLYWEIGHT
*1.031” (26.187 mm)
RETAINING RING GROOVE
OIL HOLE
(ON SOME MODELS)
GOVERNOR
GEAR SHAFT
GOVERNOR GEAR AND
FLYWEIGHT ASSEMBLY
ON MODELS WITH WASHER
WASHER ON
SOME MODELS
RETAINING RING
Remove the governor gear shaft by threading the
shaft with 1/4-28 die. Place a number of washers
on the shaft and turn on a nut. By tightening the nut
against the washers the shaft will be pulled from
the cylinder.
For old style governor assembly , position the governor
gear shaft over the opening in the cylinder block
and tap lightly with a hammer to start. Use a press
to position. Refer to top picture for proper pressed
in depth. Measure from the top of the governor gear
shaft to the machined surface on the cylinder block.
16
GOVERNOR ROD
CYLINDER COVER
GOVERNOR ADJUSTMENT FOR HORIZONTAL ENGINES
RETAINING RING
GOVERNOR SPOOL
CONTACTS LEVER
The governor rod is retained in the cylinder cover
bushing with a retaining ring.
The governor spool moves the governor rod by
contacting the lever. Outward movement of the governor
spool moves the governor levers and carburetor throttle
to a closed position.
The lever must contact the governor spool tightly
for best governor control and for correct adjustment
procedure.
BEARING WITH
SEAL TO OUTSIDE
BEARINGS
RETAINING RING
WASHER
BEARING END
FLUSH WITH CASTING
The governor rod on some valve-in-head model engines
utilize needle bearings. If bearing(s) are removed,
always install new bearing(s). Remove with 3/8'’
(9.525 mm) diameter punch and mallet. To install,
tap the first bearing in until the bearing end is flush
with casting. Holding a finger over hole will indicate
when bearing is driven into casting far enough. Drive
the outside bearing in with edge flush with outside
surface of casting and seal (in bearing) at outside
end.
GOVERNOR ADJUSTMENT FOR HORIZONTAL
ENGINES (See Picture: Governor Adjustment for
Horizontal Engines)
Move remote controls to RUN position.
Loosen Screw “A”.
Pivot plate “B” counterclockwise (ccw) and hold.
Move lever “C” to left.
“C”
“A”
“B”
TURN CCW
GOVERNOR
ADJUSTING
SCREWS
PIVOT POINT
GOVERNOR
SPRING
MOVE TO
‘RUN’ POSITION
1. SETTING VARIABLE SPEED ADJUSTING
SCREW. Before attaching the bowden wire, set
the engine for maximum R.P.M. (See Mfg.
specifications) with engine running. Use a good
tachometer. Move lever “A” clockwise until lower
end strikes the adjusting screw at “1”. (See picture
below)
Loosen lock nut on adjusting screw and turn in to
decrease R.P.M. Turn out to increase R.P.M.
CAUTION: DO NOT EXCEED RECOMMENDED R.P .M.
2. ADJUSTING FIXED SPEED. The fixed speed
adjusting screw is the optional position “2”. Adjust
it by starting the engine, then loosening the locknut.
Turn screw in to increase R.P.M. and out to decrease
R.P.M.
IDLE
(CW)
ADJUSTING SCREW
FIXED SPEED
POSITION “2”
OPTIONAL
ADJUSTING SCREW VARIABLE
SPEED POSITION “1” STANDARD
FAST
HOLE “B”
“A” LEVER
PIVOT
BOWDEN WIRE
CLAMP “B”
HOLE “C”
(CW)
BOWDEN WIRE
CLAMP “C”
Tighten screw “A” securely.
When the governor is properly set, the carburetor
throttle lever will be in a wide open position when
the controls are set for starting.
The governor spring is to be anchored in the bottom
center hole (D) of plate “B”. Do not stretch or cut
the governor spring. Above adjustments will correct
any variations in governor control.
17
VERTICAL CRANKSHAFT GOVERNOR
ADJUSTMENT.
Move remote controls to RUN position.
Loosen screw “A”.
Turn plate “B” counterclockwise (ccw) and hold.
Move lever “C” to left.
Tighten screw “A” securely.
When the governor is set properly the carburetor
throttle will be in wide open position.
GOVERNOR ADJUSTMENT VERTICAL
Ô
THROTTLE TOWARD
FULL OPEN
THROTTLE TOWARD
FULL CLOSED
Ô
ADJUSTING FIXED SPEED. The fixed speed adjusting
screw is the optional position “2”. Adjust it merely
by starting the engine and after loosening the lock
nut turn screw in (clockwise) to increase spring tension
and hold engine at higher R.P.M. and out
(counterclockwise) to decrease tension on spring
and allow speed to be decreased more easily.
“FIXED SPEED”
BOWDEN WIRE
CLAMP “B”
HOLE “B”
HOLE “C”
BOWDEN
WIRE
CLAMP “C”
GOVERNOR
SPRING
LEVER “C”
SCREW “A”
“D”
PLATE “B”
TURN CCW
GOVERNOR
ADJUSTING
SCREWS
V ARIABLE SPEED ADJUSTMENT. Before attaching
the remote speed control (bowden wire) set the engine
for maximum R.P.M. (See Mfg. specifications). Use
a good tachometer.
Move lever “A” clockwise until lower end strikes the
adjusting screw “1”.
Loosen lock nut on adjusting screw “1” and turn in
(clockwise) to decrease R.P .M. and out counterclockwise
to increase R.P.M.
ADJUSTING SCREW
FIXED SPEED
POSITION “2”
(OPTIONAL)
“A” LEVER
ADJUSTING SCREW
VARIABLE SPEED
POSITION “1”
(STANDARD)
CAUTION: DO NOT EXCEED RECOMMENDED R.P .M.
18
SECTION 7. IMPULSE FUEL PUMP
IMPULSE FUEL PUMP. This pump is mounted onto
the carburetor inlet and has connections from the
fuel supply and also a pulse line to the engine crankcase.
CAUTION: IN ORDER FOR THE PUMP TO OPERA TE
SATISFACTORILY THE CORRECT OIL LEVEL IN
THE CRANKCASE MUST BE MAINTAINED. TOO
MUCH OIL WILL ADVERSEL Y EFFECT THE PUMPS
OPERATION.
It is operated by changing pressure created by the
engine piston movement and transmitted to the pump
through a pulse line. The increasing and decreasing
pressures acting on the diaphragm and flap valves
lift fuel from the fuel tank to the carburetor of the
engine.
CARBURETOR FITTING
VALVE OPEN
ATMOSPHERIC
VENT
FUEL SUPPLY
±
CRANKCASE PRESSURE CRANKCASE SUCTION AND Ü SUCTION FUEL FLOW
Ô ATMOSPHERIC PRESSURE Ô ATMOSPHERIC PRESSURE Ô ATMOSPHERIC PRESSURE
ACTING ON DAMPING ACTING ON DAMPING CAUSED FUEL FLOW
DIAPHRAGM DIAPHRAGM
ÜFUEL FLOW
DIAPHRAGM
FILTER
AIR BLEED
VALVE CLOSED
PULSE LINE
TO CRANKCASE
±
FLOW DIRECTION DIRECTION
VALVE
CLOSED
VALVE
OPEN
FOUR SCREWS INTO
BACKSIDE OF PLATE
TO BACKSIDE
OF PLATE
WHEN ASSEMBLED
THIS SIDE FACES INTO
CONCAVE CAVITY OF
ABOVE ASSEMBLY
SPRING IN
HOLE CAVITY
BUTTON WITH SPRING
TYPE I
To service, separate the pump by removing the four
(4) screws. Clean all new parts with a solvent and
install a new kit which consists of coil springs, gaskets
and diaphragms.
The diaphragms must be installed against the center
body with the gaskets against the outside covers.
The parts are designed so they cannot be misassembled
without damage.
T o test the unit, assemble the carburetor to the engine,
leaving the pump off. Connect gravity fuel feed supply
to the carburetor. With the pulse line connected to
the pump and engine running, a definite flow should
result.
If the flow is erratic or intermittent, the pump needs
repair or replacement.
PREVIOUS STYLE
TYPE I
NEW STYLE
TYPE II
The new style pump (TYPE II) will replace older (TYPE
I) pumps. An assembly kit is available with instructions
and all the parts needed to convert to the new style.
If a complete replacement of an old style is not necessary ,
a repair kit is still available.
19
CHAPTER 3. REWIND STARTERS, ELECTRIC STARTERS,
TROUBLESHOOTING AND GENERATORS
SECTION 1. REWIND STARTERS
REWIND ST ARTER DISASSEMBLY PROCEDURE
1. Clamp starter in a vise and pull rope out, and
clamp pulley.
2. Untie knot in rope and remove.
3. Slowly release spring tension.
4. Remove retainer screw, retainer cup; starter dog
and spring, and brake spring.
5. Lift out pulley, turn spring and keeper assembly
to remove from housing.
Replace all worn or damaged parts.
BRAKE SPRING
RET AINER
WASHER
RETAINER
RETURN
SPRING
PULLEY
STAR TER
DOGS
SPRING REPLACEMENT. Disassemble the starter
completely.
New springs are enclosed in retainers. Be sure spring
is positioned with wrapping in direction as illustrated.
Position new spring and retainer over housing and
press the spring out of the retainer into the starter
housing.
APPLY LIGHT
LUBRICANT
REWIND
SPRING
REASSEMBLY. Lubricate the recoil spring and center
shaft with a small amount of light grease. Place the
pulley over the center shaft and bottom. Insert a
1/8'’ (3.175 mm) punch or rod into the through hole
in the pulley, and turn the pulley. This will aid in
positioning and engaging the spring.
1/8” (3.175 mm)
PUNCH
TURN PULLEY
INSERT PUNCH INTO
THROUGH HOLE AIDING
SPRING ENGAGEMENT
REWINDING SPRING AND REASSEMBLY. Place
the large washer, 1-3/8'’ (34.925 mm) over the center
shaft. Insert the dogs, so that they will fold in close
to the center. Press the brake spring on the retainer.
The brake spring must be a tight fit on the retainer.
Hold the retainer and brake spring assembly at an
angle to engage the return spring to the dowel on
the pulley. Secure with the center screw and washer
and tighten securely . Failure of the starter to engage
may be traced to either a loose center screw, or
loose brake spring. Tighten the screw or replace
the brake spring. Replace the rope as outlined.
20
VISE
SCREW DRIVER
PREWIND
7 TURNS
INSERT ROPE
CLAMP WITH PLIERS TO
RETAIN TENSION
ROPE REPLACEMENT. Prepare the rope, place a
thin 3/4'’ (19.05 mm) diameter washer with a 1/4'’
(3.175 mm) hole on the rope and tie a knot. The
other end of the rope should be thinned to a point
for easier threading.
Clamp the starter in a vise, upside down, by one
leg opposite the rope outlet. Place a screw driver
in the rope hole of the pulley and turn counterclockwise
until tight, then allow to unwind until hole in pulley
for rope lines up with hole in housing. Clamp the
pulley in this position with lever action pliers. Clamp
over starter housing and pulley, protect the painted
surface.
Insert the rope into the pulley hole and guide it with
needle nose pliers through the rope outlet in the
housing. Secure the handle with a double knot. Hold
the rope taut, release the pliers and allow the rope
to wind on the pulley.
ASSEMBLING ST ARTER TO ENGINE. It is important
to center the starter hub containing the starter dogs
in the center cup so there is equal contact on all
the dogs into the teeth of the cup.
Before securing the starter with the mounting screws,
place the hub into the cup then pull the rope enough
to cause the starter dogs to equally engage in the
teeth. With the dogs securely in the cup, tighten
the mounting screws to 40-60 inch pounds
(4.5 - 6.8 Nm) torque. If mounting holes do not line
up, blower housing is bent and must be replaced.
TIGHTEN STAR TER MOUNTING SCREWS AFTER HUB
IS CENTERED IN CUP
ST ARTER
CUP
STAR TER DOGS EQUALLY SECURE IN TEETH FOR
CORRECT CENTERING OF STAR TER HUB
ST ARTER
HUB
ST ARTER
ON SOME VALVE-IN-HEAD ENGINES:
PULLEY (SHEAVE-TYPE) STARTER. Consists of
a rope sheave-type. The engine comes equipped
with starter rails and the blower housing is constructed
with a removable plate for conversion to an electric
start.
STARTER DOG
WASHER
CENTER SCREW
21
SECTION 2. ELECTRIC STARTERS
STARTER SERVICE, DISASSEMBLY AND
INSPECTION. Part No. is found on identification tag.
Used on large frame vertical and horizontal engines.
PAR T NO.
Repair of these starters consists of replacement of
parts shown in the exploded view.
1. Testing
T est 12 V olt starters under the following conditions:
a. Conduct test with fully charged battery.
b. Engine and oil temperature approximately
70° F (21°C).
c. Engine contains recommended oil.
d. Cranking test not to exceed 10 seconds.
e. Parasitic loads removed from engine.
MODEL AMPERES ENGINE RPM
33835 70 MAX. 600 MIN.
HOUSING & ARMATURE NOT AVAILABLE
ORDER COMPLETE SYSTEM
T est and trouble shooting procedures for 12 volt starters
can be found in other Sections of this chapter.
2. Disassembly.
a. Remove two (2) lock nuts from thru bolts on
drive end of starter.
b. Grasp drive end of starter and remove from
housing as an assembly.
HOUSING
LOCK NUTS (2)
THRUST
WASHER
DRIVE END
c. Remove dust cover, retaining ring, spring
retainer, anti-drift spring, gear and engaging
nut. Remove drive end cap from armature.
ENGAGING NUT
SPRING
RET AINING
RING
DUST COVER
LOCK NUTS (2)
GEAR
SPRING RET AINER
ARMATURE
THRUST
WASHER
THRUST WASHER
DRIVE END CAP
22
d. T o remove end cap assembly, loosen the nut
on terminal post. Remove the lock nuts and
thru bolts from starter housing. Remove brushes
or brush card separately or as an assembly .
NOTE: Care must be taken in removing and
reinstalling brush springs to eliminate damage
to spring and malfunction of brushes.
3. Inspection
Inspect, clean and replace parts if necessary.
Test motor parts for open and shorted circuits.
Loading...