Tecumseh SPECTRA 37 Installation and operating manual

2
BH 37 E-45040E SER 5 174 C
A. FOREWORD
This manual contains information required to service or
repair all Tecumseh Italian built engines.
For exploded views of particular engines or component
part numbers, refer to the Tecnamotor and Tecumseh
Europa Spare Parts Catalogue.
When ordering spares from your authorized Tecumseh
Dealer, please quote the entire model and specification
number. These numbers are stamped on the engine as
shown below.
Always insist on genuine Tecumseh replacement parts.
ENGINE CODE
SPECTRA37 E-38000 SER 5 174 A
MODELLO
SPECIFICA
NUMERODISERIE
ANNO DI COSTR.
GIORNO DI COSTR.
TURNO
BH 37 E-45040E SER 5 074 C
MODELLO
SPECIFICA
NUMERO DI SERIE
ANNO DI COSTR.
GIORNO DI COSTR.
TURNO
MV 100 S E-16000C SER 5 074 C
MODELLO
SPECIFICA
NUMERO DI SERIE
ANNO DI COSTR.
GIORNO DI COSTR.
TURNO
SPECTRA 37 E-38000 SER 5 174 A
MV 100 S E-16000C SER 5 174 C
S
S
S
S
S
S
174
174
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SERVICE BULLETIN
Subject: 2-stroke engines - running in and oil requirements
Tecumseh now requires that all 2-stroke engines with a recommended fuel/oil mix
greater than 25 : 1 should be run with the first tank of fuel mixed at double the
recommended ratio. This gives increased protection during the piston ring seating
process.
We also highly recommend the use of Tecumseh smokeless oil (part number
26980003),which isan extremelyhigh qualityand environmentallyfriendly product.
Theuseofalternativeoilswhich maybeof alowerqualitywill invalidatethewarranty.
70/A
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Fig. 1
B. CHECK-UP BEFORE REPAIR
1. GENERAL
If a customer complains of an engine “non-starting”, it is
a good rule to make an accurate check by first pulling
thestartertoensure thatthere areno internalbreakages.
Ascertain that the correct fuel/oil mixture is being used.
(2-stroke engines).
Check the carburettor and governor controls, remote
control,aircleaner,sparkplug,oil level(4-strokeengines).
Drain and refill fuel tank with fresh, clean fuel.
For 2-stroke engines, AV and MV, use a 4% (25:1) or
2%(50:1)petrol/oilmixture.Refer totheoperator'smanual
for correct mix for each engine.
USE CLEAN FRESH FUEL FOR TESTING
NOTE - If engine is fitted with remote control and choke,
check that:
- With the lever in the choke or start position, the choke
is fully closed and the throttle open. This is important
for starting from cold.
- With the lever in the max position, make sure that the
throttle is fully open. If full throttle is not being attained,
maximum power will not be obtained from the engine.
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2. RECOIL STARTER (CHOKE)
a - Move controllever (Fig2) onengine orremote control
(Fig 2) on equipment to choke or start.
b -Operate mower control to release engine brake (if
any).
c - Pull starter handle (Fig 2-2) with a quick firm action.
Allow the rope to recoil back into its housing whilst
retaining grip on handle.
d -Repeat preceding instructions B and C until engine
starts.Then graduallymove controllever onengine or
remotecontrol onequipment awayfromchoke orstart
tomax position.
NOTE - If engine fires, but fails to start, move control
lever on engine or remote control on equipment to MAX
position and repeat preceding instructions B and C until
engine starts.
NOTE - Warm engine normally starts without choking.
Move control lever (Fig 2) on engine or remote control
(Fig 2) on equipment to MAX position; then follow ‘b’ ‘c’
and ‘d’ instructions.
RECOIL STARTER (PRIMER)
a -Move control lever (Fig 2-1) to “FAST” or “START”
(see equipment manufacturer’s instructions).
b -Push primer (Fig 2-1) three (3) times. Wait about two
(2)secondsbetweeneach push.Incold weather(55F/
13°C or below) push five (5) times.
NOTE - Do not use primer to restart a warm engine
c - Operate mower control to release engine brake (if
any).
d - Grasp starter handle (Fig2-2) andslowly pull ropeout
until a slight resistance is felt. Let rope rewind slowly.
Then pull rope with a rapid full arm stroke.
NOTA - If engine fails to start after three (3) pulls, repeat
instructions ‘b’, ‘c’ and ‘d’.
Fig. 2
Fig.2-1
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RECOILSTARTER(PRIMER FIXED SPEED)
a -Push primer (Fig 2.1) three (3) times. Wait about two
(2) seconds between each push. In cold weather
(55°F/13°C or below) push five (5) times.
NOTE - Do not use primer to restart a warm engine.
b - Operate mower controlto release engine brake.
c - Grasp starter handle (Fig 3) and slowly pull rope out
until a slight resistance is felt. Let rope rewind slowly.
Then pull rope with a rapid full arm stroke.
NOTE - If engine fails to start after three (3) pulls, repeat
instructions ‘a’,’b’ and ‘c’.
If the engine starts and runs satisfactorily, the customer
should be instructed on starting and maintenance
procedure, otherwise continue engine fault check.
ELECTRIC STARTER ( Fig 2-2)
Tostart enginewith electric startoption, follow theabove
procedureexceptuse thekeytoactivate thestartermotor.
NOTE - Ensure engine has stopped rotating before re-
engaging the starter motor.
3. CHECK-UP
A general systematic check can usually locate the fault
ina matterof minutes.The followingfive pointscoverthis
operation:
- Starter
- Compression
- Ignition
- Carburetion
- Equipment
a) STARTER
Pull starter and ensure that the starter dog engages and
turns the engine. If not, see chapter C, Starter Repair
Methods, ensure that the rope has not been shortened,
thus reducing the number of starting revolutions. The
compression may also be checked by this operation.
Fig.2-2
Fig. 3
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b) COMPRESSION
If compression is poor, check for:
- Flywheelslipping on crankshaft.
- Loosespark plug.
- Loose cylinder head bolts.
- Damaged cylinder head.
- Warped cylinder head.
- Insufficient tappet clearance (4-stroke engines).
- Broken connecting rod.
- Loose or worn crankshaft seals (2-stroke).
Ifengineis fittedwithcompression release,itis necessary
to remove cylinder head and check components visually
if a leak tester is not available.
NOTE - With the compression leak tester faults can be
found easily within minutes (Fig 4).
c) IGNITION
Remove spark plug and connect a new one to the HT
lead, earth plug body to cylinder head, turn the engine
and check that a strong spark occurs between the plug
electrodes. If no spark occurs see chapter Efor service
and repair instructions.
If spark occurs, fit new spark plug and attempt to start
engine. Remember that spark failure can also be due to
such faults as:
- Broken flywheel key.
- Crankshaft bearing worn, thus preventing cam from
opening (breaker point ignition).
- Incorrect air gap setting (electronic ignition).
NOTE - When using the compression leak tester
( Fig 4) and the ignition tester (Fig 5), faults may quickly
be located. If no fault can be found, the defect must be
within the carburation system or the equipment.
Fig. 4
Compression Leak Tester. Tests for leakage of valves,
rings and cylinder head in situ.
Fig. 5
Tests standard ignition system in situ. Solid state units
mustbe removed fortest.
d) CARBURATION
Afterhavingdrainedandcleaned fueltank,refill withfresh
fueland check(float carburettors) thatfuel flowsfrom the
bowlwhen the drainvalve ispressed.
On diaphragm carburettors without primer, remove high
speed jet and operate diaphragm. Fuel should then flow
fromjet seat.
If fuel does not flow, check fuel line and filters, re-set
carburettor as in chapter Gand carry out starting
procedure.
Ifengine stillfailsto start,remove sparkingplug and pour
asmall quantity offuel into thecylinder, replacesparking
plug and attempt to start. If engine fires a few times it
may be assumed that the carburettor is at fault. Check
completely the carburettor as in chapter G.
Fig. 4
Fig. 5
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NOTE - On 2-stroke engines a broken or damaged reed
plate will prevent starting.
e) EQUIPMENT
What may initially appear to be an engine fault, such as
a starting difficulty or engine vibration, may possibly be
the fault of the equipment rather than the engine.
Owing to the great number of machines in use, it is not
possible to list these separately. The following is a list of
themore commonproblems:
Hard Starting, Kickback, Failure to Start
- Looseblade.Theblademustbetightonshaftoradaptor.
- Loose belt. A loose belt, as with a loose blade, can
causeabacklash effectwhichwillcounteract theengine
cranking effort.
- Starting under load; ascertain that the equipment is
disengaged if the unit has a heavy starting load.
- Check remote control assy for proper adjustment with
the lever Ain choke or start position. The carburettor
choke should be fully closed (Fig 6).
- Grass cuttings building up under deck may cause
difficulties. Clean deck.
- Check that grass collectors are empty. An overfilled
collector could cause engine malfunction.
Vibration
- Damaged or out of balance blade
- Damaged or out of balance impellor
- Loosemounting bolts, engineto deck
- Wornblade mounting;replace ifmounting allowsblade
tomove causingunbalance.
Noise
- Cutter blade coupling or pulley, an oversize or worn
coupling can result in knocking, particularly under
acceleration. Check for fit and tightness.
Fig. 6
A
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C. STARTER
NON-STYLIZEDSTARTERS
LAV - BV - BVS - VANTAGE - HBL - BH - AV -
MV
1. RECOILSTARTER
In the event of starter failure, remove the unit from the
engine and check the following items:
- That dog A(Fig 1) protrudes when the rope is slowly
pulled. If the rope cannot be pulled, check the retainer
hublocking screwBforcorrecttighteningtorque,which
should be kgm 0.5 - 0.6 (45/55 inch lbs).
- If, after correct tensioning of screw B(Fig 1), the dog
does not function, disassemble the starter as follows,
referring to exploded view shown in Fig 2.
Fig 2 - Exploded View Standard Top Starter
1. RetainingScrew
2. Retainer
3. BrakeSpring
4. Dog
5. DogReturnSpring
6. RopePulley
7. RewindSpring
8. StarterHousing
9. Rope
10. Handle
To disassemble starter
Release spring tension. Slightly extend rope and lock
pulley . Untie knot or remove staple securing handle and
release pulley (Fig 3).
- Removecentre locking screw.
- Remove retainer hub, brake spring and dog.
- RemovedogreturnspringB,bearinginminditsposition
for correct replacement. (Fig 6).
- Removepulley and springcontainer assembly.
- Oncethe damagedparts havebeenreplaced, lubricate
spring container with soft grease (Fig 4) and proceed
withreassembly.
Fig. 1
Fig. 4
Fig. 2
Fig. 3
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To reassemble starter
- Accurately position spring container on pulley (Fig 5).
- Repositionthepulleyassembly intocontainerlubricating
shaft and bushing of plastic pulley.
Fig.5
A. Spring Engagement
B. Spring Disengagement
- Refit retainer spring, place dog and brake spring in
position (Fig 6).
- Accurately position retainer hub and secure with the
screw.
- Re-tension recoil spring.
- Wind pulley clockwise until tight, then allow to unwind
untilthe hole inthe pulley linesup withthe eyelet inthe
housing. Lock pulley. Install rope and handle. Tie knot
in rope to secure to pulley. Release pulley. (Fig 3).
- After reassembling starter, always make sure that by
pulling the rope slightly the starter dog operates, and
that the rope can be fully extended. When released,
the handle should be held firmly against the starter
housing.
- The correct tension of the spring is obtained after
approximately 5 turns of the pulley.
2. SIDE MOUNTED STARTER HORIZONTAL
ENGAGEMENT TYPE (LAV, BV)
The side mounted starter was developed for use on
machinesin whichenginesare mountedin alow position.
(Fig 7).
Fig 8 - System of Engagement
A. Flywheel gear
B. Pulley gear
The starter operates the engine by engaging a gear into
teeth on the underside of flywheel. (Fig 8). When the
engine starts, the flywheel speed disengages the starter
gear.
Fig. 5
Fig. 6
Fig. 7
Fig. 8
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Disassembly
Disassemble starter as follows. Refer to Fig 9.
- Releasemainspring tension(5)byremovingthe handle
and sliding the rope (12) out of the rope clip (16).
(Fig 10).
- Remove rope clip and replace if necessary.
- Remove the two screws (1) and spring cover (2). The
spring (5) may be replaced at this point without further
disassembly.
- Carefullyremove oldspring andplace newspring com-
pletewith keeper inposition andpush spring intoplace
in the container. (Fig 11).
- For further disassembly remove central fixing screw
(3) and remove pulley assy. (Fig 12).
- Remove brake spring (10) and washer (8) - only early
type starters, and separate gear (7) from pulley (6). If
necessary, replace rope (12) referring to Fig 13.
- Untie knots A and remove rope from handle (14) and
pulley (6).
- Fita new ropeof the samedimensions andretie knots.
- Check all parts before reassembly.
Fig. 13
Fig. 12
Fig. 11
Fig. 10
Fig. 9
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Reassembling
- Refit gear (7) on pulley (6).
- Windthe ropeontothe pulleyand fitthe gearandpulley
assy onto the bracket pin (11).
- Secure the assy with spring hub (4) and screw (3) (Fig
14).
- Fit re-wind spring.
- Fit new brake spring (10) in its seat (Fig 15) being
carefulto fit theside extensionof the springon itsseat.
- Refit the spring cover and secure with its two screws.
NOTE - Originally the screw (3) (Fig 14,3) had a right
hand thread. Late type left hand thread which is
indicated by ‘S’ stamped on head.
- Pre-tension the spring by completely winding the rope
onto the pulley in the direction of the arrow. (Fig 16).
- When the rope is fully wound give the pulley one more
completeturn toobtain correct springtension. (Fig17).
- The correct tension of the spring is obtained by appro-
ximately 2 turns of the pulley.
NOTE - Only the main spring and spindle must be
greased. Do not grease the brake spring etc, in order to
prevent the accumulation of dust.
Fault checking.
- When the rope does not recoil check:
The spring hub (4), if this rotates, tighten the centre
screw(3). Ifthe centre pinis loose, replacethe bracket
(11).
- When the gear does not engage, check:
Thedistancebetweenthegearandflywheelteethshould
not be greater than 1.5 mm (1/16”) (Fig 18). To adjust,
slacken clamp screws and adjust to correct distance,
retightenscrew; ifthe brakespringis aloose fit,replace
and check the breaking action on the gear.
- Pull the starter rope and check that the rope clip is not
loose and that the rope is of the correct length and
diameter.
Refitting to engine
The distance between the gear teeth and the flywheel
teethmust be1.5 mm(1/16”),the bracketmounting holes
areelongated to providethis adjustment (Fig18).
Fig. 14
Fig. 18
Fig. 17
Fig. 16
Fig. 15
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3. SIDE MOUNTED STARTER VERTICAL ENGA-
GEMENT USA TYPE
NOTA -Alternative type starterabovemay also befitted.
Disassembly:
- Beforedismantling, therecoilspring mustbe lockedby
inserting pin C. (Fig 20).
- Next remove taper pin as per Fig 21.
- Remove centre pin by means of a drift and hammer.
- The spring/gear assy may now be removed. (Fig 2).
Removelockingpin(Fig20-C)andslowlyreleasespring.
To replace:
-Spring: The new spring is supplied complete with
container and new taper pin, the old pin should never
be re-used.
- To detach rope, remove clip A(not to be used again).
(Fig 23).
Fig. 19
Fig. 22 Fig. 23
Fig. 21
Fig. 20
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Fig. 26
Fig. 24
Assembly
- To fit new rope, thread end through hole in gear and
knot.
- Rewind rope as per Fig 24.
- Place spring on gear and preload two turns. Lock by
inserting locking pin. (Fig 25).
- The assembly can now be fitted into the body paying
particular attention to position of the rope Cand the
brake spring M. (Fig 26).
Fig 26. Correct assembly of rope
C. Rope passage
M. Spring brake
- Replace taper pin and remove locking pin. Checking
operation of starter.
- Thegear should nowmove up anddown the slotwhen
the rope is pulled and released. (Fig 27).
Fig. 25
Fig. 27
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4. A - STYLIZED RECOIL STARTER (Fig
28-A)VANTAGE,PRISMA,SYNERGY,
BH,SPECTRA &FUTURA
B - INTEGRAL RECOIL STARTER (Fig
28-B)VANTAGE& PRISMAIndexFigs
28A & 28B.
1. RetainingPin
2. Washer
3. PawlRetainer
4. Washer
5. BrakeSpring
6. StarterDog
7. DogSpring
8. RopePulley
9. RewindSpring
10. Cover
11. Housing (28A) Shroud Assy (28B)
12. Rope
13. Handle
Disassembly procedure
1. After removing the starter assembly from the air
conveyor, releasethe tensiononthe rewindspring by
removing handle and allowing rope to feed back into
starterhousing.
2. Place a ¾” (19 mm) deep reach socket inside the
retainer pawl. Set the rewind on a bench supported
on the socket.
3. Using a 5/16” (8 mm) roll pin punch, drive out the
centre pin.
4. All components that are in need of service should be
replaced.
CAUTION !REWINDSPRING IS NOTIN A CANISTER.
Care must be used when handling the pulley containing
spring because the rewind spring and cover is held by
the bosses in the cover.
Assemblyprocedure
1. Reverse the above listed procedure keeping in mind
that the starter dogs with the dog springs must snap
back to the centre of the pulley.
2. Always replace the centre pin with a new pin upon
reassembly. Also place the two new plastic washers
betweenthecentre leg andretainer pawl.
Discard old plastic washer. The new plastic washers
will be provided along with the new centre pin.
3. Check retainer pawl. If it is worn, bent or damaged in
any manner, replace upon reassembly.
Tap the new centre pin in until it is within 1/8” (3 mm)
of the top of the starter.
CAUTION ! Driving the centre pin in too far will cause
the retainer pawl to bend and the starter dogs will not
engage the starter cup.
Fig. 28 - B
Fig. 28 - A
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Fig. 28 - C
C - STYLISED STARTER WITH PLASTIC
WEDGE (Fig. 28-C)
Thisstarter issimilar toprevious ‘Stylised’starters except
thatthePawlRetainer (2)isnowplastic,andhasextended
lugswhichpass throughthestarterand holdtheassembly
together.
These lugs are locked in position by a plastic wedge (1)
which is inserted between the lugs from the top of the
starter.
NOTE - The plastic wedge may be covered by a decal,
which has to be carefully removed to gain access to the
wedge.
Fig. 28 - C
1. Plastic Wedge
2. PawlRetainer
3. Pawls
4. PawlSprings
5. Pulley
6. Spring
7. Cover
8. Housing
9. Rope
10. Handle
NOTE -Pulley (5),Spring(6),and Cover(7),are supplied
as an assembly when purchased for spare parts
purposes.
DISASSEMBLY/REASSEMBLY
- Release spring tension by unwinding rope.
- Remove decal (if fitted) and pry out the
plasticwedge.
- Holdingstarter assembly togetherin hand,
squeezelugs together.
- Carefullyremove pawlretainer.
- Inspect as for previous stylised starter.
- Re-assembly is the reverse of the above procedure
taking care to correctly locate the Pawl Retainer in the
Pawls.
NOTE - Parts for this starter are not interchangeable
with other starters.
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5. 12 VOLT ELECTRIC START SYSTEM
ELECTRICAL CIRCUIT(Fig 29)
1. ChargingAlternator
2. AlternatorLead
3. IgnitionCut-outLead
4. BatteryEarthCable
5. AlternatorLead,Red,18AWG
6. AlternatorLead(see2)
7. ConnectorBody
8. ElectricStarterLead
9. StarterMotor(internallyearthed)
10. StarterMotorLead(see8)
11. Battery Earth Lead
12. ViewA-A ofFemaleConnectorBody
13/14. Battery
15. Connector
16. Cable,Black,12AWG
17. HeavyDutySwitch
a) BATTERY
Thebattery isa part oftwo circuits,starting andcharging.
Therefore before going into any extensive alternator or
starter checks, the battery itself should be checked first.
Ensure that it is fully charged by recharging for 24 hours
withcharger supplied.In lowtemperatures batterypower
reduceswhilst powerrequired tocrank engineincreases.
NOTE - Loss of charge is normal and temporary during
off season storage.
Sealed Lead Acid Type Batteries
When not in use, store in a cool dry place. After storage,
chargewithchargerunit suppliedfor24hours. Automotive
typechargers mustnot be usedas thesecan overcharge
the battery causing extensive damage. The operation of
the charger supplied can be checked by feel, it should
be warm to the touch whilst in use. The charger has an
outputof approximately 100-150mA, i.e. 1/10of anAmp
at 12V DC.
Fig. 29
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Maintenance instructions for sealed batteries
- Store battery in dry and ventilated area, disconnecting
the battery from the wiring harnesses.
- Avoid storing discharged batteries. It is extremely
important that it is fully charged before storing.
- If battery has discharged, it should be put immediately
on recharge.
- Use only the charger supplied with the battery, or one
withthe followingfeatures:
- maximumcurrentoutput 100-200 mAat 15 Volts DC.
- Beforeprolongedlawnmowerstorage,disconnectbattery
from engine wiring harnesses and ensure battery is
fully charged.
- Avoid shorting battery terminals. The high current
delivered by batteries can overheat and destroy the
insulationand internal connections.
b) ALTERNATOR
A single coil alternator is fitted alongside the ignition coil
(Fig 30) and utilises the same flywheel magnets as the
ignition coil. The air gap is 0.30 mm and is set in
conjunctionwith theHT coilassembly.The alternatorhas
an output of 325-350 mA at 3000 rpm which is sufficient
to keep the battery charged under normal working
conditions.
Air gap setting
Loosen all lamination screws, turn flywheel so magnet is
centred across from solid state module using air gap
gauge, part no. 26990003 (gauge for 0.30 mm air gap).
Tighten ignition coil screw (right side). Rotate flywheel
and repeat procedure setting 0.30 mm air gap between
alternatorcoillaminationsandmagnet.Tightenallalternator
screws
To check the system, remove the plastic connector
housingby insertinga smallbladed screwdriveror similar
device to release the spade connector. (Fig 31).
Connect one probe of a continuity meter to the lead of
thealternator, theother probe toan unpaintedsurface on
the engine for ground. Reverse the meter probes. If
continuity exists in both probe positions, the alternator
assembly must be replaced. (Continuity should exist in
one of two probe positions only). If there is no continuity
in both probe positions, the assembly must be replaced.
Fig. 30
Fig. 31
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c) STARTER MOTOR TROUBLESHOOTING
STARTERS
STARTER DOES NOT FUNCTION
Check for:
- No current to the starter caused by faulty connections
or dead battery.
- Faulty safety switches, ignition or starter switch or
solenoid.
- Engine locked up or parasitic load on engine.
- Shorted open or grounded field coil.
- Open, shorted or bent armature.
- Brushes sticking or damaged.
- Dirty or oily brushes or commutator.
STARTER CRANKS ENGINE SLOWLY
Check for:
- Battery discharged or weak.
- Parasitic load or "tight" engine.
- Worn brushes or weak brush springs.
- Dirty, oily or worn commutator.
- Worn bearings in cap assemblies.
- Defectivearmature.
STARTER SPINS, ENGINE DOES NOT CRANK.
Check for:
- Pinion gear sticking on shaft.
- Damaged pinion or flywheel ring gear.
DRIVE ASSEMBLY SERVICE
Piniongear partsshould bechecked fordamage orwear.
If the gear sticks on the shaft it should be washed in
solventto removedirt and greaseand driedthoroughly.If
damaged,replace parts.
The unit is disassembled by removal of the two end cap
screws, the bendix gear is secured by a snap ring at the
shaftend.
If starter is sluggish in operation, remove end cap and
check condition of armature and brushes; if brushes
requirereplacing thecompleteend capmustbereplaced.
(Fig 32).
ARMATURE CHECK
Ifcommutator barsare glazedor dirty,they canbe turned
down in a lathe. While rotating hold a strip of “00” grade
abrasivepaper lightly onthe commutator, movingit back
and forth. Do not use emery cloth. (Fig 33).
Recutgroovesbetween commutatorbarstoa depthequal
to the width of the insulators.
Using a continuity tester to make certain no continuity
exists between the commutator (copper) and the iron of
thearmature. Rotatearmature andcheck allcommutator
bars (Fig 34).
Fig. 32
Fig. 33
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Re-torquestartermountingbolts to80÷90inchlbs(9.0÷10
Nm).
NOTE - If it is necessary to replace either the starter
pinion and/or the flywheel due to damaged teeth, it is
essential that the starter pinion to flywheel ring gear
mesh is checked on re-assembly. The correct mesh is
1.5mm (1/16”) betweenthe head ofthepinion geartooth
and the base of the flywheel gear tooth. Correct
adjustment can be accomplished by de-forming the
starter mounting bracket accordingly.
Fig. 34
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20
D. FLYWHEEL BRAKE SYSTEM
Tecumseh's Flywheel Brake System provides consumer
safetyby shuttingdownthe engineand lawnmowerblade
within seconds after the operator releases the engine/
bladecontrol at thehandle ofthe lawnmower.
TheBrake StarterMechanism may beused witheither of
twooptions for starting:
1. ManualRopeStart
2. 12Volt Starter System
Each system requires the operator to start unit behind
mower handle in operator zone area. The electric start
system also provides a charging system for battery
recharge when engine is running.
- TOSTOPENGINE(Fig 1).Inthestop positionthebrake
pad (A) is applied to the inside edge of the flywheel; at
the same time the ignition system is grounded out (B).
- TOSTARTTHE ENGINE (Fig2). In orderto restartthe
engine, the brake control must be applied. This action
pulls the brake pad (A) away from the inside edge of
the flywheel and opens the ignition ground switch (B).
On electric start systems the starter is energized to
startthe engine.
On non-electric start systems, recoil starter rope must
bepulledto start engine.
WIRING DIAGRAMS (Electric Start Systems) (Fig 3).
All wiring beyond the connectors on the engine are
supplied by the equipment manufacturer. Check all
terminals and connectors for corrosion and adequate
contact, and all wiring for damage and proper size.
BATTERY
Check battery following the manufacturer's
recommendations. The charging system on the engine
maintains the battery during normal use.
CAUTION:
- Disconnect battery from engine before servicing.
- Beforeremoving flywheel,remove brakepressurefrom
flywheel to make removal of flywheel easier.
- Compress spring by moving lever toward spark plug
and when hole in lever (A) aligns with hole in bracket
(B), secure lever in this position with alignment tool
670298 (Fig 4). Remove flywheel per normal service
procedure as outlined under IGNITION section of this
manual.
Do not damage brake pad or brake mechanism.
Fig. 1
Fig. 2
Fig. 3
Fig. 4
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