Chapter 6 Alternator; Troubleshooting Electric Start Engines; Spark Plug Service - Tecumseh VLV Technician's Handbook

ALTERNATOR
LAMINATION SCREWS
ALTERNATOR
COIL
ALTERNATOR. The 350 Milliamp charging system
consists of a single alternator coil mounted to one side
of the solid state module.
NOTE: This charging system is designed to maintain a
charged battery. Most O.E.M.'s supply a trickle charger,
which should be used before and after off season
storage. Then this system will maintain the charge level
under normal use conditions.
Do not operate engine with charging system
disconnected. Damage to diode may occur.
CHECKING THE SYSTEM. Connect voltmeter at the
battery (should read battery voltage). The battery MUST
BE IN CIRCUIT for test to perform properly. Next, start
engine -voltage should read higher than when engine
is off. If there is a change upward in voltage, the charging
system is working. If there is no change in voltage, the
alternator should be replaced.
NOTE: Set volt/ohm meter to 0-20 volt D.C. scale for
test.
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Chapter 6
ALTERNATOR
SOLID STATE MODULE
IGNITION COIL
LAMINATION SCREW
Not For Resale

TROUBLESHOOTING ELECTRIC START ENGINES.

Following is a list of possible problems and causes.
DEAD BATTERY
Extended storage without charging
Excessive cranking
Faulty starter
Faulty wiring
Faulty alternator
Faulty battery
BATTERY O.K., ENGINE WON'T CRANK
Brake cable defective
Faulty starter switch
Poor electrical connections
Faulty starter. See starter section
ENGINE CRANKS SLOWLY
Weak or discharged battery
Faulty starter
TROUBLESHOOTING FOR BOTH MECHANICAL
AND ELECTRIC START SYSTEMS
IF ENGINE PULLS OR CRANKS HARD
Excessive engine drag due to obstructions under
deck.
Mower traction drive misadjusted
Valve clearance too wide
Compression release not functioning
Compliance brake is still applied
Maximum compression should be 90 PSI. If
compression is higher, de-carbon the valve seat and
head area and check valve clearances. Exhaust valve
clearance may be set as low as .004'' if necessary to
gain more compression relief. If compression is still
above 90 PSI, check compression relief part of
camshaft.
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