Chapter 6 Alternator; Alternator; Troubleshooting Electric Start Engines; Troubleshooting For Both Mechanical And Electric Start Systems - Tecumseh VLV Technician's Handbook

Alternator

The 350 Milliampere charging system consists of a
single alternator coil mounted to one side of the solid
state module.
Alternator
Lamination Screws
Alternator Coil
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. This
system will maintain the charge level under normal use
conditions.
Do not operate engine with
CAUTION
charging system disconnected.
Doing so may result in damage to diode.
System Checking
Set volt/ohm meter to 0-20 volt D.C. scale for test.
The battery MUST BE IN CIRCUIT for test to perform
properly.
1. Connect voltmeter at the battery (should read
battery voltage).
2. Next, start engine -voltage should read higher than
when engine is off.
If there is a change upward in voltage, the charging sys-
tem is working.
If there is no change in voltage, the alternator should be
replaced.
6-1
Solid State Module
Ignition Coil
Lamination Screw
NOTE
NOTE
NOTES
Chapter 6
Alternator

Troubleshooting Electric Start Engines

The 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 mis-adjusted
Valve clearance too wide
Compression release not functioning
Flywheel brake is still applied
Maximum compression should be 90 PSI (6.2 Bar). 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'' (.10 mm) if
necessary to gain more compression relief. If compres-
sion is still above 90 PSI (6.2 Bar), check the camshaft
compression relief mechanism.
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