TROUBLESHOOTING
8-1
EAS28451
TROUBLESHOOTING
EAS28460
GENERAL INFORMATION
TIP
The following guide for troubleshooting does
not cover all the possible causes of trouble. It
should be helpful, however, as a guide to basic
troubleshooting. Refer to the relative proce-
dure in this manual for checks, adjustments,
and replacement of parts.
EAS28470
STARTING FAILURES
Engine
1. Cylinder and cylinder head
• Loose spark plug
• Loose cylinder head or cylinder
• Damaged cylinder head gasket
• Damaged cylinder gasket
• Worn or damaged cylinder
• Incorrect valve clearance
• Improperly sealed valve
• Incorrect valve-to-valve-seat contact
• Incorrect valve timing
• Faulty valve spring
• Seized valve
2. Piston and piston ring
• Improperly installed piston ring
• Damaged, worn or fatigued piston ring
• Seized piston ring
• Seized or damaged piston
3. Air filter
• Improperly installed air filter
• Clogged air filter element
4. Crankcase and crankshaft
• Improperly assembled crankcase
• Seized crankshaft
Fuel system
1. Fuel tank
• Empty fuel tank
• Clogged fuel strainer
• Clogged fuel tank breather hose
• Deteriorated or contaminated fuel
2. Fuel cock
• Clogged or damaged fuel hose
3. Carburetor
• Deteriorated or contaminated fuel
• Clogged pilot jet
• Clogged pilot air passage
• Sucked-in air
• Damaged float
• Worn needle valve
• Improperly installed needle valve seat
• Incorrect fuel level
• Improperly installed pilot jet
• Clogged starter jet
• Faulty starter plunger
Electrical system
1. Battery
• Discharged battery
• Faulty battery
2. Fuse
• Blown, damaged or incorrect fuse
• Improperly installed fuse
3. Spark plug
• Incorrect spark plug gap
• Incorrect spark plug heat range
• Fouled spark plug
• Worn or damaged electrode
• Worn or damaged insulator
• Faulty spark plug cap
4. Ignition coil
• Cracked or broken ignition coil body
• Broken or shorted primary or secondary
coils
• Faulty spark plug lead
5. Ignition system
• Faulty CDI unit
• Faulty pickup coil
• Faulty stator coil
• Broken generator rotor woodruff key
6. Switches and wiring
• Faulty main switch
• Faulty engine stop switch
• Broken or shorted wiring
• Faulty neutral switch
• Faulty start switch
• Faulty clutch switch
• Improperly grounded circuit
• Loose connections
7. Starting system
• Faulty starter motor
• Faulty starter relay
• Faulty starting circuit cut-off relay
• Faulty starter clutch
EAS28490
INCORRECT ENGINE IDLING SPEED
Engine
1. Cylinder and cylinder head
• Incorrect valve clearance
• Damaged valve train components
To Next Page
Loading...
Need help?
General
