Maintenance
2.39
General Troubleshooting -- Continued
Piston Damage
Symptoms: Hole in piston.
S W ater in carburetors or fuel
S Lean fuel mixture (see lean condition troubleshooting)
S Detonation from incorrect ignition timing, poor quality fuel, modified cylinder heads, excessive
carbon buildup, etc.
S Incorrect spark plug
S Overheated engine
S Flywheel key sheared, keyway damaged, flywheel damage
S Crankshaft out of index
Symptoms: Eroded piston (exhaust edge of crown) or scuffed piston.
S Lean fuel mixture (see lean condition troubleshooting)
S Detonation from incorrect ignition timing, poor quality fuel, modified cylinder heads, excessive
carbon buildup, etc.
S Engine overheating (inspect cooling system)
S Crankshaft out of index (see engine section)
S Flywheel key sheared
Symptoms: Seized or scuffed piston.
S Water in oil
S Oil pump failure
S Oil tank vent problem restricted, check valve in backward
S Pinched or restricted lines
S Lean fuel mixture (see carburetion)
S Poor quality fuel
S W ater in fuel
S Engine overheating
Symptoms: Cracked piston crown.
S Hydrolocked engine (water or fuel)
S Foreign material in engine
Symptoms: Cracked/broken piston skirt.
S Excessive piston to cylinder clearance
S Foreign material in engine
S Sharp ports
S Modified engine
S Hydrolocked engine (water or fuel)