2012 Kawasaki KX250F Owners Manual - Page 168

166 TROUBLESHOOTING GUIDE Fuel/air mixture incorrect: Air cleaner element clogged, poorly sealed, or not installed Fuel contaminated with water or foreign matter Fuel tank cap air vent obstructed Throttle body assy holder loose Air cleaner duct loose Fuel line clogged Fuel pump defective j oil level too high • Engine Engine oil too high • Crankshaftviscosity worn or damaged • Drive chain bearing trouble • built up in combustion chamber • Carbon quality poor or type incorrect • Fuel plug type incorrect • Spark ECU defective • Engine overheating Firing incorrect: Spark plug dirty, broken, or gap improperly adjusted Spark plug type incorrect ECU defective Fuel/air mixture incorrect: Knocking: plug loose • Spark Cylinder insufficiently tightened • Cylinder head bolt loose • Cylinder or piston worn • No valve clearance • Valve spring broken or weak • Valve not seating properly (valve bent, worn, or • carbon accumulation on the seating surface) ring worn, weak, broken, or sticking • Piston Piston ring side clearance excessive • Cylinder head damaged • Cylinder head gasket warped • Cylinder gasket damaged • Decompression trouble • Compression low: • • • body assy holder loose • Throttle Air cleaner • installed element clogged, poorly sealed, or not • Air cleaner duct poorly sealed Improper acceleration: Throttle valve does not fully open Air cleaner element clogged Fuel contaminated with water or foreign matter Brake dragging Clutch slipping Engine overheating • Compression high: Carbon built up in combustion chamber Engine overloaded: Brake dragging Clutch slipping Engine oil level too high Engine oil viscosity too high Drive chain trouble