2011 Kawasaki KX250F Owners Manual - Page 165

TROUBLESHOOTING GUIDE 163 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 Compression low: oil level too high • Engine Engine oil viscosity too high • Crankshaft worn or damaged • Drive chain bearing trouble • Knocking: Carbon built up in combustion chamber Fuel quality poor or type incorrect Spark plug type incorrect ECU defective 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 gasket damaged • Cylinder head head warped • Cylinder gasket • Decompression damaged trouble • Engine overheating Firing incorrect: Spark plug dirty, broken, or gap improperly adjusted Spark plug type incorrect ECU defective body assy holder loose • Throttle cleaner element clogged, poorly sealed, or not • Air installed • Air cleaner duct poorly sealed Fuel/air mixture incorrect: 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 dragging • Brake Clutch • Engineslipping level too high • Engine oil oil too high • Drive chainviscosity trouble • Engine overloaded: