8)Restrickedexhaust gas outlet. Carbon deposit in combustion space.
9)Engine detonating due to low octane gasoline with heavy load at low speed.
11-5 ENGINE KNOCKS
1)Gasoline of poor quality or low octanerating.
2 ) Engine operating under heavy load at low speed.
3)Carbonorleaddepositsincylinderhead.
4)Incorrectsparktiming.
5 ) Losse or burntoutconnectingrodbearing.
6)Worn or loose piston pin.
7)Engineoverheated.
11-6 ENGINE BACKFIRES THROUGH CARBURETOR
1 ) Water or dirt ingasoline or poorgrade of gasoline.
2 ) Stickyintake valve.
3)Overheated valves, orhotcarbonparticles in engine.
4)Enginecold.
