engine noise
tdaga
10-15-2005, 10:32 AM
is there any test i can perform to see if a bearing is gone...and also a lifter... i have a noise that seems to be coming from the lower end but sounds like a lifter.. took off valve covers and all rocker arms seem normal but there is one that has no oil shooting out. thanks
dogbreath077
11-02-2005, 09:46 PM
What engine? if it is the 305, then you have a worn out camshaft.
to test the bottom end. defeat each cylinder one at a time. If the noise goes away, then it is a rod bearing or wrist pin. The wrist pin sounds like a loose rocker arm. the bearing sounds like a hammer knocking inside. also, revhard in neutral, and then come off. If it knocks hard on reving but not on decell, it is a rod bearing.
to test the main bearings: slowly rev the engine and bring it to 2000 rpm, let it float there a bit, then slowly come down to idle. If there is a deep knocking on accel and decell, but not float, then it is a main bearing.
to test the bottom end. defeat each cylinder one at a time. If the noise goes away, then it is a rod bearing or wrist pin. The wrist pin sounds like a loose rocker arm. the bearing sounds like a hammer knocking inside. also, revhard in neutral, and then come off. If it knocks hard on reving but not on decell, it is a rod bearing.
to test the main bearings: slowly rev the engine and bring it to 2000 rpm, let it float there a bit, then slowly come down to idle. If there is a deep knocking on accel and decell, but not float, then it is a main bearing.
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