Inliners International Forums General Discussion Engines 292 Knock

I have a 292 chev that has been rebuilt twice and still has the same knock. The last rebuilt replaced pistons, pins, rods, machined all bearing surfaces and everything else was new. The only thing not new was the Comp camshaft (very Mild). It had less than 300 miles from the first rebuild, so they just instaled new lifters. Could it be possible that the notches for the rod clearence was not machined right by comp cams. Has anybody had a clearence problem? Also, might note that the knock is louder when the engine is pulling. Any help would be great... not looking forward to tearing down this engine a third time.

any metal in the oil ? did you align bore the block and turn crank ? this isnt normal for this engine, there very reliable. sure it isnt spark knock from poor gas ?

Does it knock w/it just parked & reving the engine?

MBHD

Louder when pulling usually means detonation. Are you running high test? If not run it and see what happens. Also check the advance. Too much can also cause detonation.

Knocking or thumping? Assuming you run an automatic, have you checked for a cracked flexplate or loose/worn converter bolts?

Yes, the camshaft notches will be an issue if you are using a camshaft for a 250 in a 292 engine. Did you inspect the camshaft for evidence of contact by the connecting rods, should be easy to spot on either the connecting rods or cam barrel. Another source of the knock could be from excessive cam thrust. This is often overlooked by many when rebuilding these engines and will produce a knocking/thumping sound that is hard to find. Did you replace the thrust plate and thrust ring when you rebuilt your engine.

One more thing When you replaced the Cam Did you heat the gear before putting it on the cam? If not this could be your Issue If you can not seem to pin point the knock. The cam may vary well be walking back and fourth in the block.This to will sound like a Knock with out a dout.

I put new gears in an engine and they knocked like a rod knock. Put in another new set of gears - knock went away.

Sorry to take so long to get back to your great suggestions. Wanted to check with shop for some answers. There is no metal in oil, The block was align bored and crank was turned. It is the correct cam (fuel pump lobe correct position). The cam gear was heated before pressing on, however the thrust plate looked good and was not replaced. Detonation was my first thought, replaced the very old stock dist. with a rebuilt stock dist. Knock was still there. The gas is fresh, will try high octane, if knock is gone, will have the dist set up, Then if knock is still there, will pull cam, replace gear and thrust plate..Thanks for your help!!