I have a 1966 inline 6 250 160HP gm...When the engine is idling I hear a on and off squeal, scream, and chirp coming from the motor. I checked the belts, greased the pully's and still the same sound. I put my ear next to the crankshaft area of the motor and it seams thats where its coming from. The sound could be telescoping, hard to tell with the engine in your ear. But its on and off....when you hear it you can almost invision a ball bearing going round and round squealing. But it starts at a mid squeal tone and rapidly increases in pitch until its a very high pitch squeal and then it stops, engine sounds great for a few minutes then starts it all over again, sometimes with a grinding type noise. When I give it gas it seems to go away. Oil clean, engine seems like its pumping oil, not sure if its pumping correctly. How does a bad crankshaft bearing sound?
