After my first outing with my truggy build I took lunch then came out to put it away. It made a horrible loud sqreach sqreach noise as I started it up and put it in the garage. This is a 70 360 bolted to a c6. The whole truck is a wild custom build from front to back. The motor I was told had a mild rebuild. No idea what was done but I drove it before pulling it from the doner truck. Had friends over so I asked them got no certain answers. By my self now pulled the cranny inspection plate everything looks ok and the starter looks disengaged. Put a socket on the crank and Every Time I get past the timing mark I hear a scraping almost ringing noise for a quarter turn of the crank. I'm not new to Fe's just not eager to tear it apart if I don't need to. Help please. RKD.

 

Hmm, that is weird. I am no expert and I have never had that problem before, but since you said its making almost a ringing sound or something like nails on a chalk board, I would check to see if you have a bolt or something scrapping on your flex plate, just the first thing that comes to my mind. Other than that I suppose it could be something with the crank, but I can't think of anything in the crank that would have enough open room to squeal like that. Kinda like a tuning fork I guess is how I'm thinking of it, to make a high pitched squeal the part has to have enough room to vibrate or resinate, like your flex plate for instance. I suppose another thing to check would be your timing gears. Is it a squeal or more of a grinding sound?

 

Check that the separator plate, the plate that sits between the engine and the tranny bellhousing, isn't hitting the flywheel.

Sometimes they get buggered up, and depending on the temperature of the motor, how much crankshaft end play you have, and some other stuff, it may touch the flywheel.

 

Thanks for the ideas. Had my wife take a listen and she was clueless. Gave her the wrench but she could not turn it. Slipped a pipe over the handle and she slowly turned it over as I crawled under. The noise defiantly came from the flexplate or the other separator plate. Stuck a wooden hammer handle in between the two and the tone changed. I'll start searching from there. RKD.