I recently bought a GM Goodwrench 350 crate motor. The motor runs great but makes an extreamly loud screaming noise at about 3000rpm and above. It will make the noise in any gear or in park, all at about the same rpm. The motor only has 5000 miles on it and we have changed the oil many times. I have no idea where it is coming from and any suggestions would be great.

could it be a belt squeal, maybe the bearings in the water pump, alternator or power steeing pump? Just throwing some suggestions out there. If it makes the noise in park, get a buddy to stick his head under the hood while you feather the throttle, good luck graemlins/thumbsup.gif

try running it without the belts on it to try to determine where the noise is coming from and reinstall the belts one at a time until the noise returns.

Check to see if the timing pointer is dragging on the balancer, or the tranny dust cover touching somewhere.

I heard one doing that and it turned out to be a slight leak at the carb gasket causing a whistle

Originally posted by Dean:
I heard one doing that and it turned out to be a slight leak at the carb gasket causing a whistle I had one that did that. Drove me nuts. If you go to WOT, vacuum will go to 0 and the noise should go away. If it doesn't, then it's not a vacuum leak.