I just put in a reman engine in a friends ride. It of course is crap like 99% of them! It has a wrist pin making some noise under load at the top of each gear. Is there any method for islolating which cylinder it might be comming from without R&I? I was thinking just pulling 1 plug wire at a time might be the only option since the injectors cant be unpluged.

 

Try a stethescope on each cylinder location while it's running - it's amazing what you can hear with one - they have them for cars at HarborFreight and such. A long screwdriver will work too - put the tip on the location, and put the blunt end against your ear - it'll pick up the vibrations.

 

Wrist pin noise that I've heard was worse at highest vacuum. Can you hear it all at idle? Is it a dead knock or a rattle sound? I'd suspect something else with the info you've given.

 

It's for sure a wrist pin noise but it isnt noticeable at idle only in gear and 90% of the time at the top of each shift point. I did use the stethescope but nothing too strange at idle or at 2K yet since the engine is still tight for the most part.

 

If she's rattling at the top of each gear she's not going to last very long regardless. I'd yank it and tear into it before something lets go. Knowing which one is causing the noise does you precious little good if you can't fix it without tearing the motor down anyway. And if it's a wrist pin it should be fairly obvious which one when you take it apart.

 

Just rebuilt a 350 for a friend the second time, when he had all the machine work done he didnt bother having new wrist pins put in, had to go into it again and have him have new pins installed, that was a learning experiance for him.

 

I actually wanted it to explode so it would have made it easy to find the problem but it hasent let loose yet.

I did get some time to check it out, cyl #7 or to keep this chevy well say #5 is the bad hole. I ended up using a spark tester to kill the hole. I dont know what thier smoking when this particular engine place built this engine but if they want some one to check thier heat tabs they shouldent put them where the motor mounts cover em. I hope the next one is good because that would be 4 engines in a row from this place that were bad, of course not in the same vehical.