swgear

Installed a new P/S pump and pulley.-Correct type ordered from Zip Corvette) Now the Pulley is rubbing on the frame --immediately below. I have taken it to a local corvette specialist and they have ruled out any in correct installation on my part. They also ruled out using a shorter/smaller belt. They claim that the frame may be slightly bent and are recommending placing shims under the engine mounts in order to provide enough clearance. A little history--I'm replacing the pump and pulley do to the fact that the pulley came of the shaft a few weeks ago--possibly due to it rubbing the frame. I'm really not sure. But non-the-less it came off the shaft--as if it had worn the shaft and was really loose.

Any insight on using shims to rectify this problem would be great

thanks

scott

rugerm44

I think I would check the motor mounts.If there ok let a body shop check the frame.I would want to know why the problem was happening in the first place.

bobs77vet

wow thats strange, i recently replaced mine and for sure the spacing is tight. for it to be rubbing certainly would make you think there were some real issues....i am with rugerm44 and would want to look at the motor mounts especially the passenger side and the transmission mount make sure the engine isnt sitting cocked. does you car drive straight and is there any evidence of a major collision? i wonder if you could find a slightly smaller diameter pulley.

swgear

Thanks for the quick response--You are correct, the clearance is surely tight--approx 1/8th inch. Car drives well, no problems that I can tell. e.g frame bent etc. I forgot to mention it is a 70 LT1.

KapsSA

What size belt ARE you using?
Seems a shorter belt would pivot the pump up from the frame a bit.
7/16"X36 1/2" or 3/8"X36" is correct, at least for my years.

Were there obvious rub marks on the frame from your old pulley?

KapsSA

Don't know what year or motor you're running, but in another thread you mention buying a cast iron pulley.

Quick look in DocRebuild's catalog shows a 6 1/2" diameter cast pulley and stamped steel pulleys at 5 3/4" diameter.

What's the actual diameter of the pulley you bought?

edit...I see now it's a 70 LT1
The 6 1/2" cast is a big block pulley.

swgear

Not sure of the size--it is currently at the garage. I did order the correct belt from Zip Corvette. I also asked the garage about a shorter belt and they said that that would not resolve the problem!?

swgear

I bought the cast Iron Pulley which I believe to be the correct one--I'm running a 1970 LT1 350--original/correct numbers matching motor

KapsSA

Cast iron is correct for LT1 according to DocRebuild but he doesn't give the size for the small block one.
Size of old pulley, rub marks on the frame?

exposingtime

Are the studs for your pump correct?

I had an issue where the studs were incorrect, so the pulley was out of alignment.

You might be having a similar issue.

swgear

Best I can tell the studs are correct

thanks

tekvette

I would put new motor mounts in and go from there.