I recently purchased a new 2 grove upper pully for my 1968 z/28 302 motor part # 3770245, and when I put it on the back side rubs the water pump #3859326 and the pully groves don't match up. The pully needs to come forward about 1/8" - 3/16". does anyone make spacers for this problem? I suppose I could fabricate something out of 1/8" or 3/16" steel plate.
Stop, I answered my own question, yes the do make shims for this problem, ordered a 3 shim set on ebay.
Napa has them, too -
What water pump casting are you using ? Z pump has a longer shaft height, remember -
Regards,
Steve
3859326 supposed to be the right pump.
GM pulley, or reproduction ? Reason why I ask, I have the same setup, read on another thread that there is a reinforcement required that would likely make up the 1/8" difference you are seeing, supposedly in the AIM. Hub height for the 326 should be 5-11/16".
Just trying to prepare for the eventual restoration routine - I hate mismatched pulleys and thrown belts.
Regards,
Steve
I believe it's repop with the correct part # embossed in it.