pulley clearance?

[rick0312]

I installed the water pump pulley over a new alluminum pump, and it is way too close to the crank pulley. pulled the crank pulley and water pulley off of an 305. should I go with a smaller water pulley or a smaller crank pulley?
Thanks again.....rick

[Green Machine]

They always run real close, if they don't rub you are OK. Might loosen the water pump and see of you can lift it up a hair, might be some slack in the holes in the pump. 3/4 ton used a smaller top pulley that spins the pump faster that would give plenty of clearance, but wastes HP spinning faster IMHO. In fact I would like to get a 1/2 pulley to swap out for the one on our C20.

[HoupPhotography]

I disagree based on the photo. If they are that close, when you line them up they look like they will touch, it could just be the angle.

Why can't you use/buy the original or OE replacement for that motor?
If it's a SBC, it's a close tollerance motor to begin with, I think your pushing your luck a little with this one.

[rick0312]

i pulled up on the pump and it gave me enough clearance to where it does not touch, but it is close about 1/32-1/16". I think thats a bit too close for me. I quess I should swap the 7 1/8" pulley for something a litlle smaller. I hate to buy one of those cheap chrome pulley's from summit though.

[Green Machine]

Here's a couple of pics from 2 of our trucks. The first one is from the 70 without power steering and the second is the 68 with power steering. The pulleys on both are original, except the extra power steering on the 68. They run real close as you can see, but they have been that way for years and never had a problem, I think you are good to go.

[rick0312]

Thanks Green machine for the pics. i didn't think they ran that close, but from the looks of things yours are as close as mine. I'll give it a go...Thanks' again!


just checked out your trucks....real nice! I love the 68! Nice work!

[Green Machine]

Your're welcome, glad I could help. And thanks for the complements.