V belt question.

[TJ1978]

I’m at the point to order belts for the engine. 350 sbc and I’m thinking based on this diagram I’ll need 2 belts.

I don’t know what size or what gates belts to get? Or if I go with 3 belts which ones.
Links are appreciated..

 

[nvrenuf]

That crank pulley might be a different diameter than stock, either way you’re going to have to make a few trips before you get them both right. I’d start with belts for a mid 70’s 1/2 ton truck without a/c.

If you have the pulley grooves to do it AND they all line up, maybe try to run the p/s belt across the water pump too for extra “insurance”.

 

[TJ1978]

Yeah, the water pulley is stock GM. PS and crank are aftermarket “fancy” stuff. I may still have the GM ones laying around. I’m going to try my luck with these aftermarket ones first.

 

[nvrenuf]

Oh yeah, keep the bling pullies. I just meant that they may prevent you from finding a “one and done” belt, you’ll likely buy something close but have to swap it to fine tune the fit.

 

[TJ1978]

I measured using a string but I think I mistakenly measured the length how the string lays in the pulley grove. All the belts I got are not nearly long enough.
Even with the PS and ALT al the way towards the block.

do I measure with the string on the edge of the pulley?

 

[TJ1978]

I bought a 40” and 42 inch belt and both are way to small.

i have the PS straight up and the ALT adjuster about in the middle.

 

[TJ1978]

Got the right belts... now. If you look at the pictures, can I use washer to move the alternator out a bit?

secondly the PS belt of I use the inner most grove seems line it will rub on the water pump. If I move it to middle groove I will have to trim and shim the PS pulley.

what do you guys recommend to line these belts up properly?

 

[TJ1978]

Alternator belt is lined up now with a few washer.

now in regards to PS can I run on different pulley groves to make not run straight? As in the first grove towards the block on the water pump and middle groove of the crank pulley?

 

[dyeager535]

I have a pile of belts just for this reason lol. Not like I need them but once every 10 years, but makes it a whole lot easier to find the size that works instead of a bunch of trips to the parts store!

Edit: call me crazy, but from the pics it looks like the crank pulley is the problem. It needs to be spaced out. You don't want belts running at an angle.

 

[TJ1978]

Alternator belt is lined up now disregard the above pic

 

[Wes Harden]

!st and most important is having the crank pulley and water pump groves line up. The power steering pump may not be able to go around water pump. Iirc if the p/s pump belt does go around the water pump the W/p needs a 3 grove pulley.

 

[TJ1978]

@Wes Harden
How do you shim the crank or WP pulley, if it were needed?

The only reason I did one belt from PS to WP to Crank was on recommendation here. I initially was only going to do PS to Crank, which I can still do. I just need to get a smaller belt

 

[Wes Harden]

Yeah I remember that rec, and I blanked out on the w/p pulley needing 3 groves.
Do any of the groves line up between crank and w/p?

 

[TJ1978]

I think I have it sorted out. I’ll post pictures later.