Power steering pump belt length

[bteutsch]

I have a 1971 302 with factory v pulleys, I have added a three groove pulley on the harmonic balancer and I am using the BC Broncos multi steer power steering bracket with the BC Broncos power steering pump and single groove pulley. Anybody know what belt length would fit this arrangement, or know what may have worked in the past? Does the belt use the water pump pulley as well as the three groove pulley? I'm currently only using the water pump pulley, because I'm stupid and put the power steering pulley on backwards. It works but slips if it gets wet. I'm going to take it apart and put it back together the right way. Just didn't know if there was a standard belt length. If not I'll do like I did before, measure, try it, take belt back and repeat until it works.

 

[Glass Pony]

I don't have the BC Bronco's stuff but I went to a WH's Saginaw pump and bracket and had to go up to a 49-1/2" belt.

 

[thegreatjustino]

Not a standard length. Get a fabric tape measure and loop it around the three pulleys. This will get you a decent starting point.

Most autopart stores will take a belt back shortly after you buy it if you explain the issue you're having with trying to find the correct length belt. That or buy two or three different belts, try all them, keep the one that works the best, then return the others.

 

[bteutsch]

Thanks for the advice!!! That's what I basically did last time. Kind of trial and error. I think it took 3 or so try's but it worked out. Just thought maybe there would be a standard length that might save some time. Thanks guys..

 

[Rockstar Bronco]

Resurrecting an old post, but it seems necessary.

To answer the question nobody seems to be able or willing to answer ...anywhere on the internet; with oem/stock ps pump / alternator and no a/c (single fan pulley), it's 41" on the fan/alt belt (inside pulley) and 42.5" on the ps pump (outside pulley), depending on the width of the belt relative to the pulley. The ps pump belt is a bit wider than the alt belt (17/32 vs 15/32) ...at least on mine. Check yours to confirm.

Goodyear has an easy 5 digit numbering system for v belts. All 15/32" wide v belts start with 15, and all 17/32" v belts start with 17. The last 3 numbers are the length. So, for example, I use a 15410 (15/32" x 41") for the alternator, and a 17415 for the ps pump on my stock 74 Bronco.

All that being said, the best method IS to use a flat cloth tape, but that's tough to do b/c the tape won't stay on the outside of the pulley, unless you have 6 hands. It's key to remember that v belts are measured and sold by their OUTSIDE circumference, so if you use a string to measure, you'll come up WAY short. Further, depending on the width of the belt, you can't always tell how far out of the pulley the outside circumference of the belt will sit. So, to some extent, it's always hit or miss, but start with the numbers above, and you may end up making one or two fewer trips to the parts store (or worse, returning online orders).

 

[m_m70]

I've always had good luck measuring with 1/2" nylon rope.