How to find or where to buy alternator belt

[randy500]

Your pulley looks worn out, they do wear, try a new one or another used one.

[randy500]

New pulley, not sure on the diameter...
https://www.speedwaymotors.com/1955-...ump,12678.html

[dmjlambert]

I never did find a source for Gates belts in the 8 series such as 8525 that RustyPile suggested. Gates green stripe belts that volksworld mention sound good, from what I read online they are heavy duty.

[dmjlambert]

OK I had O'Reilly's order me a Gates XL 9525. There is no such thing as 8525 any more. The 9525 did not fit, it was way too wide. So I took it back and had them give me a 7520, which is the exact same one I was using before. I put it on. As you can see, it substantially fills the groove and it is noticeably wider than the squeaky 7520 I am replacing. In this picture I held the old belt in the next groove of the water pump pulley for comparison.



I do not remember the old 7520 belt riding high in the alternator pulley when I first installed it, but I suppose it could have been that way and I was not paying attention, and perhaps that causes the belt to wear and get narrow. I suppose I will need to try one of those deep groove pulleys but I don't know if they are compatible with the 7 series belts. If it is, then I will need to get a longer belt because this one is going to be too short to fit over the pulley. Then I will get into interference and rubbing on the power steering pump, and very limited range of adjustment. I don't know if a 1972 upper alternator bracket would allow me to really use a wider range of adjustment without the belt rubbing on the power steering pump.



The stock alternator has a much wider range of adjustment because there is a big indentation in the case that allows the valve cover it fit in it. This alternator is a CS144 which does not have that indentation and is also an inch bigger. What I would really like is an alternator lower mount bracket that holds the lower alternator out 1 more inch away from the valve cover. Then I would have better range of adjustment.

The problem is if I get a belt that barely slips over the pulley when the alternator is adjusted all the way in, by the time I adjust the belt the alternator is already at the all-the-way out position and belt is too loose. So I need to get a short belt, and remove the lower alternator bracket and rotate the whole bracket and alternator down just to put the belt on. There is no way for me to win it seems.

Overall, I'm pretty bummed out. I just want this belt crap all figured out. If anybody has a GM alternator pulley that they know works with the 7 series of Gates belts, fills the groove but does not result in the belt riding high, I would be happy to buy it and pay postage.

[gmc684x4]

Look at the 88 and up pully setups at your local junkyard craigslist etc

You will need a new water pump grab the ps as well as the altenator if it has different locating ears water pump pully and crank pully

I am doing this for my 72 to be able to ditch the vbelts

With the rust cleaned out now your new belt will proubly last much longer now

[dmjlambert]

I would like to do that as well. I am inexperienced at shopping junkyards, and don't have a lot of time for that. I suppose it will be worth taking some vacation time. I will have to figure it out. If somebody here knows of an opportunity to pick up a serpentine setup and would like to tell me about it, or pull it for me and ship it, I would like to pay for one. I don't care too much for the new aftermarket serpentine setups that I see in catalogs and web sites for $2000-$3000, but would not mind spending some dozens or hundreds of dollars.

I don't and didn't have any rust on any of the pulley grooves. The pulley for the alternator was new, and the water pump and engine crank pulley were cleaned up and painted, and the truck has been a daily driver since then. So there's no time for rust to form, this truck keeps moving. Any rust that was perceived from the pictures was not there, it is the way the light falls when taking pictures I suppose.

[BigBird05]

If you have a local Pick a part there are guys just hanging around that you can pay to get the parts off for you.

[dmjlambert]

The 7520 belt riding high in the alternator pulley as shown in the picture above had to be fixed. That pulley was from my last alternator, which was a cheap Chinese 12SI that only lasted 1 year. I transferred the pulley and fan onto the Delco Remy USA CS144 alternator because that alternator came with a serpentine pulley. The V-belt pulley was probably intended for 3/8" belts. To solve the problem I bought a new deep groove pully and fan set.


Now the new wide belt does not fill the groove. I did not expect it to because it is a deep groove pulley. It sure is nice.


The new belt fills the groove on the engine and water pump. Looks nice there as well. No more squealing.




And finally, I bought a used Ingersoll Rand Impactool. I've always wanted one of these and didn't pull the trigger until now.

[RustyPile]

Originally Posted by dmjlambert

OK I had O'Reilly's order me a Gates XL 9525. There is no such thing as 8525 any more……………. <snip>…………...

That's a new one on me.. I'm a retired mechanic and worked in the field for over 30 years.. Been retired quite a while and these days I just "piddle" with my own stuff.. About 2 years ago, I replaced the belts on my C/10 using Gates "8" series belts.. I'm not saying you or O'Reilly's are wrong.. Perhaps the locally owned parts store I patronize had some NOS belts...

[dmjlambert]

Originally Posted by RustyPile

That's a new one on me.. I'm a retired mechanic and worked in the field for over 30 years.. Been retired quite a while and these days I just "piddle" with my own stuff.. About 2 years ago, I replaced the belts on my C/10 using Gates "8" series belts.. I'm not saying you or O'Reilly's are wrong.. Perhaps the locally owned parts store I patronize had some NOS belts...

Yes I wonder about that, too. Anyway, the 8 series would be too wide for this engine, 7 series is just right and I didn't know it because mine was prematurely worn down by me using the incorrect alternator pulley.