Serious belt problems with a 383

[Loren]

I have a 383 in my 72 chevelle. I got the car from one of my friends when it had a 350 in it. The fan-alternator-crank belt were constantly coming off the whole time he had the car. I bought it from him and i had a motor out of a mid 80s cutlass lying around which i took the pulleys off from and put on the 350 in the chevelle. they went on in exactly the same way as the old v-belt and ran fan-alternator-crank just like before but instead they were a wider pulley about 1inch wide with 5 little Vs. Any way i put those pulleys and the belt on the 350 and never lost a belt again. Eventually i blew up the 350 bought a brand new 383 and put the whole pulley system on there. Never had a problem. Randomly one day my crank pulley cracks and cuts the belt. i take it off and go to all the scrap yard and part stores around where i live and they all tell me that theyve never seen a pulley like i have before or that its part of a serpintine system and they wont listen otherwise. So i go home and put the old v bels back on and it started throwing belts again. ive since changed every pulley every bracket and 3 or 4 belts and they havent stayed on since. If anyone recognizes the kind of crank pulley i had and where to get one, or any other solution please send me an email at my girlfriends email. [email protected]

[paul67]

Any chance of a pic

[NOVA]

I know this sounds redundant and youve probably heard this several times but the belt/pulley system needs to be perfectly aligned.

Todays belt systems have very little tolerance for mis-alignment, specially serpentine systems, they may look fine but there off a little and it will throw belts, or squeal, or wear belts unusually fast and it usually stems from mis alignment.

There actually is a tool called the lazer alignment tool for aligning pulley systems, not suggesting you buy one, just saying that pulley systems today are very fickle, and it doesnt take much, I also lean towards your pulleys being off because you say, you never had problems until switching pulleys.

good luck.

[Jim Nilsen]

Get a premium cogged v belt from Gates. They are more money but even with a slight misalignment I have had them work. These belts are cogged on the inside diameter and the outside too ! There are several other belts like these made by other companies that will also work. They will also be lighter and have as much grip for the same amount of tension. You might not find them in the automotive listings but they can be found in the industrial machine listings.

[Chevy]

i had this prblem on my 68 camaro, you need to put a straight edge across the pulleys and make sure they all line up. Shim with washers to make sure they are perfectly parallel.

Good luck!