I put some washers between the underdrive pulley today and that straightened out the belt track seemingly just fine..
So I drove it around the block and it drove just fine. Popped the hood and the belt seemed fine and not jumping around but I did notice my amps gauge studdering a little meaning maybe the belt is a little too loose or something..But I think it is pretty darn straight..so ...
I took it for a forty mile run tonight..but I noticed a flapping sound on the bway and it did not sound normal, no I nursed it back to my house to find my temps going up, power sterring going out and my battery light coming on..![]()
So when I got it in the driveway just b4 overheating, I popped the hood and noticed the belt was torn to shreads...![]()
I know after the car is warmed up, I can pull the belt off the tensioner pulley by hand.
I can only guess that it is a little too loose and when the car heated up it became more loose and jumped then tore itself up[/B]?![]()
Does this make sense to anyone as a possibility? I want to try to nail it down so I don't start spending tons of money on belts..
So I am going to try Mike's suggestion of getting an idler pulley in place of the tensioner pulley to tighten some slack up.
Also, when I try to sping the idler it turns but does not SPIN, like the bearings are a little worn.. same with the tensioner pulley.. Is theis NORMAL?![]()
Could this cause a belt to JUMP?![]()
Are they a different size and are they really interchangeable?
I just caught your post Mike. Yes, I tried to find an 84.5 but they don't seem to make one..or not at salvo..does anyone know if they make that size? I was going to get the idlers from 5.0 resto..
Oh, .. also, you have a mack underdrive, stock water pump and mac alt pulley right? I have a rebuilt alt with what looks like a larger pulley than stock alt, frpp water pump underdrive and frpp crank under drive..
I am wondering if it would be smarter to just match someone like your setup and know for sure I won't go thru 9 $36 belts..


My belt would "walk" off the pulleys after two mintues of driving when I got rid of ac and smog. Turned out that the PS pulley wasn't seated all the way.
I don't think the 1/2" shorter belt is going to be the fix, I'd bet one of your pulley's is not in line with the rest.
Thanks everyone. hmm..., how do you seat it? Is that those 3 bolts?
I tested it at higher rpm's sitting. It stayed on..I am thinking the belt gets loose as the car/belt heats up b/c I don't see anything out of algnment. I will rechck again.
Mike thanks for the pics.
On the ques of the crank bolt, it is tight. I put the shims in to line up the under drive crank pulley even with the others.
