Help needed

onequiksc

Registered User
Had my shop put underdrives ( bought from Bill E) on crank, waterpump and Alt, and the shop showed me the main serpentine belt was so close it was almost touching itself near the water pump pully/ main ( top)tensioner...Looked about 1/8th or less to me. Bill says on his site that contrary to claims, the underdrives "do NOT require a different size belt". I guess my car doesn't agree.

Asked the shop to source a smaller belt and they said it was crazy; they were all about 8 or 9 numbers off, nothing came close enough...

I drove it home and a couple times since, all was ok, till today when I went to move it from the driveway to the garage,...something gave a bit and they are touching, and I've already shredded the belt edge off within seconds.

I've read about others mentioning this close tolerance after underdrive pullys install, but has this happened to anyone else? What did they do to solve it?

Shop said they would check into different size belts again but doesn't sound promising...
 
Sc

Update; I had the old (smaller) plastic SC tensioner pully laying around, and swapped it out onto the main tensioner, now I have about 3/8'' clearance,

Good right?...well, now I have another issue that may have been there and went unnoticed; the belt is riding on the alt/ pully inside lip, out of alignment. I can pop it back on the pully correctly, but as soon as I start the car it rides back up on the inside pully lip...appears the alternator underdrive sticks out about 1/8th farther than the rest of the serpentine beltway...~~~?

And here I thought underdrives were such a win/win...
 
Update; I had the old (smaller) plastic SC tensioner pully laying around, and swapped it out onto the main tensioner, now I have about 3/8'' clearance,

Good right?...well, now I have another issue that may have been there and went unnoticed; the belt is riding on the alt/ pully inside lip, out of alignment. I can pop it back on the pully correctly, but as soon as I start the car it rides back up on the inside pully lip...appears the alternator underdrive sticks out about 1/8th farther than the rest of the serpentine beltway...~~~?

And here I thought underdrives were such a win/win...

I know that some alternator pulleys require a spacer. Could it be that a spacer was left on the alternator?

If that is not the case, could you put some washers behind the alternator bracket to shim it into alignment?
 
Can you grab a photo of the alt. pulley?

Did you notice if the hub was offset and maybe it is installed inside/out?

But yes, check for an unneeded spacer as noted...
 
Thanks fellas, i was about to take a pic, but here's an update;

Now I've run it a few times, and oddly, the belt is currently running on the pulley correctly, revved it and all seems ok....don't know what that was about. I will need to replace the belt with a new one anyway, so I'll run it a while and if it starts to wear I'll dig into fixing the situation before I put the new belt on.

BTW...The Gatorback belt that got shredded is off, and I put an old oem belt on that I had (mostly worn out)...but it was kind of stiff from sitting around for years, so perhaps it needed to work in?

Ahhh..I'm just throwing s##% out there hoping something makes some sense.

And lastly, it appears I will also have to put a shim in between the upper intercooler tube to IC bracket and alternator as the underdrive alt pulley, now bigger than the stock one, has about 1/16th clearance between the pulley and the upper IC tube bracket...it's too damn close. All it will take is some large amount of engine torqueing to hit the bracket, ...I know the IC tubes & IC moves with the engine but does it move enough for that small amount of clearance? THAT is the question I suppose.

The hits just keep on comin'...Did I mention I love these underdrives?

Will take a photo of the current alt pulley/ IC tube bracket clearance issue if I can't resolve it otherwise...

Thanks again for the speedy responses...
 
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It may be that the Gatorback belt that was on the car when I took it home from the shop ( and was shredding today when this all started), was riding correctly on the alt pulley (I really tend to notice things fairly quickly and I think I would have caught that..., though I am fallible!) but the oem belt I put on after I added the smaller SC pulley to the main tensioner was pretty stiff and hard...

Hopefully running it a while will prove things are ok as far as the alignment goes...

The last issue remains however...
 
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Clearance issue between upper IC tube to IC bracket and alt pulley, about 1/16th". I was thinking I could get some extra piece of mind if I remove the bracket and grind it down a little, just don't want to weaken it, but I wouldn't need to remove much...








Belt riding ok now on alt pulley...I don't *think* that's a washer/shim behind it but rather the mating hub of the pulley...all I really need to do is stop by the shop tomorrow and ask the tech...

BTW...the time stamps are not accurate, got to get into my camera and update the date...

 
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Dan,
Nothing a little grinding won't take care of :D Loosen the IC flange, rotate it, hold with vice grips & grind a little clerance in it.
Glenn
 
...but I wouldn't need to remove much...

I was going to say enough to be able to remove the belt, but stock gap is approx. 7/16", at least on my car, and at that the belt needs to be fiddled just a bit to come out…not sure the clamp has that much to lose?

Maybe just clearance it (once you're confident the pulley is aligned) enough for running and plan on removing the IC clamp should the belt need to be removed.
 
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Dan, if my car wasn't on the lift, I'd take a picture of how I ground my IC tube flange. As suggested, you will definitely want to clearance enough to be able to swap the belt without removing the flange every time. I've also found it is possible to orientate the flange a bit when mounting to gain a bit of room too.
 
Thx Kurt, I managed to find a simpler alternative that seems to work, a 3/4" wide piece of hard plastic wedged between the upper IC tube and alternator pulled it apart enough to give me about 3/8 " (close to 1/2" actually) clearance now...

Took the car for a ride and all seems well.

I just need to order a new oem belt, though I may check into a shorter belt from Summit (item # GTR4080872) that someone here ordered to address the same issue, though he said in his post he'd report back on how it worked when he received it, and he never did post that follow-up. He had tried quite a few sizes and thought that one was going to be the correct smaller belt, according to his research on sizes.

I also want to order 3 plastic Gates tensioner pulleys (Bryan mentioned them when I saw him in New Smyrna recently, as he has them on his car). I'll get 2 of the smaller SC tensioner pulley size (since that's what is giving me the clearance now on the main belt) and 1 for the jackshaft in the larger size.

After that, onto the next problem that arises...and they always will on a car that has near 300k :)
 
Dan the part number for the Gates pulley is 38023. They should run you about $18.00 give or take. I found the pulley on Ebay for $16.04 each. Unfortunately the pulley is the larger diameter only. Haven't been able to find the smaller SC tensioner pulley. I just use the same larger pulley for all 3 tensioners.

Good luck and let me know if you need anything.

Bryan
 
Dan the part number for the Gates pulley is 38023. They should run you about $18.00 give or take. I found the pulley on Ebay for $16.04 each. Unfortunately the pulley is the larger diameter only. Haven't been able to find the smaller SC tensioner pulley. I just use the same larger pulley for all 3 tensioners.

Good luck and let me know if you need anything.

Bryan

Can't beat a $20 fix. :)
 
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