Underdrive Pulley/belt issue update..,

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onequiksc

Registered User
The news after my other post regarding the belt alignment with my alternator underive pulley, is that things got worse, even though I thought it was working out ok (got the belt riding better but that did not last). Shredded 2 ribs off my second serpentine belt, the pulley CLEARLY sticks out from about 3/16th to 1/4" more than the other pulleys in the belt loop...I spoke to Bryan and he noticed far too many alt shaft threads were sticking out from the nut in my pics, and that the clearance between the alt casing and the backside of the underdrive pulley Bill E sold me was way too much, as his stock pulley had about 1/16th in the same spot..he suspected there was a spacer behind it pushing it forward...he was right...but it gets worse.

Bryan came over today and helped me remove the underdrive pulley, and we indeed found the spacer pictured below was behind it. Problem is, the spacer moves the pulley too far out of position (forward) and if we take the spacer out, the underdrive pulley rubs on the front casing of the alt. It needs a spacer for sure, just NOT that one!

That cannot be the right spacer for this application, period.

Bill sold me these as "used" but I expected they would fit my application regardless, as he knew what it was going on.

Now I'm in a position where I either have to;

1) find the proper spacer for that pulley, if Bill even knows what the proper size is (I assume he knew the manufacturer, at least I hope so)

2) Have the spacer cut to proper size by a machine shop, or have them make one to specs, only I don't know the specs necessary or if a shop can figure it out based on the oem pulley setback.

I tried calling Bill yesterday but got his voice mail, will call again tomorrow...

Gone through 2 belts now, one a Gatorback, so it's getting expensive.

comments / advice?

Underdrive with spacer on it vs smaller oem pulley w/o spacer;



Underdrive pulley with spacer off vs oem pulley;



backsides of underdrive vs oem;

 
Originally the early model SC's alternator pulley had the shallow back spacing as shown on the UD pulley you show. Late model SC's had more backspacing and required a different pulley. This was never addressed with the ASP UD kit that you have. March addressed this issue with a super shallow backspacing pulley and then two different spacers so that you could select the one you need.

The spacer you show is from a March kit and doesn't work with the ASP pulleys you have.

The situation has been further complicated over the years by the fact that the aftermarket rebuilders have mixed up the alternators so when you buy a replacment alternator, you no longer have any idea what you are getting. They supply the right pulley to do with the alternator, but it may not be the exact combo you had before. Because these cars are so old, it is impossible to know if your alternator has been replaced, and what alternator it might have been replaced with so it's become a crap shoot what you have on what year unless you have owned the car since new and know exactly what is on it.

Your solution is not going to be easy. I think that if you make the exact size spacer needed to align the pulley you will find that it rubs on the alternator case. You may have to clearance the front of the alternator case to run that pulley. I have dealt with this many times. Might be better just to use the stock alternator pulley.
 
Thx Dave, that's more insight than I expected...though not good news.

The alt is only the 2nd one the car has ever had, and it was a Motorcraft oem alt replacement from Ford.

What gripes me most about this, is people selling stuff to make $$$ without regard or even mentioning the issues one may have. It bugged me at first that my shop gave me back the car with such an obvious misalignment, but he probably tried it w/o the spacer and found it wouldn't work at all...

As for going back to the oem pulley, well sure, but the problem there is...what belt to use if there even is one made to run with crank & water pump underdrives and oem alt pulley...

...basically, I think I'm screwed and I don't see a pretty blond on my lap...
 
onequiksc said:
Thx Dave, that's more insight than I expected...though not good news.

The alt is only the 2nd one the car has ever had, and it was a Motorcraft oem alt replacement from Ford.

What gripes me most about this, is people selling stuff to make $$$ without regard or even mentioning the issues one may have. It bugged me at first that my shop gave me back the car with such an obvious misalignment, but he probably tried it w/o the spacer and found it wouldn't work at all...

As for going back to the oem pulley, well sure, but the problem there is...what belt to use if there even is one made to run with crank & water pump underdrives and oem alt pulley...

...basically, I think I'm screwed and I don't see a pretty blond on my lap...
Click to expand...

Just use the stock belt. It will work out.
 
It will?

Am I thinking about the pulley size difference backwards?...I thought going back to the smaller diameter pulley would make it tighter where the belts meet at the water pump pulley...An extra inch or more of belt won't make that near touching of the belts even more so?
 
Dan,

I don't have ASP underdrive pulleys on my car right now, but I had them on there since 1994. I don't remember the ASPs coming with a spacer and they worked just fine. Although I might have bought the set before they realized (like March) that there is a difference between late and early model alternators.

Anyway, have you tried stacking a couple of metric washers? The OD on metric washers is typically smaller than standard washers. I'd try finding something at the local hardware store before giving up on the pulley.

Kurt
 
Dan.... I may be able to turn the spacer down with a small lathe my brother has. I assume the spacer is just anodized steel which should be no problem. If it is hardened steel no can do then.

Bryan
 
Thanks Kurt, that's interesting info...I'll talk with Bryan on that one...

Bry, will talk with you this week, if all other options fail, I'm leaning towards just getting that oem pulley from you (for the rest of you guys-the reason my oem pulley is out is because the tech at the shop fubarred it up taking it off...Bryan has offered me one he has) and be done with it...That is, if Dave's correct on using a stock belt, I think there's less risk of going through belts faster than one should.

Got to say, Bryan is ALWAYS there when an SCer needs help, can't say enough about the man. He offered to come help, and he sure did, w/o his idea of taking the alt out of the car and putting an impact on the nut, that thing wasn't coming off, believe me I tried.

My regards Bry, as always. And to Dave for the solid info. :)
 
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Kurt K said:
Dan,

I don't have ASP underdrive pulleys on my car right now, but I had them on there since 1994. I don't remember the ASPs coming with a spacer and they worked just fine.
Click to expand...

That's because your car is a 92, ie. early model.
 
Just to update everyone, I had a machine shop reduce the size of the spacer bushing perfectly and everything lines up great now. Also got the 893 length belt from Napa and I'm real good as far as clearance near the water pump pulley/ main tension-er pulley (can fit a finger in the gap now).

With all that behind me, now it's time for some new strut rod to front cross-member bushings, then I can drive it with more confidence.

Thanks for all the help guys, until the next catastrophe....:)
 
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