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Squealing noise after underdrive pulley install

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Old Dec 14, 2005 | 12:48 PM
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Default Squealing noise after underdrive pulley install

I had an SLP underdrive pulley installed on my 2000 Formula w/ 48k miles, and after it was put on, a squeaking noise has developed. It didn't start right away, it started maybe a week after I had it put on. Originally, it was only noticeable when the engine was cold, and only when the car was accelerating. Over the past weeks though it has progressed to the point where it can be heard all the time, and it is louder/squeakier than it was before. I've tried spraying belt dressing on it, which quiets it somewhat, but not much, and any benefits that it does get are gone within an hour or so. The belts I had put on were Goodyear Gatorbacks. I did notice right before I had it installed that the crank belt was .5 inch shorter than recommended. I had them put it on anyway, and it fit fine.

Can anyone tell me what this noise might be? Worn tensioner, bad idler pulley, wrong size belt?

Also, can someone give me the proper size (and preferably part number) for the belts to use with the SLP underdrive pulley?
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Old Dec 14, 2005 | 02:11 PM
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i have been reading about underdrive pulleys and it seems there is lot of people that experienced problems with the older style slp pulleys on there car. most of those that had problems talk about squeeking noise as well as false knock that results in the computer pulling timing and further reults in a loss of power. as far as the right belt size you can get the right belts from ttp or other sponsors. hope this helps.
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Old Dec 14, 2005 | 02:24 PM
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I have the newer design SLP pulley, where they supposedly worked out the false knock problems.
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Old Dec 14, 2005 | 08:47 PM
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i have this same problem with an ASP pulley.
its been on the car for 8 months, and it seems to do it worse when its cold as stated above.
if i was my motor, it will do it a lil louder until it warms up.
i thought it was the alternator brushes squeaking, but maybe not.
strange.
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Old Dec 14, 2005 | 10:35 PM
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I fired my car up friday with the new cam/pulley. Ran fine and sounded great. Got it tuned at HPE saturday and the belt started squealing BAD on the dyno. Got home and noticed it wasn't tracking straight on the idler pulley. Removed the belt and found the IDLER pulley was about to fall off. I tightened the bolt, reinstalled the belt, and it started tracking straight and made no noise.

....Just a FREE suggestion lol

Look and see if the pulley is seated all the way. If you look closley, you can look to see if the belt is angled between the crank pulley and the alternator etc. Might need to tighten it more or somthing.

Are you positive that the belt is short enough and the tensioner isnt maxxed out and not applying enough pressure?
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Old Dec 14, 2005 | 10:48 PM
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I have an ASP pulley and the kit came with Gates Micro V belts. The main belt is a K060775 (6PK1969) 21mm x 1980mm, and the A/C belt is a K040410 (4PK1045) 14mm x 1059mm. Hope this helps.
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Old Dec 15, 2005 | 06:14 PM
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i dont have a tensioner at all.
i have a custom mounted alternator bracket with a heim joint and only a 31" belt.
its tight too.

damn cars... its always a noise you cant fix.
grrr.
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Old Dec 18, 2005 | 04:27 PM
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any more ideas?
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Old Dec 18, 2005 | 04:39 PM
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i have a squeeling problem, only when i turn my ac on though. talked to my mechanic brother says that my tensioner pulley has bottomed out cause the belt on it is too big for it to tension. need a smaller belt. only problem is that the belt i need cant be found in houston at the moment, apparently the march pulley set uses a strange size belt. so im waiting on it to come on....
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Old Dec 18, 2005 | 05:47 PM
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try replacing the idler pulley thats what i had to do and after I replaced it no more squeeling, but with moisture and it being cold all pulleys will squeek alittle until its warmed up. there is a good write up on how to change the idler pulley at installuniversity.com.
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