GTM Belt sqeal

[fact5racer]

http://www.youtube.com/watch?v=mUereTzgjQg&feature=youtu.be

Man, I can't seem to figure out what's wrong. I don't think it's right for it to jump like that. Any opinions?

[VD2021]

Gary,
Any way we can see the complete belt run? I would suspect flexing somewhere in the system or a bad belt that's stretching.....

[fact5racer]

All there is on this one is the water pump bell, the crank and the alternator and the pulley

[rev2xs]

It looks like the tensioner at the top is screwed. I dont think its supposed to move like that when you rev it, is it? And the really bad sound accompanies that movement.

Do you have Shane's lower pulley support? Very simple yet excellently effective.

http://vraptorspeedworks.com/serpentine-belt-idler-pulley-support/






http://www.youtube.com/watch?v=mUereTzgjQg&feature=youtu.be

Man, I can't seem to figure out what's wrong. I don't think it's right for it to jump like that. Any opinions?

[fact5racer]

But I don't run that lower pulley like most, because once you eliminate the rod shifters, you don't need that clearance in that area. I have never used that lower pulley on my previous cars without any issues.

[65 Cobra Dude]

Gary,

Had the same on my car. The problem was when revved, the tensioner pulley would also move in and out. The simple fix for mine was to make a bracket to support the back of the pulley to the head and the squealing stopped.

Henry

[mikespms]

I sounds like the bearing on the tensioner,check the alignment. If it goes away with belt dressing it could be the belt or a weak tensioner.Try If it goes away with a little wd-40 on the bearing of the tensioner pulley or on the pivot of the tensioner

[VRaptor SpeedWorks, LLC]

It looks like the tensioner at the top is screwed. I dont think its supposed to move like that when you rev it, is it? And the really bad sound accompanies that movement.

Do you have Shane's lower pulley support? Very simple yet excellently effective.

http://vraptorspeedworks.com/serpentine-belt-idler-pulley-support/

Thanks!

[The Stig]

Hi Gary,

Way back when... when it was time to re-assemble the engine components, I remember noticing that the Alternator bracket was slightly bent. I was amazed that I was able to straighten it back out by hand. That didn't seem right to me, so I started looking for alternative fixes.

Based on a suggestion from one of the guys on the ffcars forum, I decided to use the CTS-V Alternator and Bracket. To me, it sounded like a good idea since it provide more strength in how the alternator is attached to the engine. It also used the same alignment path for the belt, so I didn't have to worry about shimming it or adjusting it with fender washers, etc.

I'm also using the lower tensioner between the Alternator and the Water Pump bell to keep the belt in as much contact as possible. (It's part of the CTS-V Alternator Bracket). I was never 100% sure whether or not this would solve the belt squeal issue, until we ran the engine for the first time. It's been run pretty hard on the Dyno, as well as normal idling and revving in the garage, and so far I've not heard any squeal from the belt.

A lot of focus is given to the upper tensioner bracket, (and probably rightfully so) but I think that at high revs that alternator bracket can also flex, just enough to cause the belt to squeal or even jump off.

I don't have the bracket or brace behind my upper tensioner. So I decided that the problem must be due to misalignment when that alt bracket flexes.

It would be worth it to take a look at Shane's fix for that bracket. If I remember right, to buy the CTS-V Alternator, Correct Pig Tail, Bracket, Tensioner, and correct hardware cost me in the neighborhood of $500.00+. (But it seems to be working).

http://i210.photobucket.com/albums/bb94/jmichaelbaskin/DSC_0605-2.jpg

http://i210.photobucket.com/albums/bb94/jmichaelbaskin/DSC_0609.jpg

http://i210.photobucket.com/albums/bb94/jmichaelbaskin/DSC_0608-2.jpg

http://i210.photobucket.com/albums/bb94/jmichaelbaskin/DSC_0611.jpg

[fact5racer]

looks great but expensive. I added a brace to the upper tensioner pulley and so far, so good.