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mdskier
07-21-2009, 03:02 PM
The belt was squealing on my '99 Maristar so I replaced it. Seemed fine for an hour or 2 and then started squealing again.

When replacing it I noticed that the idler pulley spring was not very "tight". I checked the bearings on it and they were fine. The pump was new last year and the alternator seemed to spin fine.

I have to take a look at it again now that it is squealing but the belt I took off was worn on the back side only for a about 1/4" from the edge. The idler pulley seemed to have some peeling paint and possibly rust.

Anyone had to replace that pulley and/or the spring mechanism before?

Thanks.

-tom

Jerseydave
07-21-2009, 03:32 PM
Might be a good idea to replace your 10-year-old tensioner and pulley. Rust on the pulley will shorten the belt's life pretty quickly.

Where in MD do you ski?

babymoore3
07-21-2009, 06:03 PM
Serpentine belts are VERY sensitive to misalignment, that is why the automotive shops replace tensioners with belts most times. IF that doesn't check out maybe you have a bent pulley or incorrect spacing somewhere or the maybe belt is slipping? Does everything turn freely when the belt is not installed, is tensioner (weak spring) not holding belt on tight enough?

A decent elaboration on serpentines...

http://www.cartechbooks.com/vstore/showdetl.cfm?st=0&st2=0&st3=0&CATID=21&Product_ID=3656&DID=6

http://www.popularmechanics.com/how_to_central/automotive/1272561.html?page=1

mdskier
07-21-2009, 07:56 PM
Thanks.

Everything does turn freely without the belt on. I think it is the tensioner worn out. I will check the local dealer to see if they can get me a tensioner quickly.

I am at Deep Creek Lake in western Maryland, njskier.

TMCNo1
07-21-2009, 08:16 PM
Could it be the belt had been replaced previously with a larger belt, causing it to slip?

mdskier
07-21-2009, 08:46 PM
No, I don't think so. I bought a new belt from Skidim and it is the same size as the one I took off.

I don't know exactly what a proper tensioner feels like, but I think from what I could tell the one I have has a weak spring and it probably is not giving enough tension. One of the links from BabyMoore3 explains the problem pretty well.

JimN
07-21-2009, 08:51 PM
No, I don't think so. I bought a new belt from Skidim and it is the same size as the one I took off.

I don't know exactly what a proper tensioner feels like, but I think from what I could tell the one I have has a weak spring and it probably is not giving enough tension. One of the links from BabyMoore3 explains the problem pretty well.

Tensioners do lose spring tension over time and replacing it is probably needed. Do you have a torque wrench with low foot-pound increments? Measuring it for how much torque is needed to rotate it 45-60 might be a good way to find out if it's weak.

mdskier
07-23-2009, 08:36 PM
Just to close the loop, $60 and a new tensioner later resolved the issue. The tensioner was definitely gone. The old one had no consistent tension on the belt. Installing the new one showed me how it should have felt and I realized the spring mechanism was shot in the old one.

Thanks for the responses.

JimN
07-23-2009, 09:01 PM
Just to close the loop, $60 and a new tensioner later resolved the issue. The tensioner was definitely gone. The old one had no consistent tension on the belt. Installing the new one showed me how it should have felt and I realized the spring mechanism was shot in the old one.

Thanks for the responses.

Cool. I was going through a belt about every 9 months on my Chevy pickup and then, the plastic pulley's bearing froze, so I had to replace it. Huge difference in tension and the next belt lasted more than a year, until it got full of coolant and started to separate.