Belt is screeching again

I've had this sympton on my '95 SW2 for years. The belt squeals sometimes for a few seconds after first starting the engine. I've changed the belt and pulled off the pulleys to check the bearings. I've concluded it's a weak tensioner. (I figure the extra load from the alternator recharging the battery after starting causes some belt slippage.) Still not sure if I'm gonna bother replacing the tensioner. The part is not real expensive, but the job is a little bit of a pain due to limited working room.

I've seen other posts here about weak tensioners and how they should be replaced. Also worth if you have to take off the belt, to inspect all the grooves that they are clean and free of any compacted crud. If the belt can't seat all the way into the groove, it will slip. You are correct about the alternator load on startup. It is sometimes worse when the alternator has been replaced with a heavier duty unit which has a higher torque load. When the system is charging, the highest torqe load from the alternator is at idle. Oppie

Sounds like a good cause for the slipping.

You have that right. It would be nice if a fender well panel could be removed for easy access. Thanks for the input. MR

I would recommend replacing the tensioner. And I would do it before it comes apart while you are out on the road. My buddy is a parts guy at Saturn and he claims they see them come apart and will leave you stranded. Replace the tensioner on your terms and schedule, not your cars! I have replaced mine twice in 120K, so yours must be living on borrowed time.

James

Is it the whole tensioner or just the pulley that fails or both? The pulley looks as if it would be pretty easy to change, but the tensioner looks to be a real bitch to change out. Thanks, MR

The tensioner is fastened to the motor with 2 bolts if I recall correctly. Remove the inner wheel well liner, and access it will provide should allow you to swap it without too much fuss.

Lane [ lane (at) evilplastic.com ]

After getting into it, I noticed that the tensioner, and idler pulley that mounts on center of engine need replacing. The idler pulley is worn where the belt contacts and grease has come out of the bearing and caked on seals. Also, tensioner is shot and pulley on it is worn also. I am in the middle of removing the tensioner now(ran out of time last nite). It is a tough place to work with large hands even thru the wheel well. The new tensioner came with a poly pulley instead of metal. Sure hope it holds up as well as the metal one. It should as it cost $58. Thanks for the all the info from the group. MR

Working thru the wheel housing is the easiest, but one bolt is still a pain, but not impossible. If I recall correctly, I used a u-joint or wobble extention.

Replace both the tensioner and the idler pulley if you suspect both are bad or high milage. The tensioner will have the pulley already attached.

It is the top bolt on the tensioner that was a pain to get out and in due to pwr. steering pulley, but finnally finished it using a few sockets, wrenches etc.

Right on. I replaced both as they had both lost the grease out of the bearings and had a groove worn in the pulleys from the back of belt contact and possibly pulley drag. I suspect that the pulleys were right at the point of self destructing and will check to see if the drag from them was causing a drop in gas mileage. Thanks again for the info. MR

Had this problem with one of my other cars. The belt tensioner bearing was worn out. It made a schreeching sound you wouldn't believe! I think you will be better off replacing the tensioner pulley/bearing/spring assembly.

I did. Replaced tensioner, which came as an ass'y. with pulley. And I might add, had a poly material for pulley. It was a Dayco brand and made in US. Also replaced the idler pulley which was shot. Not only gained peace of mind, but got the gas mileage back to what it should be. I would not have thought that the bad pulleys could have had that much of an effect on mpg. I must say though, that it was a bitch of a job, but worth it. MR