View Full Version : Belt Idler Pulley Question

05-03-06, 09:17 PM
Here's an easy question for seasoned Fleetwood owners: How long does the serpentine belt idler pulley last? (It looks so cheap and flimsy.) I'm assuming that the pulley on my 93 Fleetwood is original. With 154,000 miles on the clock, do you think it's time to replace it? How much does it cost and what are some of the problems/issues encountered when replacing it? Thanks.

05-03-06, 11:27 PM
Get yourself a belt tension gauge and check it.

Find out what the belt tension is supposed to be and see if yours is still within specs.

05-04-06, 09:35 AM
Check it for any cracks or tearing or pulling. It's a cheap part, I paid I think perhaps $30 for the nice one, it's a Goodyear Silent or something like that, I can't remember, but replacing it is laughably simple. The routing is on a sticker under the hood, just like the emissions sticker.

05-04-06, 10:44 AM
My 96 Suburban went 210K on stock one. They last a long while. If they start sqealing, then replace them. Mine started sqealing and in a thousand miles or so seized and melted the belt.

05-04-06, 10:56 AM
Sounds good, thanks. I was just curious if the idler pulley gave any advance notice of imminent bearing failure or if it simply siezed up and shredded the belt. I suppose I'll wait for the squeal, then R & R within 1000 miles unless I happen across an extra $30 in my wallet before then.

05-04-06, 10:59 AM
On mine, the pulley was $50 with bearing, bearing only $10. And very easy to swap. I just put the pulley in a vise (not hard, just to stabiltize) and then hammered out with a socket on the edges of the bearing and tapped in new one same direction. Took all of 15 min, start to finish on the whole project.

Pretty much if it is quiet, drive normally. If it is noisy, then consider worrying, it will get worse before it fails. These are sealed bearings and they live a LONG time.

My 94 LT1 is on factory ones from what I can tell. I haven't noticed any repairs for them in the records, but I wasn't looking specifically for that.

The Ape Man
05-05-06, 01:37 PM
The idler pulley itself can last a good long time if it was a good bearing to begin with. Some replacement bearings have a little tin shield instead of a seal. These do not last unless used with a fresh supply of lubricant. If the car was taken to a chain repair place where the "technicians" make their $ selling easy to replace stuff then it might have changed to a cheapie type. Always look for an Orange seal and not a metal shield with a few slots. BTW, same bearing was used as an alternator shaft bearing in many GM cars.
Now, if we are speaking of a belt tensioner there are 3 failures. 1st is the bearing. These can fail without ANY NOISE so don't write it off as good without a check. With the belt off, give the pulley a spin. If it is loose of feels anything but smooth it is worn.
2nd failure is the spring in the tensioner. The thing may bounce all over the place with the engine running when the spring wears out. This spring sets the belt tension. If certain accessories like the alternator squeel under high loads with a fresh dry (no oil leaks) fan belt then suspect a wimpy tensioner.
3rd is a worn out pivot. A worn out pivot allows the tensioner pulley itself to move at a slight angle to it's proper plane. This will show up with the belt riding on 1 edge of the pulley. Any indication of fraying on one side of the slurpentine belt is a hint to look for a bad tensioner pivot. After a while the belt will fly off. Tensioners can be examined for rust near the pivot spring area. The bad ones sometimes give away their condition with a nice little rust trail.
Most belt tensioners are a cake walk to replace.

05-08-06, 10:23 AM
Thanks for the information. Both pulleys must contain excellent quality bearings. Interesting about the alternator pulley bearing, too. It seems worthwhile to replace the idler pulley bearing sometime in the 150,000-200,000 mile range before it has the opportunity to sieze and shred the serpentine belt.