I'm not exactly new to this type of job, just new to the job on the Disco... So a few weeks ago the squealing under the hood started to get really annoying. Did some investigating and decided to replace all the idler pulleys and the tensioner assembly. While I was at it, since the truck came with a new Micro-V belt when I bought it at auction, I decided to just replace it too since the other was showing some cracks in the ribs.

Anyways, I got it all back together but everytime I start the truck, the belt jumps onto the edge of the tensioner pulley and starts to roll off the edge of the lower idler pulley below it. I can loosen the tensioner, straighten the belt out, and still it jumps off as soon as starting the truck. I kept the old parts and as far as I can figure, maybe the tensioner is out of alignment, maybe the pulley too? Is the pulley supposed to have some sort of spacer behind it? I didn't see any. I a have taken care to make sure the located is properly seated too. Also, I put on the old tensioner just in case the old would get me through a few more weeks (new one could be bad...)

I took pictures...





Any guidance will do, thanks.

 

If the bearing in a plastic pulley overheats, melts/deforms the plastic and misaligns it.

The steering pump shaft can slide outwards by itself and misalign its pulley. If that is the case, lighly tap it inwards with a hammer.
Good light and a sharp eye should find where is the trouble.

 

Is the old tensioner squeaking?

 

check your crank pulley too to ensure that the rubber dampener material surrounding the perimeter is in good shape. mine got crusty and was missing
chunks and this was causing it to wobble and throw the belt off a rib. they ain't cheap either.

 

In photos, the idler pulley (smooth one) looks crooked, not in plane with other pulleys.

FWIW, there is an on-line outfit that will renew the silicon in the crank pulley (remove old, pour in new stuff). I have not needed that service, but the price is reasonable.

 

JohnZo, can you direct me to a contact for the crank pulley refurbishment outfit?

 

Two online outfits I looked at Damper Doctor (Redding CA) and Steele Rubber Products (Denver NC). $240 to Steele refurbs dampers from 1958 Oldsmobile, so might be a match. Don't know if they will work on ours.