
Originally Posted by
plugma
I have discovered that there is more to belt maintenence than the book says!
The local L/R mechanic told me that if you have checked everything else including tensioner, cleaning out grooves, new belt and the squeek aint gone.... it's more than likely the alternator pulley. He tells me that because of the constant drive pressure, the pulley wears and the the belt tends to ride higher in the pulley which causes the squeaking. His remedy is to take the alternator out... spin it up with a cordless drill and re-file the grooves. Exactly how that's done i'm not sure!
Speaking of grooves... the best indicator of dirt in them is movement of the tensioner. If the tensioner moves up and down at all, it's more than likely crud build up in the pulley/idler grooves.
Had exactly that problem this week when replacing the belt. I spent a good hour with a wire brush cleaning out all the grooves untill they looked really clean. After replacing the belt, I still had the problem of the tensioner bobbing up and down. I removed the belt and took to the grooves with a sharpened right angle metal scribe. Amazing how much really hard black stuff came out!! Replaced belt and... problem solved... or at least that part of it.
It still sqeaked!!!
I put a metal rule across the front of the water pump pulley and extended it over the tensioner pulley, then carefully measured the distance between the rule and the front edge of the tensioner pulley. The measurement from one side to the other was not the same, indicating that the tensioner was out of line with the passenger side closer to the front than the other side.
Carefull inspection of the removed tensioner showed that it had worn the thin layer of plastic between the two main parts and that some of it had in fact come out on the underneath side. It was also clear that the two parts were no longer parrallel to one another with no gap on one side and around 1mm on the other.
Whilst re-positioning the old tensioner, I placed a number of shims behind it on the drivers side before bolting it down. I replaced the belt and.... no more squeaks!
I think what happens is... as the tensioner wears it moves forward on one side and skews. This drives the belt forward into the front edge of the water pump pulley which causes the squeak. It could also be caused by the belt tracking at a slight angle over the tensioner pulley.
New tensioner is on order from Coventry Motors for $105.
Hope the above adds to the knowledge base in our never ending quest to stop the damn squeak!
Regards
M.
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