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Serpentine Belt & Bon-Ami

Last week I had a mechanice replace an alternator-belt in my '95 Saturn SL2. It didn’t fix the screeching noise that my serpentine-belt was making - in fact, it may’ve made it worse? It now takes twice as long for the screech to go away. I’m thinking about using Bon-Ami (if it’s still around) or Comet, etc. to determine which belt is making the horrific screech. Is this a viable solution? Also, how long is reasonable for me to use a cleanser on a belt? Thanks a lot!

How many belts are there, and how many did the mechanic replace?

That’s a new one on me. The last thing I’d want to put on my engine’s rotating parts is an abrasive. Is the alternator belt different than the serpentine belt? It could be a bearing, hopefully on the idler pully and not the alternator.

answered on Saturdays show, better off changing belt.

The new belt is slightly too long


Something is binding for the first few minutes that still needs fixed.

On a car that age it could be anything with a bearing.
With the belt off, test spin everything cold. Some things may not spin due to their compression nature like the p/s pump, the crankshaft, and the a/c compressor. The a/c clutch will spin freely when not cued to be on.

The Bon-Ami trick has been around as long as Coca Cola on the windshield to remove road grime and pepper in the radiator to fix leaks. Some of the methods actually worked but it’s best to avoid things like that and to use proven methods of auto repair.

Note: most of the BonAmi around today is in the Gold can. The original version comes in a Yellow can. The Yellow can is what got the name (It’s never scratched) The new stuff can. Keep that in mind. I don’t want abrasive stuff around or in my engine.

A weak belt tensioner, dragging tensioner or idler bearing, or a worn pulley can cause this and I agree that you should skip the abrasives or it could lead to a situation like below. Maybe Bon-Ami was the cause of this. I’ll never know.

A few years ago I replaced an alternator on one of my cars with a Reman unit. After a few minutes the alternator was not charging, idiot light on, etc. (new belt and tensioner too)
The problem was a worn serpentine pulley on the alternator. It was near impossible to determine this with the naked eye and another alternator cured the problem.

In this case, the new belt would flat not get a bite on the alternator pulley. With the belt in place one could easily spin the alternator pulley with a socket/ratchet.