Fan belts squealing - can’t seem to solve

[AR67GTX]

Well, that was short lived - about 10-12 miles - and then back to squealing. I’ll pull the belt off and soap it down and try to rig up something better to sand the groove on the lower pulley.

 

[68gtxman]

Well, that was short lived - about 10-12 miles - and then back to squealing. I’ll pull the belt off and soap it down and try to rig up something better to sand the groove on the lower pulley.

My 1968 GTX with AC has belts squeals because I don’t have the 1968 power steering pump brackets on it (I have the 1969 version). I have the correct brackets now, but not installed due to a rod knock that developed a few years ago. Good luck with your issue!

 

[themechanic]

I have the same belt setup on my 67 383 with PS and A/C. I had to replace the idler pulley several years ago because it started making a noise that sounded a lot like a belt squealing. Checking the belts, I noticed that the idler did not turn smoothly - the bearings were going bad.

Was it rpm sensitive as mentioned above or a constant squeal?

 

[Unkle Krusty]

The belt on my boat was squealing. Had to tighten it too much to stop the noise. New made in China belts, two of them. Put on a used made in USA and the noise stopped.
I suspect the belt quality is a problem.

 

[themechanic]

Many years ago I had access to free powder coating and everything went to the powder coaters including the crank and water pump pulleys. Man did they squeek.....

That is probably the source of my belt squeal. All new pulleys from Bouchillon Performance Engineering are powder coated. Only squeals above 2300 RPM.

 

[hunt2elk]

Any chance your belts are Gates? Reason I ask, is a few years ago I went trough the same deal. I had bought Gates belts all my life thinking they were the best. Never a problem until a few years ago. I think I tried 8 different Gates from different sellers and they all squealed. Ended up trying some Oreilly house brand, and they were perfectly quiet. Been using that brand ever since.

 

[AR67GTX]

Was it rpm sensitive as mentioned above or a constant squeal?

It starts when the rpm’s get into the 2500-3000 rpm range with moderate acceleration. Cruising at 55-60 at steady throttle it’s quiet - not sure about higher speed. Cruising along at 25 - 35 mph in drive I can just goose the throttle and it squeals. I have a looser than stock converter so the rpm’s are probably flashing to 2500+ rpm’s when I do it.

 

[AR67GTX]

My 1968 GTX with AC has belts squeals because I don’t have the 1968 power steering pump brackets on it (I have the 1969 version). I have the correct brackets now, but not installed due to a rod knock that developed a few years ago. Good luck with your issue!
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Buying someone else’s semi-restored (rebuilt better term) car is so much fun. After owning for 20 years I realized the lower brace from the alternator to the idler pulley mount was missing. So I bought that and installed thinking it might help - but not. And then last year I realized the rear part of my Federal PS pump was missing and just the front bracket piece was mounting it. So I bought a new reproduction mount installed hoping it might help in some way - but again, no bueno.