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Hello,

Well....slowly getting there with the engine tuning, and this weekend when I put the carburetor back on it felt much more responsive and aggressive.

But My fan belt is squeeling and won't stop. All the neighbours are staring like my car is garbage.

I have tightened it the best that I can, and I hit it with soap and WD-40 and it's quiet for 20 seconds and then it starts squeeling again...and really loud too.

All my pullies are straight and it's a new belt this summer.

Anyone ever have this problem?

Thanks, Greg.
 

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If you are sure the pulleys are aligned, you need to check the water pump and the alternator. I suspect the bearings in one of them may be failing. You can remove the belt and spin the pulleys of each by hand, but this often does not help. It is only with the load of the tight belt that the bearing will make noise or bind.

You could remove the alternator and have it tested at a local shop. Since it is mounted to machine and driven with a belt the noise may appear.

Another method that you could try would be to use a stethoscope. There are ones made specifically for tracking down noises like this. They have a special adapter which allows you to pinpoint a small area.
 

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I am in the process of shimming one of my pullies on my 73 convertible. It too is squealing under load. At idle it is fine. In my experience, squealing is usually an indication that the bearing is under stress or is about to go. I would suggest adjusting the fan belt (a little more loose at first - perhaps a 3/4 inch deflection when you push it in with a straight edge betwen the pullies). If it is still squealing, it isn't likely the fan belt causing the problem, it would be something out of alignment putting stress on the belt. The wd 40 may be working momentarily, by masking the load the belt is turning under, and therefore quiets down briefly. Too tight a fan belt will wear out your bearings. Check the pulleys to make sure they are perfectly aligned, and if necessary shim the pulleys. Have someone put the car in gear and check to see if the squealing increases when the car is under load. As a final thought, are you sure you have the correct fan belt (length and depth for the pulleys)

gord
 

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If the squeeling stopped with the application of soap and WD-40 on the belt, for a few moments, the belt must be the cause of the noise. Since the squeek came back the belt or pulleys are at fault. Try a new belt after carefully wiping the grooves with lacquer thinner and then sanding the grooves with 220/300 paper.

Let us know what works. Good luck.

Mark Mosteller
Garden Grove, CA
 

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If the belt is too narrow it will "bottom out" on the base of the pulley groove and will squeal no matter what you do (because the pressure is not on the sides of the belt). A lot of cheap v-belts are made narrower than the factory ones.
 

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What are the good brands of belts, and where do you get them? I have a problem with the Dayco (?) (Day-something) belts on my kids' '65 289. No PS, no AC. I tighten the belt and the squealing stops for a few thousand miles, then returns. I am on my third re-tightening and I too am worried about the alternator and water pump wearing out from too tight a belt.

7
 

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Your local Auto Zone, Carquest, NAPA, what ever chain store is your area should be able to match you up. I got both my new ones at the Zone, and the alt belt squealed till I tightned it down real good. Now no problem what so ever.
William :p
 

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Sure its not the alternator bearing??? Mine make a ear piercing shriek when you really get on the gas.
 

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I agree with the others that it could be an alternator bearing. I just went through this recently and that was the cause. I also will throw out there that if you have upgraded your alternator, there is a chance that the pulley on that one is designed for a 17mm belt whereas the crank and water pump pulleys on the early SBF are 15mm belt size. This is the case with my powermaster, as they feel the higher amp output requires a thicker belt. However, since the other pulleys on my car are 15mm, it isn't practical to run a 17mm on it, so the alternator shop said that I would just have to run the belt pretty tight to get it to sit into the alternator pulley farther. The guy did say that this would not be good for belt life, but I am not that concerned about having to change a belt a little more often.

Dave
 
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