So i think this is a belt issue...but here's the deal, and this was not happening yesterday. If i rev the motor while parked, or when I accelerate from a light or stop sign, there is a loud squealing noise...if i am idling, the noise stops. if i let ease up and let go of the gas pedal while driving, the noise stops, and then i hit the gas again, and half the time it does not continue, half the time the noise comes back.
how can i diagnose if this is indeed the belt(s) and what can be done/should be done to stop the noise?
In addition, if it helps..i only have one belt, and it is turning the alternator, fan and drive pulley. Shouldn't there also be an idler pulley, which is what tensions the belt? or is my alternator the tensioning pulley? the drive pulley and fan pulley also seem to have been swapped for billet/chrome ones..photo attached.
Something there's not right or true,
a squealing noise is bad, taboo.
But not to fear, help is near,
At VMF we have a seer.
The solution is (from A to Z),
Just wait to hear from 22GT!
V belts do not typically use a tensioner, that's a serpentine belt thing. V belts are not as sensitive to tension as flat belts, but of course there is a limit. Your setup is exactly correct OEM. The alternator is the tensioner, by loosening the upper and lower bolt you can swing the alternator outward to increase belt tension.
Please note that once a belt starts to slip and squeal it gets a glaze or polished surface on the belt and tightening may not help. At that point you will need to replace the belt.
Just take the belt off & start the engine. If you run it for under a minute no damage will be done.Rev the engine in Park. If the squeal is still there with the belt off you can rule out the alternator & the water pump as the culprits. Then you will have to look further.
Although from your description it seems like the belt is your problem you should 100 percent verify that the noise is/not in the accessory drive - belt and/or accessories (ie alternator, water pump) by removing the belt as suggested by Pony Gaz. If the noise goes away then you need to determine if the issue is in one of the accessories or the belt itself.
If the issue is the belt then there are several things that can cause that including inadequate tension, pulley misalignment, worn belt, or incorrect belt size. For a stock setup your alternator-water pump-crankshaft belt should be 41.2 inches long and 15/32 width (Ford C4TE-8620-S / Motorcraft JB-412). Belt tension can be hard to gauge. When pressed on you should have no more that about 1/2" deflection in the middle of the longest span between pulleys. To check pulley alignment use a long narrow straight edge.
I have the same problem with my 289 hipo with my girl friend in the front seat Squealing to slow down, belt or water pump, buy a new belt put it on throw old one in trunk for emergency spare, still squealing water pump time
Paul hit on all the specifics but one more question.... "Do you have a stock, or a high output alternator?". Have you had your battery load tested. A high-output alternator can drag enough on a v-belt system to cause slippage, especially if it's trying to keep the charge in a weak or failing battery. A water pump with bad bearings can also cause a belt squeal.
I have heard the crankshaft damper can squeal when the rubber is old and cracking. Hard to believe though. Maybe you have a squirrel living under there and it squeals with fear every time you accelerate?
Quote from a web site about failing crankshaft dampers:
"6. The untraceable squeak
A damaged dampener can make a squeak when it rotates, and it will not stop no matter how much belt dressing is applied."
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