This vexes me...
Thread Starter
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Tuned
Joined: Jun 2015
Posts: 354
Likes: 8
From: Winchester, KY,USA
This vexes me...
I am totally vexed!!! Ever since I finished my 351 swap, I have had this belt squeal problem. I have new idler and tensioner pulleys, smog pump eliminator pulley, new water pump, new power steering pump and pulley, plus a new belt. When I start the engine, the belt screeches and the alternator doesn't show a charge. It'll read 10.2 volts. Now I can pull the alternator plug and the screech goes away. Or I can use my battery charger and while the engine is running, move the selector switch up two clicks from 2 amps/trickle charge to 40 amps and the belt screeching stops and the voltmeter will read 14.6 volts. I have replaced the alternator three times(new units, not reman) and this time I even tried replacing the voltage regulator to a soft start unit and still have the same belt screech problem.....I'm really lost at this point..please help!!!!
Thread Starter
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Tuned
Joined: Jun 2015
Posts: 354
Likes: 8
From: Winchester, KY,USA
Sounds like the belt is slipping.Is your tensioner moving freely and putting a load on the belt?
Can you use belt dressing on the big serpentine belt? I know it quieted down my old V belts on another ride. It makes the belt a little stickier.
Logistics Pro
Joined: Mar 2005
Posts: 4,698
Likes: 47
From: Mexico, Missouri
Have you replaced the belt with a different brand?
Some brand belt's will squeal whereas others won't. I only use The Gatorback belt, which is now owned by Continental.
I've never had a problem except where I swapped everything dealing with belt squeal only for a Brand New Motorcraft belt to eliminate the problem on my '92, 300. It had me clueless, but ultimately the dealership said that the belt I had replaced with a New Gates belts, had stretched due to a worn out tensioner. Even though I replaced the tensioner with a Motorcraft, the new belt had already stretched and only a New belt solved all the squeal.
The service manager was a good friend with 25 years experience. I trusted his word.
About 2 years ago, I swapped the belt with a Gatorback, just to rule out a charging problem, and yet have an issue. The belt the dealership installed was 7 years old. I still have it.
Some brand belt's will squeal whereas others won't. I only use The Gatorback belt, which is now owned by Continental.
I've never had a problem except where I swapped everything dealing with belt squeal only for a Brand New Motorcraft belt to eliminate the problem on my '92, 300. It had me clueless, but ultimately the dealership said that the belt I had replaced with a New Gates belts, had stretched due to a worn out tensioner. Even though I replaced the tensioner with a Motorcraft, the new belt had already stretched and only a New belt solved all the squeal.
The service manager was a good friend with 25 years experience. I trusted his word.
About 2 years ago, I swapped the belt with a Gatorback, just to rule out a charging problem, and yet have an issue. The belt the dealership installed was 7 years old. I still have it.
Thread Starter
|
Tuned
Joined: Jun 2015
Posts: 354
Likes: 8
From: Winchester, KY,USA
Have you replaced the belt with a different brand?
Some brand belt's will squeal whereas others won't. I only use The Gatorback belt, which is now owned by Continental.
I've never had a problem except where I swapped everything dealing with belt squeal only for a Brand New Motorcraft belt to eliminate the problem on my '92, 300. It had me clueless, but ultimately the dealership said that the belt I had replaced with a New Gates belts, had stretched due to a worn out tensioner. Even though I replaced the tensioner with a Motorcraft, the new belt had already stretched and only a New belt solved all the squeal.
The service manager was a good friend with 25 years experience. I trusted his word.
About 2 years ago, I swapped the belt with a Gatorback, just to rule out a charging problem, and yet have an issue. The belt the dealership installed was 7 years old. I still have it.
Some brand belt's will squeal whereas others won't. I only use The Gatorback belt, which is now owned by Continental.
I've never had a problem except where I swapped everything dealing with belt squeal only for a Brand New Motorcraft belt to eliminate the problem on my '92, 300. It had me clueless, but ultimately the dealership said that the belt I had replaced with a New Gates belts, had stretched due to a worn out tensioner. Even though I replaced the tensioner with a Motorcraft, the new belt had already stretched and only a New belt solved all the squeal.
The service manager was a good friend with 25 years experience. I trusted his word.
About 2 years ago, I swapped the belt with a Gatorback, just to rule out a charging problem, and yet have an issue. The belt the dealership installed was 7 years old. I still have it.
Logistics Pro
Joined: Mar 2005
Posts: 4,698
Likes: 47
From: Mexico, Missouri
Here's another idea to ponder...
I've read where the diameter of the pulley on the alternator can cause belt squeal. I read it several times throughout the years on different vehicles, not just Ford related.
I don't remember what your original setup was, but you may want to check that your pulley size isn't what is causing your headaches. I remember that I had to swap the pulley size on my 300, of because I swapped in a 3G and the belted squealed. I luckily remember that was the only change, alternator pulley size was different, and once it swapped the original pulley onto the 3G, it quit squealing.
Just another idea.
I've read where the diameter of the pulley on the alternator can cause belt squeal. I read it several times throughout the years on different vehicles, not just Ford related.
I don't remember what your original setup was, but you may want to check that your pulley size isn't what is causing your headaches. I remember that I had to swap the pulley size on my 300, of because I swapped in a 3G and the belted squealed. I luckily remember that was the only change, alternator pulley size was different, and once it swapped the original pulley onto the 3G, it quit squealing.
Just another idea.
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Thread Starter
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Tuned
Joined: Jun 2015
Posts: 354
Likes: 8
From: Winchester, KY,USA
Here's another idea to ponder...
I've read where the diameter of the pulley on the alternator can cause belt squeal. I read it several times throughout the years on different vehicles, not just Ford related.
I don't remember what your original setup was, but you may want to check that your pulley size isn't what is causing your headaches. I remember that I had to swap the pulley size on my 300, of because I swapped in a 3G and the belted squealed. I luckily remember that was the only change, alternator pulley size was different, and once it swapped the original pulley onto the 3G, it quit squealing.
Just another idea.
I've read where the diameter of the pulley on the alternator can cause belt squeal. I read it several times throughout the years on different vehicles, not just Ford related.
I don't remember what your original setup was, but you may want to check that your pulley size isn't what is causing your headaches. I remember that I had to swap the pulley size on my 300, of because I swapped in a 3G and the belted squealed. I luckily remember that was the only change, alternator pulley size was different, and once it swapped the original pulley onto the 3G, it quit squealing.
Just another idea.
90 amp alternator for a '95 F150....
130 amp alternator for a '95 E350....
The pulleys have the same 6 groove design....although there is an available 8 grooved pulley for the heavier duty models....
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Logistics Pro
Joined: Mar 2005
Posts: 4,698
Likes: 47
From: Mexico, Missouri
The pulley design is the same, its pulley diameter that can affect length. Not all alternators have the same size diameter.
It's just something to cross off the belt squeal list.
Also, different pulleys can Run into different height to housing clearance. I have seen some that are shimmed further away from the alternator case housing on the shaft.
It's just something to cross off the belt squeal list.
Also, different pulleys can Run into different height to housing clearance. I have seen some that are shimmed further away from the alternator case housing on the shaft.
Thread Starter
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Tuned
Joined: Jun 2015
Posts: 354
Likes: 8
From: Winchester, KY,USA
The pulley design is the same, its pulley diameter that can affect length. Not all alternators have the same size diameter.
It's just something to cross off the belt squeal list.
Also, different pulleys can Run into different height to housing clearance. I have seen some that are shimmed further away from the alternator case housing on the shaft.
It's just something to cross off the belt squeal list.
Also, different pulleys can Run into different height to housing clearance. I have seen some that are shimmed further away from the alternator case housing on the shaft.
Logistics Pro
Joined: Mar 2005
Posts: 4,698
Likes: 47
From: Mexico, Missouri
Here's another idea..
Remove the fan from the water pump.
If the clutch for the fan is failing or has failed, it can create a higher load on the engine starting and that could also contribute to belt squeal.
If your absolutely certain that every accessory pulley and idler pulleys are straight and square, then I would try a shorter belt.
Remove the fan from the water pump.
If the clutch for the fan is failing or has failed, it can create a higher load on the engine starting and that could also contribute to belt squeal.
If your absolutely certain that every accessory pulley and idler pulleys are straight and square, then I would try a shorter belt.
Logistics Pro
Joined: Mar 2005
Posts: 4,698
Likes: 47
From: Mexico, Missouri
Quick question...
When you install the belt, how much does the tensioner rotate?
When I have mine installed I only have about 3/8th drop when it's loaded, so I have another 1/2" of stretch.
When you install the belt, how much does the tensioner rotate?
When I have mine installed I only have about 3/8th drop when it's loaded, so I have another 1/2" of stretch.
Thread Starter
|
Tuned
Joined: Jun 2015
Posts: 354
Likes: 8
From: Winchester, KY,USA
Here's another idea..
Remove the fan from the water pump.
If the clutch for the fan is failing or has failed, it can create a higher load on the engine starting and that could also contribute to belt squeal.
If your absolutely certain that every accessory pulley and idler pulleys are straight and square, then I would try a shorter belt.
Remove the fan from the water pump.
If the clutch for the fan is failing or has failed, it can create a higher load on the engine starting and that could also contribute to belt squeal.
If your absolutely certain that every accessory pulley and idler pulleys are straight and square, then I would try a shorter belt.
Quick question...
When you install the belt, how much does the tensioner rotate?
When I have mine installed I only have about 3/8th drop when it's loaded, so I have another 1/2" of stretch.
When you install the belt, how much does the tensioner rotate?
When I have mine installed I only have about 3/8th drop when it's loaded, so I have another 1/2" of stretch.
Logistics Pro
Joined: Mar 2005
Posts: 4,698
Likes: 47
From: Mexico, Missouri
You don't have to replace the clutch yet. Just remove the fan/clutch assembly from the water pump, reinstall the 4 bolts for the water pump pulley, and try running without the fan installed.
IF the belt were just on the edge of being to short, ie. tight that the tensioner is at the minimum, then it could cause problems.
IF the belt were just on the edge of being to short, ie. tight that the tensioner is at the minimum, then it could cause problems.
Thread Starter
|
Tuned
Joined: Jun 2015
Posts: 354
Likes: 8
From: Winchester, KY,USA
You don't have to replace the clutch yet. Just remove the fan/clutch assembly from the water pump, reinstall the 4 bolts for the water pump pulley, and try running without the fan installed.
IF the belt were just on the edge of being to short, ie. tight that the tensioner is at the minimum, then it could cause problems.
IF the belt were just on the edge of being to short, ie. tight that the tensioner is at the minimum, then it could cause problems.