Squealing SERP belt!!! Out of ideas

[strokers]

Sounds like alternator is bad.

 

[bigdaddyof4]

I have done a lot of work on Rangers and F150s with these problems. What I do is very carefully take a broom stick or long screwdriver and listen to each bearing I can in the system. Put 1 end of the stick or the blade end of the screwdriver on the engine and your ear to the other end. Usually I hear a grinding noise or a louder squeal in 1 of them and replace that part to fix the problem. Sometimes old school methods work to save $$ but a bit scarey

 

[hankjr]

My $0.02. One of the mounting brackets might not be mounted flush to the front of the engine causing the centerline of that pulley to be out of line with the others. This means that there is some rubbing of the belt sideways to the rotational axis of the belt.

Hank

 

[chuzie]

Well seeing as i just missed my flight, i will have to wait a couple extra hours before getting back to troubleshoot this. Glad to have such a long list of ideas.

 

[chuzie]

Soaped the sides: no change
Top : no change
Bottom: jackpot.

Tensioner is tensioning and showing level 3 of 3 for acceptable tension/wear. Level 1 is considered least wear / most tension.
All pulleys rotate freely with no resistance or grinding.
Deflection test between alt and idler (appx 13") yielded about 1/2".
Compared current belt to new belt. Not sure if there should be such a difference here or if this is normal after break-in. New on left, current on right.

PS pulley has about .035" fore/aft play.

Pulleys look aligned although my peepers ain't what they used to be. Can some confirm?

Gonna clean pulleys and current belt next.

 

[strokers]

On my mustang setup I run my pulleys misaligned with out issue. My PS,ac are 1/8 in staggered while only couple thousand miles on them they haven't squealed. I was thinking that there is something wrong with the accessories that are placing to high load on belt causing it to slip thus squeal.

 

[chuzie]

Cleaned all pulleys with wire wheel and solvent. Cleaned belt with nylon brush and solvent. Still squeaks.

 

[Amac70]

i know i get a squeal every couple of years out of mine and just buy new belt, but the problem with mine is the tensioner. when you have it running give it a little gas and watch the tensioner, does it move at all. it should have some movement to it. If it doesn't i'd say that is your problem. its worn out and not moving properly.

 

[72Sport]

You might have a problem with belt contact on the alt or ac compressor. You may have to go to a larger pulley on one or the other. If the pulleys are not in exactly the stock position there won't be enough belt contact so the belt slips when you first start the engine or when the ac compressor clutch engages. I would guess the alternator pulley is too small in dia. If so find an alternator re-builder in the yellow pages and see if they will trade you for a larger one.

I fixed my belt slip on a Mustang serpentine system by increasing the dia of the alternator pulley (3g).

 

[01Dudley]

Didn't you just upgrade to a 3g alt? The belt is loose / tension doesn't have enough tension for the larger amp alt. Mostly does it when its cold because the battery is at its weakest and the alt is pulling more amps to charge it on top of it also be cold. The belt is slipping. Hold leverage on the tensioner and see if the squeaking stops.

 

[badmuttstang]

Like everyone else Im still going with tensioner as well

 

[chuzie]

... when you have it running give it a little gas and watch the tensioner, does it move at all....

It does move.

You might have a problem with belt contact on the alt or ac compressor. You may have to go to a larger pulley on one or the other. If the pulleys are not in exactly the stock position there won't be enough belt contact so the belt slips when you first start the engine or when the ac compressor clutch engages. I would guess the alternator pulley is too small in dia. If so find an alternator re-builder in the yellow pages and see if they will trade you for a larger one....

I would agree with that but it does it when warm and regardless of A/C use.

Didn't you just upgrade to a 3g alt? The belt is loose / tension doesn't have enough tension for the larger amp alt. Mostly does it when its cold because the battery is at its weakest and the alt is pulling more amps to charge it on top of it also be cold. The belt is slipping. Hold leverage on the tensioner and see if the squeaking stops.

Had 3g for a decade. Never had this issue before. This all started after I went from 302 to 351. ONLY thing different in this system is the billed balancer pulley. I thought it may be the issue and somehow prematurely wearing out my belt. I used a Gates belt wear tool and the balancer pulley has the same depth grooves as the stock Ford pulleys so I do not think it is an issue. Honding tension requires removal of fan and shroud. Not sure I am motivated enough to go that far.

Like everyone else Im still going with tensioner as well

What is the required ft-lb rating required for a tensioner? I can check it that way, right?

In the mean time, I threw my new belt on and no more squealing. I am sure this will happen again in 1000 miles.

 

[badmuttstang]

Not sure what the ft-lb rating is but you have an Explorer set up right rockauto lists it at under $30 local napa here has it for $28.

 

[Ourobos]

Did you change belt length when you went from 302 to 351w? 8.2" vs. 9.5" deck height, crank is further down about 1.3" so to speak. I originally said belt might be too long WAY back on page 1, now I'm leaning the other way with this new information.

 

[chuzie]

I did change belt length. How can it be too short if it fits?

 

[Ourobos]

It obviously doesn't fit right.. At least to me.. There's not enough tension on it.. Try one 1/2" shorter. ANY squeeking that's not an accessory bearing can be solved via the proper belt.. That's been my experience.

 

[Viperwolf1]

Shorter belt won't increase tension. The tensioner provides all the tension. The tensioner doesn't show tension with the indicator marks. It shows wear and stretch of the belt. Both are completely meaningless on a 351W with a longer belt. Change the tensioner and move on.

 

[chuzie]

Picked up a tensioner from NAPA for $53.00. Checked the torque for 90% full deflection on both the old and new tensioner.

Old Ford stock: 25-30 ft-lb
New aftermarket OEM: 20-25 ft-lb

I knew the outcome of this was going to be bad with those numbers.

Installed new tensioner with original belt and........

squeak, squeak, squeak.

Any other thoughts before I give up completely?

 

[Teal68]

Sorry if I missed it, but did you try the long screwdriver or wood handle listening trick yet to narrow down exactly where the noise is coming from?

 

[chuzie]

Sorry if I missed it, but did you try the long screwdriver or wood handle listening trick yet to narrow down exactly where the noise is coming from?

No worries. I have been wrong before too. ;D If we all had to be held to our advice here, this place would be a ghost town.

I tried a screwdriver, PCV pipe, and automotive stethoscope to the max extent possible without getting murdered by the fan. Nothing really stands out.

I may bite the bullet and remove the fan to dig deeper.