Been hearing a loud squeal for a while now, heard this sometimes when it rained figured the belt was just wet, not it occurs every start. Replaced belt and tensioner pulley a couple years ago, just did power steering pump but kept the original pulley wheel. Just did idler pulley. Removed belt completely and heard no squeal. I kind of just want to know what exact pulley wheel it is, and try and replace the part. I cannot locate the noise hence it’s so loud and it doesn’t sound like it’s coming from any specific location. Wonder if anyone has had or has a similar problem, thanks for reading!
NEED HELP Belt Squeal Diagnosis
- Thread starter benjaminblazer
- Start date
A few other Sealed Bearing Weak Points that if failing, can invite the Outer Contact Surfaces to *Chirp & Squeak* from the resulting constant rotational misalignment between the Belt inner "Teeth" and - or their Outer Smooth Surfaces:
(1) The Water Pump - If the Fan Shroud WOBBLES Excessively... then the WP Bearing(s) are suspect. The sheer Mass of the Wobbling Plastic Circular Shroud is enough to overcome the tightness of the Serpentine Belt with the "Bell Like" Outer Race of the WP Pulley and become VERY Noisy.
(2) The Idler Pulley - Worn Bearings and Minor WOBBLES can cause the Belt-to-Metal contact to shift suddenly and make noises.
(3) The Belt Tensioner Pulley - Same as (2)...
(4) The Alternator Bearings - Rare ..and would produce a more consistent *Bearing Chirp or Growl* if present under increased RPM.
These problems are very hard to identify by merely spinning the outer Bearing Races when the Serpentine Belt is removed. However, if you are able to Tilt the Upper Center Tan Plastic Fan Shroud Fore and Aft to any degree.... then the Water Pump Bearing(s) will be on their way OUT and the WP should be replaced.
(See @Matt 's Epic WP R&R Thread for the Best Procedures to Follow).
(1) The Water Pump - If the Fan Shroud WOBBLES Excessively... then the WP Bearing(s) are suspect. The sheer Mass of the Wobbling Plastic Circular Shroud is enough to overcome the tightness of the Serpentine Belt with the "Bell Like" Outer Race of the WP Pulley and become VERY Noisy.
(2) The Idler Pulley - Worn Bearings and Minor WOBBLES can cause the Belt-to-Metal contact to shift suddenly and make noises.
(3) The Belt Tensioner Pulley - Same as (2)...
(4) The Alternator Bearings - Rare ..and would produce a more consistent *Bearing Chirp or Growl* if present under increased RPM.
These problems are very hard to identify by merely spinning the outer Bearing Races when the Serpentine Belt is removed. However, if you are able to Tilt the Upper Center Tan Plastic Fan Shroud Fore and Aft to any degree.... then the Water Pump Bearing(s) will be on their way OUT and the WP should be replaced.
(See @Matt 's Epic WP R&R Thread for the Best Procedures to Follow).
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Mooseman
Moderator
Also check pulley alignment.
If yours an EXT? I have found that on those the wrong belt is listed and have to go to the next shorter one for proper tension. When I installed an EXT rack and pinion along with its smaller pump pulley, the belt I got was too long and the tensioner didn't put enough tension on it. Check this post:
If yours an EXT? I have found that on those the wrong belt is listed and have to go to the next shorter one for proper tension. When I installed an EXT rack and pinion along with its smaller pump pulley, the belt I got was too long and the tensioner didn't put enough tension on it. Check this post:
Don’t have an ext but very helpful, thanks!
My suspect is the ac pump or the water pump, that’s all that’s left to replace, going to check on tan fan today! Alternator has been replaced with a autotech 270amp and i don’t believe it is that.
Quick question, when i replaced the power steering pump, i reused the old pulley, used a puller and put it on the new one. Do you think the pulley could be the issue? I figured no because it’s stationary on the pump, all of the spinning is going on inside of the pump.
Mooseman
Moderator
Gotcha, just ordered another tension pulley to replace it just in case.As long as it's installed flush to the shaft, it should be properly aligned.
Check the tensioner. There should be an arrow or triangle that should be pointing to an area with the belt on and engine off. Similar to this one:
It should be within this area for proper tension.
@mrrsm @Mooseman thanks for the help so far really appreciate it, so put the new tensioner pulley on, no change, didn’t think it was the case but figured i’d eliminate it. Here is a link to the google drive: https://drive.google.com/file/d/1-9WrGoLfyWsPc7MXEMvj5uN11YPPfsFy
This shows the present noise occurring, and also the fan shroud you mentioned above. Doesn’t seem to be crazy loose, only somewhat loose because of the broken front clip.
Also i’m guessing this is the “shroud” you’re referring to correct? (picture linked)
This shows the present noise occurring, and also the fan shroud you mentioned above. Doesn’t seem to be crazy loose, only somewhat loose because of the broken front clip.
Also i’m guessing this is the “shroud” you’re referring to correct? (picture linked)
Attachments
No... Please forgive my imprecision in the choice of nomenclature...
(1) The "Shroud" I meant to describe is the Outer Ring of the Rotating Tan Plastic Air Guide or Air Dam that is designed to form a partial vacuum inside of that Black Plastic Shroud, helping to ensure that Cooler Air is being guided inside of that Black Shroud shown in your image and then pulled on through the body of the Radiator Aluminum Cooling Fins to draw off the Heat in the Water Column created by the Engine and Transmission:
(2) When the Internal Bearings inside the Water Pump begin to Fail... it allows that Tan Rotating Plastic Mass to *Wobble" even more excessively about its Outer Orbiting Edge, giving the strongest clue that the Ball Bearings are -=NOT=- running true inside of the Water Pump Roller Ball Bearing -to- Bearing Race(s) contact surfaces hidden within:
(3) When this happens... the Smooth, Outer surface of the Bell-Shaped Pulley placed over the Large, Threaded Water Pump Shaft also suffers, since the Tan Fan Screw On portion is held firmly to the Water Pump at its Center, while the Four Gray Galvanized Bolts hold that Bell Pulley solidly onto the Water Pump's Outer Flange.
(4) THIS is the Point Of Failure Failure due to this excessive freedom of movement loose bearings will allow and thus, the OUTSIDE Smooth Surface of the Serpentine Belt can perform the accidental "Slip-N-Slide", causing that irritating "Chirping Sound" to occur, amplified by the Bell-Shaped Cavity inside of the WP Pulley.
(5) When the Tan Plastic Shroud is cast and formed at the Factory, the GM Engineers try to overcome this tendency for the *Wobble* to invite Bearing Failure by placing Balancing Clip-On Weights upon the Leading Edges of some of its Fan Blades at certain points (Inside the Red Circle) while spinning it up to Speed on a Test Stand in order to eliminate that *Wobble*. However, if any of those minuscule "Wheel Weights" are either Moved or Lost, this "Out Of Balance" condition will invite an Early Failure of the Water Pump Bearings to occur:
(6) Ordinarily, the New ACDelco Internal Water Pump Bearings will prevent this issue by having smooth running tolerances. And so at first, this minimizes the*Wobble* of that Tan, Rotating Circular Air Dam. However, any imbalance of this arrangement will eventually cause things to get worse over time and invite such failures.
(7) It is important to remember that The Grooved AND The Smooth Surfaces on opposite sides of the Serpentine Belt are BOTH working to transfer an ENORMOUS amount of energy from the Grooved Harmonic Balancer-Crankshaft Pulley and they WILL try to escape their guidance over the entire system of Power Hungry Accessories they are meant to Drive.
(1) The "Shroud" I meant to describe is the Outer Ring of the Rotating Tan Plastic Air Guide or Air Dam that is designed to form a partial vacuum inside of that Black Plastic Shroud, helping to ensure that Cooler Air is being guided inside of that Black Shroud shown in your image and then pulled on through the body of the Radiator Aluminum Cooling Fins to draw off the Heat in the Water Column created by the Engine and Transmission:
(2) When the Internal Bearings inside the Water Pump begin to Fail... it allows that Tan Rotating Plastic Mass to *Wobble" even more excessively about its Outer Orbiting Edge, giving the strongest clue that the Ball Bearings are -=NOT=- running true inside of the Water Pump Roller Ball Bearing -to- Bearing Race(s) contact surfaces hidden within:
(3) When this happens... the Smooth, Outer surface of the Bell-Shaped Pulley placed over the Large, Threaded Water Pump Shaft also suffers, since the Tan Fan Screw On portion is held firmly to the Water Pump at its Center, while the Four Gray Galvanized Bolts hold that Bell Pulley solidly onto the Water Pump's Outer Flange.
(4) THIS is the Point Of Failure Failure due to this excessive freedom of movement loose bearings will allow and thus, the OUTSIDE Smooth Surface of the Serpentine Belt can perform the accidental "Slip-N-Slide", causing that irritating "Chirping Sound" to occur, amplified by the Bell-Shaped Cavity inside of the WP Pulley.
(5) When the Tan Plastic Shroud is cast and formed at the Factory, the GM Engineers try to overcome this tendency for the *Wobble* to invite Bearing Failure by placing Balancing Clip-On Weights upon the Leading Edges of some of its Fan Blades at certain points (Inside the Red Circle) while spinning it up to Speed on a Test Stand in order to eliminate that *Wobble*. However, if any of those minuscule "Wheel Weights" are either Moved or Lost, this "Out Of Balance" condition will invite an Early Failure of the Water Pump Bearings to occur:
(6) Ordinarily, the New ACDelco Internal Water Pump Bearings will prevent this issue by having smooth running tolerances. And so at first, this minimizes the*Wobble* of that Tan, Rotating Circular Air Dam. However, any imbalance of this arrangement will eventually cause things to get worse over time and invite such failures.
(7) It is important to remember that The Grooved AND The Smooth Surfaces on opposite sides of the Serpentine Belt are BOTH working to transfer an ENORMOUS amount of energy from the Grooved Harmonic Balancer-Crankshaft Pulley and they WILL try to escape their guidance over the entire system of Power Hungry Accessories they are meant to Drive.
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Gotcha makes more sense now, but as you seen in my video, there wasn’t really any wobble to it like the video you shown, as well as the noise was a different pitch. I was trying to move the whole pump as well and not really budging up and down nor left to right. Is it possible for the crank to make this noise?
Not likely... No. The only issues that would allow the Grooved Harmonic Balancer to *Hunt* Fore & Aft would be a catastrophic failure either of the Crankshaft TTY Bolt holding the Harmonic Balancer in place using 110 Foot Pounds of Torque (+ 180 Degrees of Additional Torque Angle) of strong clamping force being applied to the Nose of the Crankshaft...
-= Or =-
... if the Thrust Bearings found at the #5 Mains - to - Crank Journal Location that more or less restrict any Crankshaft movements longitudinally to a very small fraction ...had failed:
The Torque imparted perpendicular to the Rotating Mass due to the Conservation of Angular Momentum during Counter-Clockwise Crankshaft Rotation ...makes these Thrust Bearings an Absolute Necessity and Life Ending for Engines whenever they FAIL... (See Attached PDF)
You would also be seeing a possible combination of P0014 and P0017 Codes... or even a P1345 Code if this were the case. Besides that... all of the Power driving the Accessory Section would show that Serpentine Belt bouncing around so dramatically that a problem with the Crankshaft would clearly be evident:
Excerpt from the related TSB:
"If all these screens are present (in the CPAS), measure the crankshaft end play to determine if it is within the specification of 0.0044" - 0.0153" (0.112 - 0.388 mm). Typically, if excessive crankshaft end play is causing this concern, it will be obviously out of specification by .050" or more. If crankshaft end play is within specification, replace the camshaft actuator solenoid.
If the crankshaft end play is obviously out of specification, inspect the engine block for damage due to contact with the crankshaft.
If there is no engine block damage present, disassemble the engine and inspect the following components for damage due to thrust bearing debris in the engine oil: all bearings, all journals, all valve-train components, all timing components, and the crankshaft..."
That excessively Long GM 4.2L LL8 Engine Crankshaft is held fast by Seven (7) Main Bearing Caps (focusing on that #5 Thrust Bearing Position) aided by a rigid Steel Cradle running its entire length and they would resist any such dramatic motions affecting the changes in force vectors governing the Accessory Section Serpentine Belt Driving Mechanism.
phys.libretexts.org
-= Or =-
... if the Thrust Bearings found at the #5 Mains - to - Crank Journal Location that more or less restrict any Crankshaft movements longitudinally to a very small fraction ...had failed:
The Torque imparted perpendicular to the Rotating Mass due to the Conservation of Angular Momentum during Counter-Clockwise Crankshaft Rotation ...makes these Thrust Bearings an Absolute Necessity and Life Ending for Engines whenever they FAIL... (See Attached PDF)
You would also be seeing a possible combination of P0014 and P0017 Codes... or even a P1345 Code if this were the case. Besides that... all of the Power driving the Accessory Section would show that Serpentine Belt bouncing around so dramatically that a problem with the Crankshaft would clearly be evident:
Excerpt from the related TSB:
"If all these screens are present (in the CPAS), measure the crankshaft end play to determine if it is within the specification of 0.0044" - 0.0153" (0.112 - 0.388 mm). Typically, if excessive crankshaft end play is causing this concern, it will be obviously out of specification by .050" or more. If crankshaft end play is within specification, replace the camshaft actuator solenoid.
If the crankshaft end play is obviously out of specification, inspect the engine block for damage due to contact with the crankshaft.
If there is no engine block damage present, disassemble the engine and inspect the following components for damage due to thrust bearing debris in the engine oil: all bearings, all journals, all valve-train components, all timing components, and the crankshaft..."
That excessively Long GM 4.2L LL8 Engine Crankshaft is held fast by Seven (7) Main Bearing Caps (focusing on that #5 Thrust Bearing Position) aided by a rigid Steel Cradle running its entire length and they would resist any such dramatic motions affecting the changes in force vectors governing the Accessory Section Serpentine Belt Driving Mechanism.
11.2: Torque and Angular Momentum
phys.libretexts.org
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Alright with this said, do you know what would be a good way to test the ac pump for failure? Not getting any codes, absolutely no wiggle, wondering if it’s gotta be the ac, makes some noise when i spin it but not alot. Weird thing is the cricket like noise when the engine is on, sounds like its from the middle of the belt location.Not likely... No. The only issues that would allow the Grooved Harmonic Balancer to *Hunt* Fore & Aft would be a catastrophic failure either of the Crankshaft TTY Bolt holding the Harmonic Balancer in place using 110 Foot Pounds of Torque (+ 180 Degrees of Additional Torque Angle) of strong clamping force being applied to the Nose of the Crankshaft...
-= Or =-
... if the Thrust Bearings found at the #5 Mains - to - Crank Journal Location that more or less restrict any Crankshaft movements longitudinally to a very small fraction ...had failed:
View attachment 115413View attachment 115414
The Torque imparted perpendicular to the Rotating Mass due to the Conservation of Angular Momentum during Counter-Clockwise Crankshaft Rotation ...makes these Thrust Bearings an Absolute Necessity and Life Ending for Engines whenever they FAIL... (See Attached PDF)
View attachment 115415
You would also be seeing a possible combination of P0014 and P0017 Codes... or even a P1345 Code if this were the case. Besides that... all of the Power driving the Accessory Section would show that Serpentine Belt bouncing around so dramatically that a problem with the Crankshaft would clearly be evident:
Excerpt from the related TSB:
"If all these screens are present (in the CPAS), measure the crankshaft end play to determine if it is within the specification of 0.0044" - 0.0153" (0.112 - 0.388 mm). Typically, if excessive crankshaft end play is causing this concern, it will be obviously out of specification by .050" or more. If crankshaft end play is within specification, replace the camshaft actuator solenoid.
If the crankshaft end play is obviously out of specification, inspect the engine block for damage due to contact with the crankshaft.
If there is no engine block damage present, disassemble the engine and inspect the following components for damage due to thrust bearing debris in the engine oil: all bearings, all journals, all valve-train components, all timing components, and the crankshaft..."
That excessively Long GM 4.2L LL8 Engine Crankshaft is held fast by Seven (7) Main Bearing Caps (focusing on that #5 Thrust Bearing Position) aided by a rigid Steel Cradle running its entire length and they would resist any such dramatic motions affecting the changes in force vectors governing the Accessory Section Serpentine Belt Driving Mechanism.
11.2: Torque and Angular Momentum
It is true that the Electro-Magnetic A/C Compressor Clutch can develop "Dry Bearings" that can get Rusty... and Noisy. With the Serpentine Belt Removed... You might try spinning and statically tilting the "Free-Wheeling" portion with the Serpentine Pulley aspect by hand feeling for looseness and listening for either Squeaking Noises of Bearing Growl and if present, it would indicate a possible source... especially if you turned the A/C ON and the noise disappeared after the Two Steel Halves lock up and the Compressor begins to run.
If this accessory spot turns out to be the culprit... GMT Nation has a few Threads describing the R&R... but it requires the Flexibility of a Circus Contortionist ... some Patience... and some Specialty Tools and Talent to perform the A/C Clutch Only R&R:
gmtnation.com
If this accessory spot turns out to be the culprit... GMT Nation has a few Threads describing the R&R... but it requires the Flexibility of a Circus Contortionist ... some Patience... and some Specialty Tools and Talent to perform the A/C Clutch Only R&R:
Replace compressor clutch or whole compressor?
I took my 02 TB to the mechanic for a grinding noise coming from the compressor, mechanic said it was the AC clutch assembly. My question is is it worth it to only replace the assembly? The mechanic said that if the assembly is bad there is a 90% chance the compressor is bad to but the AC worked...
gmtnation.com
Mooseman
Moderator
You can find out if it's an accessory or the belt itself making the noise. While it's running and making the noise, spray some water from a spray bottle or toy water gun on the belt. If the noise stops, it's the belt. If not, it's an accessory or idler pulley.
If it is the belt, check pulley alignment and the water pump bearing.
When you re-installed the PS pump pulley, is it flush with the shaft like this?
If it is the belt, check pulley alignment and the water pump bearing.
When you re-installed the PS pump pulley, is it flush with the shaft like this?
