Bearing noise from front of engine - how to diagnose? (1 Viewer)
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Do you happen to have these bearing numbers handy? Would be nice to have on hand. Can both of these be replaced?
aging fleet
SILVER Star
Another option if you don't feel like swapping the bearing, I ordered a new Toyota idler pulley off ebay a few days ago for only $34 shipped. In the description, the pulley is labeled with an older part number, but it checks out on Toyota's part site.
I should have it by the end of the week, if anyone is interested in how it looks, I can report back.
eBay link: GENUINE TOYOTA LEXUS DRIVE BELT TENSIONER IDLER PULLEY OEM 16604-50030 | eBay
I'm hoping to get some help on making sense of this squealing I have coming from my engine.
Over the last year I have replaced every single component that spins, including all timing belt parts. Mostly as preventative maintenance, nothing was broken.
Focusing on the fact that every single pulley and component are new, I am stumped on why my poor engine is squealing.
-It's heard when I first start it up, can be warm out ( 50degF) and it still does it. The noise typically goes away when up to operating temp.
- When 4 wheeling last week , she was working pretty hard mostly in 4 low hill climbing, and I could hear it crying out slightly. It wasn't ready to explode but it was enough to make me worry a bit
- Every part along the accessory and timing belt are new
- Replaced idlers twice because I was convinced they were defective
- On my third OEM belt because I am a moron
- Recently removed belt and cleaned it up to remove any possibly grease. Cleaned pulley
- When I remove serp belt the noise goes away.
- Stethoscope is not helping.
- When I say " I replaced " I mean "toyota service center replaced " but I am capable of diagnosing a bad pulley.
Question
- Are the bearings in the AC within the pulley/clutch or inside the compressor itself? I just replaced pulley / clutch with no difference
- Am I obsessing over something that I shouldn't care about? It's just frustrating to replace so many parts and still have squealing noises.
Over the last year I have replaced every single component that spins, including all timing belt parts. Mostly as preventative maintenance, nothing was broken.
Focusing on the fact that every single pulley and component are new, I am stumped on why my poor engine is squealing.
-It's heard when I first start it up, can be warm out ( 50degF) and it still does it. The noise typically goes away when up to operating temp.
- When 4 wheeling last week , she was working pretty hard mostly in 4 low hill climbing, and I could hear it crying out slightly. It wasn't ready to explode but it was enough to make me worry a bit
- Every part along the accessory and timing belt are new
- Replaced idlers twice because I was convinced they were defective
- On my third OEM belt because I am a moron
- Recently removed belt and cleaned it up to remove any possibly grease. Cleaned pulley
- When I remove serp belt the noise goes away.
- Stethoscope is not helping.
- When I say " I replaced " I mean "toyota service center replaced " but I am capable of diagnosing a bad pulley.
Question
- Are the bearings in the AC within the pulley/clutch or inside the compressor itself? I just replaced pulley / clutch with no difference
- Am I obsessing over something that I shouldn't care about? It's just frustrating to replace so many parts and still have squealing noises.
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I am thinking that the squeal is being caused by contamination on my belt or pulleys. Seeing as all pulleys are new OEM they shouldn't be producing these noises. In my experience it seems that squeaking and chirping are symptoms of bad pulleys whereas a squealing is a slipping or improperly tensioned / aligned belt.
I am going to clean up the belt and pulleys thoroughly and report back, I suspect the steering rack replacement maybe got some fluid on the belt.
I am going to clean up the belt and pulleys thoroughly and report back, I suspect the steering rack replacement maybe got some fluid on the belt.
Go to the auto parts store and get a spray can of belt dressing. With engine running (first started) spray a small amount on the belt. If the noise goes away immediately (perhaps to come back) then yes, you've found the source of your problem. IF it doesn't help then look to pulleys/bearings again.
Alternator.
It sounds 'bearing like' to me too and the alternator would be a good suspect.
Often times the bearings in them don't feel 'gritty' just spinning by hand, but when you increase the speed and add a 'load' (belt load and electrical) it will show up.
aging fleet
SILVER Star
If you’ve replaced the pulleys, belt and a/c components, maybe the power steering pump or alternator? There’s not much left riding on the accessory belt. I doubt it’s the belt if it persists after swapping it out 3x.
The alternator is brand new , so is power steering . Like , literally everything that spins under the hood is new OEM within the last 6 months.
I'm out of ideas , going to try to clean the belt and pulleys as I suspect maybe some power steering fluid got on it when swapping the rack last week. It's a new noise , the initial replacing of all these parts started because they were chirping and actually worn out, sounds crazy but this is a new noise , different than the previous issues that were resolved.
Will report back thanks for the advice
My belt/pulley squeal is driving me crazy on these cold mornings. I'm going to bring it back to Toyota since it's too cold to be messing around in my driveway. I mean it's not rocket science, all my pulleys and components spin smoothly so I'm at a loss.
- After looking closer at my repair records it looks like within the past 1-3 years ( 20-30k miles ) every single belt driven part has been changed EXCEPT the AC Compressor.
- Recent new serpentine belt didn't help
- All done with Toyota OEM by myself or with Toyota dealer
- It was my understanding the bearing for the AC is within the pulley / clutch assembly which has been replaced.
>> @flintknapper does the AC compressor have bearings inside that might squeal or is the clutch/pulley assembly the only possible suspect - Made this same noise last winter, went away all summer except when wheeling hard in 4 low, and back again this winter. So it can't be anything too devastating since nothing blew up yet
- Possibly defective tensioner but it feels good to me
- Belt and pulleys are clean
- When I take the belt off thankfully the noise goes away so we're not dealing with timing belt parts
- Goes away once up to operating temp, comes back if being worked hard off road but it's faint and most normal people wouldn't hear it.
Any ideas out there to help diagnose that I am missing?
Here is the noise
>>
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Sounds rather Cosmic-
Does it stop when you turn on/off AC compressor? When you pulled the belt off, and started the motor to listen- did you get any squeal then? Try swapping on a new belt and see if you get the squeal. I think when the acc belts have gotten wet in dusty dirty conditions that the cold start up squealing that dissipates after a few min is belt related. Mine does the same for a couple minutes ( not quite as loud and cosmic sounding as yours though) and all the pulleys except AC have been replaced.
Does it stop when you turn on/off AC compressor? When you pulled the belt off, and started the motor to listen- did you get any squeal then? Try swapping on a new belt and see if you get the squeal. I think when the acc belts have gotten wet in dusty dirty conditions that the cold start up squealing that dissipates after a few min is belt related. Mine does the same for a couple minutes ( not quite as loud and cosmic sounding as yours though) and all the pulleys except AC have been replaced.
Good advice , I think the audio recording gives it a bit if a different tone. I swapped belts with an aftermarket to help diagnose and not spend more on OEM but it didn't help. Maybe I should just throw another oem belt on there but I hate to just throw parts at it . Geez if it's as simple as a belt swap I'd feel like a dummy .
A squirt of some water on belt didn't change the noise
I haven't put a stethoscope on the actually AC compressor yet I'll give that a go next
Kind of just want whatever it is to blow up so I can fix it but going on a year and no change in symptoms
There are bushings in each end cap....but they wouldn't be making any noise unless the compressor were engaged in which case you could simply turn the compressor on and off and it would be apparent the compressor was the problem. The noise you are hearing sounds very much 'metal on metal' to me....but its origin is a mystery.
I would certainly want to have a second look at the alternator to be sure a bearing there (when under load) isn't the culprit or the rotor hitting the stator inside the case.
Thanks for the heads up . So it's fair to at replacing the AC compressor probably isn't worth the time or money . I Can't seem to get the AC to engage it's been single digit temps and even max cold I don't hear it click.
Toyota installed the clutch and pulley , is there a possibility the air gap in clutch could be a culprit ? I imagine the noise wouldn't go away if that was the case .
So the alternator was replaced with OEM a year ago , it failed within a few weeks and they replaced under warranty with another unit. Not sure if the noise existed back then or not.
I'll keep investigating and report back. Thanks for the assist
Some consideration:
Condition of ATF fluid in power steering and reservoir screen. Wrong fluid (power steering fluid is wrong) or bad old fluid and or clogged screen is very hard on vane pump
All to often idler pulley installed backward or not seated properly, or wrong cap washer used.
Tensioner pulley bearing.
Alternator tend to fail soon, if #1 under-shield missing.
If AC bearing. Switching AC on and off should make a big difference.
Bad drive belt are often worst hot (after warm up).
If sound present with drive belt off. Likely bad timing belt pulley bearing. Could also be water pump bearing, but should see coolant leak if that the case.
Free spinning pulley bearing are no good.
Condition of ATF fluid in power steering and reservoir screen. Wrong fluid (power steering fluid is wrong) or bad old fluid and or clogged screen is very hard on vane pump
All to often idler pulley installed backward or not seated properly, or wrong cap washer used.
Tensioner pulley bearing.
Alternator tend to fail soon, if #1 under-shield missing.
If AC bearing. Switching AC on and off should make a big difference.
Bad drive belt are often worst hot (after warm up).
If sound present with drive belt off. Likely bad timing belt pulley bearing. Could also be water pump bearing, but should see coolant leak if that the case.
Free spinning pulley bearing are no good.
Good advice, thanks.
All components mentioned are new OEM and check out, that is why I'm so puzzled.
- I can't seem to get the AC to click on recently when temps are this cold, even when set to max cold.
- Power steering pump is not that old, replaced with OEM, and flushed fluid at the time with Toyota ATF.
- Steering rack was also just replaced, flushed fluid at that time as well
- Turning the wheel doesn't change the noise
- With the serpentine belt off, the noise goes away which is a relief
I've got to get the belt off this weekend and dive into it a little deeper because the noise seems to be heard through several components when the belt is spinning.
PS - Reading back through this thread I really hope people aren't shoving socket extensions into the engine bay and trying to listen to noises. Stethoscope is less than 10 bucks.
Focusing on the idler pulley not being seated properly. I'll back it off and check on that this weekend but is it fair to say if that was the case, the noise would not go away once warmed up?
I was skeptical of the tensioner change over as well. The older style ( if I remember correctly ) had a larger pulley compared to the new style. I assume the tensioner accounts for this but it's strange that a smaller pulley on the tensioner would use the same length belt.
