Good to know others oem idler has
failed within a year. Hopefully the stethoscope honed in on the right part and the noise goes away for myself as well.
Bearing noise from front of engine - how to diagnose?
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Good to know others oem idler has
failed within a year. Hopefully the stethoscope honed in on the right part and the noise goes away for myself as well.
I'm looking at this like I need to run semi-annual bearing health checks or as part of spring/fall maintenance. Regular owners shouldn't need to worry about this.
Well I'm stumped .
Good news , with the accessory belt removed the noise goes away so I don't have to fret about a timing belt comcern
Bad news, replacing the idler did not fix the squeal / chirp. The stethoscope has deceived me
With the belt removed every pulley feels smooth with no free spin. Everything look clean as well.
Focusing on the fan , which has a new oem clutch. The engine is cold, it does free spin a bit which I think is normal. It does however have some noise happening.
Not sure how many more new OEM parts I need to examine , I can't imagine any of these parts are the cause but I am totally stumped .
Good news , with the accessory belt removed the noise goes away so I don't have to fret about a timing belt comcern
Bad news, replacing the idler did not fix the squeal / chirp. The stethoscope has deceived me
With the belt removed every pulley feels smooth with no free spin. Everything look clean as well.
Focusing on the fan , which has a new oem clutch. The engine is cold, it does free spin a bit which I think is normal. It does however have some noise happening.
Not sure how many more new OEM parts I need to examine , I can't imagine any of these parts are the cause but I am totally stumped .
Correct me if I'm wrong but when I spin the fan by hand , it would be the bearing in the fan bracket that it's turning . So if the noise goes away when my belt is removed , that bearing isnt turning either?
Let's see if this Google video link works an if anyone can hear that noise
New video by Mike
photos.app.goo.gl
Could the fan bracket be a suspect here?
Would It be foolish to try and stop the fan while it's being driven by the belt to see if noise stops?
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Sorry for so many postsCorrect me if I'm wrong but when I spin the fan by hand , it would be the bearing in the fan bracket that it's turning . So if the noise goes away when my belt is removed , that bearing isnt turning either?
Let's see if this Google video link works an if anyone can hear that noise
New video by Mike
Could the fan bracket be a suspect here?
Would It be foolish to try and stop the fan while it's being driven by the belt to see if noise stops?
I ran the motor for a few minutes while it was chirping away. After I shut it down and spun the fan it sounds a lot alot smoother .
Man this is a doozie . Even my wife put the ol stethoscope on and could hear it , in fact she said she doesn't even need the stethoscope its loud enough to hear from driver's seat.
I probed multiple areas with the stethoscope and I can hear it all over. Am I going crazy ? Probably
Correct. The fan pulley runs on the fan bracket bearing.
I see a slight bit of uneven movement when the pulley is turning. But that could be from the fan causing some resistance. My fan pulley was so bad that the fan would not freely spin like yours.Correct me if I'm wrong but when I spin the fan by hand , it would be the bearing in the fan bracket that it's turning . So if the noise goes away when my belt is removed , that bearing isnt turning either?
Let's see if this Google video link works an if anyone can hear that noise
New video by Mike
Could the fan bracket be a suspect here?
Would It be foolish to try and stop the fan while it's being driven by the belt to see if noise stops?
Is there any way to get the stethoscope into an area where you can touch the fan bracket and listen with the stethoscope?
Thanks for sharing , a stethoscope is more direct and accurate than a long extension.
It's usually not this difficult to find a bad pulley . I'm not sure what I'm missing
Yeah so I can probe around a bit in the area and it certainly sounds like it's coming from that region. But I also heard it clearly on the idler and that was a miss so I'm stumped.
I just can't imagine what could be going wrong. Everything is practically new and checks out when inspecting and spinning by hand.
With the engine cold and belt removed, I can hear some noise when spinning the fan by hand
With the engine still cold, belt installed , the noise goes away when spinning the fan by hand
Yes, when putting the probe on the bolt of the idler it is the same as before. I can poke around various places on the engine in that area and clearly hear it.
When poking around power steering / alternator side of motor , no noise.
The air from the fan overpowers the audio of this clip but the chirping can still be heard . Not seeing any wobble luckily
New video by Mike
photos.app.goo.gl
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Yes, when putting the probe on the bolt of the idler it is the same as before. I can poke around various places on the engine in that area and clearly hear it.
When poking around power steering / alternator side of motor , no noise.
The air from the fan overpowers the audio of this clip but the chirping can still be heard . Not seeing any wobble luckily
New video by Mike
Just a thought. IIRC the idler pulley bolts into the fan bracket. The noise might be transmitting to the idler bolt via the fan bracket?
Ah, very interesting. Thanks for sharing that. Looking at my service record Toyota replaced that January of last year at 200k miles, along with timing belt ,idler ,tensioner , water pump , etc...I'm now at 215k miles.
I even asked for the old parts and my old fan bracket was in the mix.
I just cant imagine how any of these parts have failed but currently the only thing making noise when spinning by hand is the fan, with the belt off.
The hardest part of changing the fan bracket involves the two long bolts that run through the front of the compressor.
Well if I could confidently diagnose the noise I could get Toyota to fix it since they were the ones who replaced it.
I guess the question at hand is..
>> How should the fan behave with a cold engine and the belt removed? Mine free spins several revolutions and certainly has a bearing noise going on.
Should It be silent or is a little noise normal ?
New video by Mike
photos.app.goo.gl
Well if I could confidently diagnose the noise I could get Toyota to fix it since they were the ones who replaced it.
I guess the question at hand is..
>> How should the fan behave with a cold engine and the belt removed? Mine free spins several revolutions and certainly has a bearing noise going on.
Should It be silent or is a little noise normal ?
New video by Mike
Another hint that may help is usually it takes about 10-15 second after the engine starts before the noise appears.
My fan bracket was so jacked up when I replaced it that I can't give a good description of how one that has been broken in would feel.
Roger that, I'll do some digging into the forums and see what I can learn.
If anyone out there happens to have their serpentine belt off this weekend, I'd be curious of how the fan behaves when cold and spun by hand. Any noise? Does it free spin a bit ?
With belt off, a good fan clutch typically has enough resistance, it doesn't spin. It's the fan bracket bearing that spins. It should be silent. You can also check fan bracket for lateral/side to side movement, with belt off. By grabbing pulley, belt would otherwise be riding on. Any movement is a bad fan bracket.