Fan Clutch ? Loud engine / fan noise

[flintknapper]

Does the bearing for the fan live within the fan bracket housing or the clutch?

I am chasing down some bearing noise. I just has Toyota replace both the clutch and bracket as part of the timing belt job. With the belt removed, I spin the fan and hear some bearing noise. It spins smoothly but I suspect the noise isn't normal and it could be the source of my squeaking.

Mike, with the belt removed....it might be difficult to determine which bearing (if either) was contributing to the noise. But unless a bearing were completely dry....it wouldn't make a squeaking noise anyway, particularly not recently replaced components.

But to answer your question: The fan clutch has a bearing (of sorts), so if you were to spin it by hand with the serpentine belt holding the fan bracket still....you should be able to isolate it from the bracket. IF you don't find the fan clutch to be the issue....then you'd pretty much have to remove the fan and fan clutch from the fan bracket to be able to turn it (unless the fan clutch offers enough resistance when cold to turn it).

The trouble with that...is sometimes when turning bearings 'by hand' you can't turn them fast enough to recreate the problem or without the belt tension....they just don't make a noise. You can however 'feel' a bad bearing or detect wobble (if any).

 

[Mike NXP]

Yes bearing is attached to fan bracket. Fan clutch, when going bad, will cause to engage completely when first starting up (hence roaring sound) as the fan is pushing more air than needed. There are plenty of tests out there to determine if fan clutch is going out (If I remember correctly, when at operating temp it should not be fully engaging so you should be able to stick some rolled up papers in the blades and have blades stop if operating properly, but don't quote me on that).

I had some bearing noise that I thought was coming from my idler pulley bearings. I replaced those and did not solve. When I had TB/WP done my guy said that bearing was "noisy" and felt a bit gritty causing the noise. I ended up replacing and noise is pretty much gone. This was at just over 200k. I had replaced my fan clutch right after I bought my truck in 2019 as it died on me one afternoon and caused the roaring sound. You can snake it out without having to remove upper rad hose but if you are replacing bracket already, it is kind of a "while you are in there" replacement.

OK so the bearing is within the fan bracket, shoot.

In my situation every part has been replaced, every pulley, belt, tensioner, etc. Fan clutch is new as well. I am stumped and can't keep throwing parts at it. Only thing I can determine is when spinning the fan, belt off, I hear some bearing noise. Since those parts are new it's kind of hard to justify replacing again.

 

[Mike NXP]

Mike, with the belt removed....it might be difficult to determine which bearing (if either) was contributing to the noise. But unless a bearing were completely dry....it wouldn't make a squeaking noise anyway, particularly not recently replaced components.

But to answer your question: The fan clutch has a bearing (of sorts), so if you were to spin it by hand with the serpentine belt holding the fan bracket still....you should be able to isolate it from the bracket. IF you don't find the fan clutch to be the issue....then you'd pretty much have to remove the fan and fan clutch from the fan bracket to be able to turn it (unless the fan clutch offers enough resistance when cold to turn it).

The trouble with that...is sometimes when turning bearings 'by hand' you can't turn them fast enough to recreate the problem or without the belt tension....they just don't make a noise. You can however 'feel' a bad bearing or detect wobble (if any).

Thanks for the advice, as you mentioned it's hard to condemn these parts to be bad with they are new OEM. However the install job done by Toyota is always up for debate but I have put many miles on it since the Tbelt job so I suspect everything is installed properly.

This is a doozie, I am usually good at diagnosing belt noises but everything feels as it should. Maybe I need to put a fresh belt on, but that would be the third time I have done that.

 

[flintknapper]

OK so the bearing is within the fan bracket, shoot.

In my situation every part has been replaced, every pulley, belt, tensioner, etc. Fan clutch is new as well. I am stumped and can't keep throwing parts at it. Only thing I can determine is when spinning the fan, belt off, I hear some bearing noise. Since those parts are new it's kind of hard to justify replacing again.

The fan clutch has an internal bearing and the fan bracket has a bearing. The fan clutch is attached to the fan bracket. So you have two possible culprits...but I wouldn't think either would/should be the source of your noise

 

[gregnash]

OK so the bearing is within the fan bracket, shoot.

In my situation every part has been replaced, every pulley, belt, tensioner, etc. Fan clutch is new as well. I am stumped and can't keep throwing parts at it. Only thing I can determine is when spinning the fan, belt off, I hear some bearing noise. Since those parts are new it's kind of hard to justify replacing again.

The part that has the four bolts on it that holds the fan clutch has a bearing that it spins on. This is likely where you are hearing the noise come from...

However, you are sure that you are hearing the noise come from this? Chow from ChowCares on YT did same thing chasing a bearing noise to find that it was his alternator. So may be worthwhile to test again.

 

[Mike NXP]

View attachment 2710074

The part that has the four bolts on it that holds the fan clutch has a bearing that it spins on. This is likely where you are hearing the noise come from...

However, you are sure that you are hearing the noise come from this? Chow from ChowCares on YT did same thing chasing a bearing noise to find that it was his alternator. So may be worthwhile to test again.

Thanks for the advice everyone, sorry to hijack the thread.

Alternator is brand new. Every single spinning part is brand new within the past 6 months. Parts were replaced as 200k maintenance so you could imagine why I am bummed I am still hearing a squeal. I've even replaced some parts twice ( idler and belt ) It does go away after a while but I heard it a week or so ago on the trails when the rig was working hard in 4low and made me realize I need to fix the problem.

I was skeptical of the smaller pulley that came with the new tensioner but it seems to be normal based on other threads. I suspected the smaller pulley could cause a tension / squealing problem but I'm sure the new tensioner is designed differently to work with the smaller pulley.

At this point it would be tough to justify replacing any other parts. When I remove the serp belt the noise goes away so I can narrow it down but still left with many suspects.

 

[kwon-offroad]

Question, do both OE and Aisin clutches have the blue spindle that bolts onto the pulley? Mine doesn’t. I don’t have fan issues so more about preventive maintenance since it is cheap and easy to replace.

 

[flintknapper]

At this point it would be tough to justify replacing any other parts. When I remove the serp belt the noise goes away so I can narrow it down but still left with many suspects.

Agreed, do not throw any parts at it. Removing the Serpentine Belt and the sound going away is a 'good' thing, since it means nothing to with the timing belt (and associated parts) is the source.

You could get a can of belt dressing and spray some on the belt with engine at idle when it starts the squeaking and see if it goes away. If it does...then its belt tension related.

 

[jahawk]

Thanks for the advice everyone, sorry to hijack the thread.

Alternator is brand new. Every single spinning part is brand new within the past 6 months. Parts were replaced as 200k maintenance so you could imagine why I am bummed I am still hearing a squeal. I've even replaced some parts twice ( idler and belt ) It does go away after a while but I heard it a week or so ago on the trails when the rig was working hard in 4low and made me realize I need to fix the problem.

I was skeptical of the smaller pulley that came with the new tensioner but it seems to be normal based on other threads. I suspected the smaller pulley could cause a tension / squealing problem but I'm sure the new tensioner is designed differently to work with the smaller pulley.

At this point it would be tough to justify replacing any other parts. When I remove the serp belt the noise goes away so I can narrow it down but still left with many suspects.

Try a Continental serpentine belt. I had a Vortech supercharger on a 5.0 and the only belt that wouldn't slip and squeak was Goodyear/Continental. They are the only belts I run now.

Jim

 

[Mike NXP]

Try a Continental serpentine belt. I had a Vortech supercharger on a 5.0 and the only belt that wouldn't slip and squeak was Goodyear/Continental. They are the only belts I run now.

Jim

I may have to try another belt(again )just for troubleshooting sake.

I pulled my belt this weekend and found all these tiny metal chips in it. I believe this is from the worn out tensioner because when I removed it , the mount was breaking apart and had similar material OR the worn out alternator.

Either way, after thoroughly cleaning I was hopefully I found the problem but no luck. Cleaned all pulleys as well, everything feels fine. So for now it's just annoying but I don't suspect anything will fail.

 

[gregnash]

Ok just realized something... there are a number of different LENGTH belts that fit the 2UZ based on application and accessories. So DOUBLE CHECK you are getting the correct length belt as the squealing may be simply that that belt is slipping ever so slightly because of the wrong length.

 

[Mike NXP]

Ok just realized something... there are a number of different LENGTH belts that fit the 2UZ based on application and accessories. So DOUBLE CHECK you are getting the correct length belt as the squealing may be simply that that belt is slipping ever so slightly because of the wrong length.

Interesting, I never thought to hard about that as I just went to Toyota parts guys and asked for the belt.

Looks like I have a 90916-02586

I don't really see any other options. Do we have a measurement / spec for belt tension / slack?

 

[gregnash]

Interesting, I never thought to hard about that as I just went to Toyota parts guys and asked for the belt.

Looks like I have a 90916-02586

I don't really see any other options. Do we have a measurement / spec for belt tension / slack?

Ok so yeah this is what I am talking about...

You can see all the different variants of belts... basically PK2245, pk2250, pk2255 are the main variants with the 45 being the shortest. They will all "technically" work but will be slightly longer or shorter (believe the 22xx is the measurement in MM of the belt). I would go to Partsouq and type in your VIN to cross reference part number for your particular year cruiser.

 

[Mike NXP]

Ok so yeah this is what I am talking about...
View attachment 2710260

You can see all the different variants of belts... basically PK2245, pk2250, pk2255 are the main variants with the 45 being the shortest. They will all "technically" work but will be slightly longer or shorter (believe the 22xx is the measurement in MM of the belt). I would go to Partsouq and type in your VIN to cross reference part number for your particular year cruiser.

Yeah good call, I just did the same search and noticed those results. I wonder if getting the smaller option would be an issue, I like to keep everything OEM and expect everything should work as expected. Hmmm, well this is a doozie. Maybe it's a simple as the belt being a bit to long based on the smaller diameter pulley on the tensioner but I suspect others would have run into this problem by now.

I'll keep plugging away and report back if I ever solve it.

 

[gregnash]

Yeah good call, I just did the same search and noticed those results. I wonder if getting the smaller option would be an issue, I like to keep everything OEM and expect everything should work as expected. Hmmm, well this is a doozie. Maybe it's a simple as the belt being a bit to long based on the smaller diameter pulley on the tensioner but I suspect others would have run into this problem by now.

I'll keep plugging away and report back if I ever solve it.

Worst case scenario you have a spare belt as a trail spare should something happen. Grab the smaller belt and give it a whirl and if it doesn't work out then chuck it in the back for that "just in case" situations.

 

[SDCORT]

I recall a couple years back my sons 2000 LC had one of the internal screws in the fan clutch come loose and it locked up the fan clutch, which made the fan sound like an airplane taking off when driving. Unfortunately the fan clutch was damaged beyond the point of easy repair when we took it apart. They are also full of a special viscocity silicon oil from what I remember, so not easily serviceable. We just put in a new AISIN fan clutch and all was good. Best of Luck

Do you remember the steps in which you took ? As I stare down, I cannot tell if I need to remove the fan shroud, the belts, upper radiator hose, etc etc. The shroud has 2 lines running across it , coolant reservoir attached to it, etc - and Id rather not remove it unless I have to. Cant seem to find a simple step by step breakdown of the process of getting the fan / clutch out .

 

[SDCORT]

Yes bearing is attached to fan bracket. Fan clutch, when going bad, will cause to engage completely when first starting up (hence roaring sound) as the fan is pushing more air than needed. There are plenty of tests out there to determine if fan clutch is going out (If I remember correctly, when at operating temp it should not be fully engaging so you should be able to stick some rolled up papers in the blades and have blades stop if operating properly, but don't quote me on that).

I had some bearing noise that I thought was coming from my idler pulley bearings. I replaced those and did not solve. When I had TB/WP done my guy said that bearing was "noisy" and felt a bit gritty causing the noise. I ended up replacing and noise is pretty much gone. This was at just over 200k. I had replaced my fan clutch right after I bought my truck in 2019 as it died on me one afternoon and caused the roaring sound. You can snake it out without having to remove upper rad hose but if you are replacing bracket already, it is kind of a "while you are in there" replacement.

How did you get it out without removing upper radiator hose ? Did you remove the fan shroud ? Im staring at this thing wondering how the heck am I going to get the clutch out.

 

[gregnash]

How did you get it out without removing upper radiator hose ? Did you remove the fan shroud ? Im staring at this thing wondering how the heck am I going to get the clutch out.

It comes out with a little elbow grease and creative thinking... Nothing else came off and you can rotate and push/pull it out the top.

 

[SDCORT]

Sounds like it could be your fan bracket bearing. Remove your belt and see how the bearing feels.

Jim

Jim, I released tension on the belt and the fan spins freely. With belt on, it is hard to turn by hand. What does this mean ?

 

[gregnash]

Jim, I released tension on the belt and the fan spins freely. With belt on, it is hard to turn by hand. What does this mean ?

With the belt off and spinning the fan you should be listening and feeling for any sort of grinding that you may feel/hear in the bearing in the bracket. With the belt on the fan clutch it self will move but not the bracket.