Hydraulic Fan Squeeling

[slidermike]

I have a 93 sc400.

I just replaced the radiator and since then, i get a high pitched squeel from the fan area.

I did a search here but have not found any good matches to my issue.

I checked the fluid level and they seem fine.

Should i drain the fan assembly fluids?

If so, how best to do that?

I read on another thread that the fan may have gotten "out of balance" but i don't know how to "Rebalance" it or what to do for it.

Any ideas would be great, as this is embarrasing to drive, not to mention that i could be letting something get damaged.

[UCF3]

What exactly is a high pitched squealing? Are you referring to a constant wizzing noise or are you listening to a wabbling noise?

If it's the wizzing noise, check your fan belts for cracks and general wear. You can spay a little water on it, to see if it does away.

[slidermike]

It sounds like a belt has started rubbing on something or a bearing is not working right.

It lessens in noise level when the engine revs.

It only started after i replaced the radiator (while i was adding the coolant).

I am not sure if its eminating from the fan area or the pully area.

I have made an apointment with lexus dealer to see what they can tell.

I don't want to run it until i have a costly fix.

[AWJ]

As you said in the title, the fan is hydraulic. There is no belt there, unless I'm missing something and it is like hydraulic clutch or something like that. Then it is a belt. Or the hydraulic fan drive is cavitating. Or the squeak is another accesory off that belt. Belt dressing might help. But if you've got a pully problem, you'll want to nip it. Check them all. Go from there, is what I would do.

[slidermike]

The lexus dealer looked @ it and said it was a loose radiator cap, allowing fluid to fling back onto the belt, thus the belt on the engine is squeeling.

I looked @ it and i don't see any fluid run off of in the cap area, nor do i see any signs of fluid on the belt.

I am going to get some belt dressing and see what that does for the squeel.

The more i listen and learn, the less i think its the fan assembly but rather the pullies or serpentine belt.

When i inspect the pullies, should any of them show any signes of give or what should i look for?

[K9crew]

It's easy enough to remove the serpentine belt and check your pulleys for play and noise. You can spin the alternator, idler pully, A/C etc but the idler pulley would be my first guess ... they go bad on new vehicles let alone older ones. My friend's Tundra had to go into the shop for a new idler pulley during the first six months. Anyway, the pulleys should rotate freely and quietly with no play or lateral runout.

:)

[slidermike]

OK i will look into it this weekend.

[slidermike]

Problem solved.

I found that the over flow tube that attaches under the radiator cap was dripping excess coolant into the path of the air from the fan, so it would put just enough moister on that corner of the belt / pulley area to cause a squeel when the engine was up to running temp.

I fixed that by puting a hose extension on the end and now the excess will go to the ground.

I believe i may have just slightly over filled the radiator resevoir and now its expelling the overflow a few drops @ a time.

Thanks for the help guys.