sounds like a bearing

[fishskuller]

Hello everyone, my problem is my 89 cherokee L6 4.0L has a noise coming from the grill area. This noise comes and go's and go's loud and could be quiet at times. Either way i know it's a problem, but the question is "How Big of a Problem?". I changed my alternator thinking the bearing was shot and and still makes the noise. The A/C compressor is fine, power steering is fine. I think this could be the water pump. What other bearings are in the front and what kind of trouble am i getting myself into? Right now i'm just waiting for something to break. any advice would be greatly appreciated.

 

[XJNick]

Hi,

The following contain bearings and are located in the front of the vehicle:

Alternator
P/S pump
Mechanical Clutch fan
Water Pump
Idler Pulley
A/C compressor
Electric radiator fan motor

-Nick :!:

 

[dingus]

could also be something simple like belt tension...

 

[fishskuller]

(1) 39.5 x 15 x 16.5 TSL for a spare

I just put a new water pump on and a brand new belt and it still makes a sound. I've noticed on the timing cover it looks like the belt was rubbing against it. I can't seem to get the belt to stop squealing. So i put the old belt back on and now that one squeals(it's so annoying). No one around here seems to have a belt tensioner so i've been trying to tighten it while the engine is running. Do you think this could be a pulley problem?

 

[graewulf]

to test belt tension, you should be able to twist the belt no more than 1/4 turn (no less either)

 

[fishskuller]

The serpinetine belt seems to be drifting off the fan clutch pulley and rubbing against the timing chain cover. What would cause the belt to be slowly drifting off the pulley? I think this is what sounds like a bearing making noise. How would you fix this problem? Please help me!!

 

[TwistedCU]

My yj was whining from a idler pulley. I almost changed the water pump before I finally figured out it was just an inexpensive pulley! It barely made any noise at all when I turned it by hand but when I replaced it everything was quiet again.

 

[graewulf]

sounds like a bearing going alright.. the fan attached to the water pump? if so, that would definitely do that.

 

[newbie]

Hey guys, i'm gonna start by directing you in the right direction! You absolutely DO NOT test belt tension by twisting it in any fashion, belt tension is correctly tested by a measurement of deflection over a given length, predetermined by the belt manufacturer. proper tension allows for the correct coefficient of friction between the belt and pulley surfaces, slippage causes glazing, glazing causes heat to build on the belt surface tempering the rubber and removing it's wear properties. The noise you describe "comes and goes" , therefore the cause must also change function or phase. Lets eliminate a few constant functions: water pump...constant load and usage, alternator....constant with the exception of charging(if you heard bearings in an alternator you wouldn't have a belt left), ac pump.....shut it off and see if the noise goes away! So we are left with a few simple items: do a hands on inspection on your fan clutch.......bad bearings will cause movement laterally, any movement at all.....change it,some lose oil and the internals cause noise at temperature, the on and off function of the clutch would explain the noise coming and going. I would expect you will find that the idler pulley is the cause of your grief.......as the load changes on the belt ie: charging, ac pump, power steering etc. the idler can resonate at different frequencies, when that freq. matches the engine freq. you get a noise that can resemble anything from a groan to a squeal. hope this helps you decifer your woes! yendor_kroc@hotmail.com

 

[TwistedCU]

Rustys exhaust system special

Welcome to the board Rodney (from email address). strange choice of usernames, what happens if you stick around a couple of years? I'tll be tough to call you newbie!

 

[fishskuller]

My Idler pulley was replace a year or two ago, so i think that's Ok. My fan clutch is not attached to my water pump. My fan clutch is attached to separate pulley under the Idler. The belt is not lining up on that pulley holding the fan clutch and it rubs against the timing chain cover. I can clearly see that the marks on the pulley from the belt are moving and the belt is sliding toward the timing chain cover, I think maybe i should replace that pulley. I thank everyone for all the help! I will let everyone know if this works.

 

[fishskuller]

I replaced the pulley and the serpentine belt still rubs against the engine. Though it only rubs when the engine gets warmer. The pulley lies between the crankshaft pulley and the alternator and holds the fan clutch. If anyone knows why this happens or has a similar problem please help me. Would the crankshaft bearings have anything to do with this? belt tension seems OK. and the belt is wearing down on the one side.