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jeepsrock
July 18th, 2005, 17:41
This morning i started my jeep and turned on the AC . As soon as i press the the gas pedal the front belt area sqeeks really bad. If i put it in park the noise is still present when i depress the pedal. I turned off the jeep and turned it on , turned on the AC and it was gone.

After a few hours i tried again and the same thing happened. I cheecked the belt and its in good condition.

what can i do.

pete

hicksrcool426
July 18th, 2005, 17:43
could be the A/C clutch

Lagooz00xj
July 18th, 2005, 18:39
put some tension into the serp. belt. There was a thread about this not too long ago on jeepforums. Mine did this in the beginning of the summer, i replaced the belt and tightened it until it stopped squealing.

pabloconrad
July 18th, 2005, 18:43
sounds like your belt is stretching a little and needs to be replaced (recommended) or tightened.

AZ Jeff
July 18th, 2005, 20:41
could be the A/C clutch
It's NOT the AC clutch. AC clutches don't squeal when they fail.

It's the serpentine accessory drive belt. It's either loose, or glazed.

The reason it squeals when the AC is on is becuase the AC compressor adds a SIGNIFICANT load to the belt when it's engaged.

jeepsrock
July 20th, 2005, 21:09
I honestly felt that the belt was tensioned enough initially but boy was i wrong.

Yesterday i ordered the famous krikit by napa (belt tension guage #kr2) and measured the tension and it was at 100 ft/lbs..lol

Anyway i looked it up in my chiltons book and it said it should be at 150-165 so i got it there and it seems all is well for now.

THanks
pete

Kevin3151
July 20th, 2005, 21:12
The last time I overtightened my belt the alternator bearings froze up on me. Now Im afraid to over tighten. Mine started squealing with the ac on recently too. The belt is less than a year old and probably just needs a tightening.
KH

dakotus
July 20th, 2005, 21:35
could you post the napa part number for that puppy. I just installed a belt last night, and would like to get the gauge to make sure its tight enough

jeepsrock
July 21st, 2005, 00:43
Just have the guy at napa enter kr2 in his computer and it shows up as "guage acc.", thats the one.

Damn kevin how far did you go with the belt for that to happen. I think mine is around 160-170 at the moment which i think is ok.

pete

schmiedel
August 1st, 2005, 16:04
I have read somewhere that the belt is well-tightened if you cannot turn it more than 90 on it's own axle. However, this is kind of a "subjective" method to test the tension. :D

jeepsrock
August 1st, 2005, 21:36
Just get a tention guage its only 14-16$, it works better.

pete

hicksrcool426
August 2nd, 2005, 10:00
my jeep squeels every once in a while, it will go months inbetween times. it only happens right after start up, and goes away after a little while, or if i rev it up a few times it will usualy stop squeeling. what would this be coming from?

AZ Jeff
August 2nd, 2005, 10:02
my jeep squeels every once in a while, it will go months inbetween times. it only happens right after start up, and goes away after a little while, or if i rev it up a few times it will usualy stop squeeling. what would this be coming from?
Probably belt, in combination with temperature/humidity conditions. Mine does it too, every once in a while. The dead give away that it's the belt is that it stops after a few seconds, once the belt warms slightly (due to slipping) and becomes more "grabby" on the pulleys.

pabloconrad
August 2nd, 2005, 10:19
my jeep squeels every once in a while, it will go months inbetween times. it only happens right after start up, and goes away after a little while, or if i rev it up a few times it will usualy stop squeeling. what would this be coming from?

It could be one of two things:

First it could be your alternator. When you start your engine, the battery has been drained a little and the alternator attempts to charge it. This puts an initial heavy load on the alternator creating drag between the pully and the belt. IF the belt is slightly loose, the pulley will spin slower (due to the load on the alternator) than the belt creating the high pitched squeal. If your battery is old or weak, then when you start your Jeep, the battery will drain more than a new one or one able to hold a good charge. This causes extra load on the alternator. As annual maintenance, you should have your battery and alternator checked to make sure the are in good condition.

Second, your AC may be on. When your engine is just started, the AC is trying to pump the freon from zero RPMs. This creates a tremendous amount of drag on the belt causing it to squeal. Make sure your AC is off before starting your car.

The reason the squeal goes away when you rev the engine a few times is it brings the AC or alternator pulley to speed with the belt, therefore no more drag, or squeal.

Hope this helps.

hicksrcool426
August 2nd, 2005, 11:08
thanks for the input. i was thinking it might be the alternator or the ac. batterie and alternator are in good shape though, checked them with a tester when i got the truck 8 months ago cuz my gauge is allways down a little, (espeicaly with all the lights, sound system, and ac on.) and a few weeks ago, and both times they read good on the tester. its happend with both the ac on and off when i start it. thanks for the reply

AZ Jeff
August 2nd, 2005, 16:12
The reason the squeal goes away when you rev the engine a few times is it brings the AC or alternator pulley to speed with the belt, therefore no more drag, or squeal.

That theory only works if the load due to that pulley (AC or alt.) is constant. Since the AC in particular is a CYCLING load, one would expect the squeal to return each time the compressor kicks on and, as you say, "brings the pulley up to speed".

Since that is not what's happening here, my theory of belt slip stopping after warm up makes more sense.

UNCC_99XJ
August 2nd, 2005, 20:14
I've also experienced some squeeling lately, but mines in a different situation.

Mine has been hapening when driving through moderate puddles while its pouring. The other day for work I was running a delievery in the pouring rain, a/c on low, turning around in our parking lot that always floods. Maybe about 4-5" of water. Wasn't flying through it or anything, talking speeds of 5mph or less. Turned the wheel to turn around and steering was very tight, tried turning it back and the belt (i presume the belt, cant exactly run out and listen up close in a downpour) started squeelin. let go of the wheel and it stopped. Steering returned to normal. Drove through a couple more puddles like that and had the same thing happen. Have done it in the past, with no squeelin at all and no problems. Any ideas? I checked the power steering fluid and its full, and the cap was on good and tight. I'm just guessing i got some water inbetween the belt and the pulley's and it slipped a bit. The odd thing is the engine still ran perfectly fine.

AZ Jeff
August 2nd, 2005, 20:37
I've also experienced some squeeling lately, but mines in a different situation.

Mine has been hapening when driving through moderate puddles while its pouring. The other day for work I was running a delievery in the pouring rain, a/c on low, turning around in our parking lot that always floods. Maybe about 4-5" of water. Wasn't flying through it or anything, talking speeds of 5mph or less. Turned the wheel to turn around and steering was very tight, tried turning it back and the belt (i presume the belt, cant exactly run out and listen up close in a downpour) started squeelin. let go of the wheel and it stopped. Steering returned to normal. Drove through a couple more puddles like that and had the same thing happen. Have done it in the past, with no squeelin at all and no problems. Any ideas? I checked the power steering fluid and its full, and the cap was on good and tight. I'm just guessing i got some water inbetween the belt and the pulley's and it slipped a bit. The odd thing is the engine still ran perfectly fine.
The engine does not need the accessory drive system to run at all, at least for short periods.

hicksrcool426
August 2nd, 2005, 23:23
The engine does not need the accessory drive system to run at all, at least for short periods.


to run for a moment, yes, but you DO need the acessory drive system to safely run the engine for more than a few minutes, cuz without a water pump your gonna over heat fairly quickly!!!

i used to run my 1944 MB with the generator not hooked up. (meaning only the water pump was driven) it ran fine off just the batterie for a few days, but i only ran it for short periods of time, and not vary often untill i finished the wireing.

AZ Jeff
August 3rd, 2005, 07:01
[QUOTE=hicksrcool426]to run for a moment, yes, but you DO need the acessory drive system to safely run the engine for more than a few minutes, cuz without a water pump your gonna over heat fairly quickly!!!
QUOTE]
Hence my use of the phrase "for short periods" in my response.

I have also run engines with no water in the cooling jacket. Again, this was for VERY short periods (60 seconds).

Don Becker
August 3rd, 2005, 10:54
Make that three of us with a recently-screeching belt . . . I too was suspecting the clutch. 'Been there before but 'have this tendency to always suspect the worst/most expensive . . . . unfortunately, 'often correct in that. I'll be checking the tension on mine this evening w/my krikit. Don

critik
August 3rd, 2005, 18:04
I have a similar problem. My Jeep is currently uninsured, and I haven't driven it or used it much since I got it, but I've noticed this.

When I tested the A/C at the dealer, it mad a screeching noise. I flipped it off and then on again, and the squeeling stopped. I drove it home, and then let it sit for a few days before I went out and started it (to move it). I turned the A/C on and there was no squealing. I waited about a week again to try it (to move it to replace a radiator), and the squealing started. I turned it off, and then on again, then the squealing stopped. Not sure what it could be.

LRRH
August 3rd, 2005, 18:34
i had the bearing in my AC compressor shit on me and basically start eating the clutch. bad squealing at first(only for a few seconds on startup). then it became a rumbling(after a few weeks) while the clutch was being eaten.

dakotus
August 7th, 2005, 14:39
how much $ to replace the clutch and bearings?

LRRH
August 8th, 2005, 09:34
i ended up just replacing the compressor with one from a junkyard. the shop tried to get the bearing(which Chryco doesn't sell) from a generic bearing place but they failed.

i have a massive leak from the evaporator (go figure) so I wasn't about to buy a new compressor when my AC system won't work anyway. stupid cheap parts.

dakotus
August 8th, 2005, 17:23
how much did that run ya?

Don Becker
August 12th, 2005, 23:27
Tightening the belt on my '88 took care of the squeal. But, it didn't on my wife's '91 . . . . this is a different story . . . that da*&^(*&ed belt has squealed since shortly after I first installed it. I'm pretty sure it's a Gates. When it first started squealing, I thought for sure it was the alternator . . . the shop thought so too, at first. Then they sprayed belt dressing on it and it stopped . . . I bought a can and used it as the squeal would return every day or two . . . . a mechanic told me that stuff is the worst thing I can use on a belt and he spread a dab of vasoline on the back of the belt and it went away for a week . . . . so, I keep dressing it with vasoline every time is starts squealing again (at least once a week). It is properly tightened and the belt is otherwise in perfect condition.

Now, I'm really tired of my wife telling me it's doing it again and I want to cure it!

Two questions: 1) 'any theories or experience with anything that would remove the glaze that must be built-up on the back of the belt and causing this? (a light sanding, acetone, ?, ?, ?) and, 2) are certain belt brands known for this problem?

Thanks! Don

Don