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Replaced serp belt 2 day A/C squeal?

matuva said:
any part # for that green stuff ? Do you get it for the 1996 and + ?
Click to expand...
If you go on NAPA's web site and put in your truck it will give 2 choices for the belt.Reg and HD. As far as I know napa and gates numbers aren't the same like napa and wix.
 
Fold a piece of 180/220 sand paper in half and with the engine running carefully put it between the air gap in the clutch and compressor for a min. or 2, then take it out and turn the ac on and see if it squeals. This is for diagnostic purpose to confirm it's the clutch slipping.
 
Is your tensioner near max travel with the squealling belts?

I had issues with belt stretch then squeal. I tried a few new belts and the tensioner moved to near full stroke over a few days to weeks then the belt would squeal occasionally accelerating. A Carquest Gold belt fixed the squeal for me and it seamed to have the best feel for grip on the backside and was the thickest belt of several I compared. The funny thing then was the tensioner still moved albiet a good bit slower to full stroke even with the "best" carquest belt but then stayed and it has never squealled now 80K + miles later still quiet.

My tensioner always felt good and is OE. I did replace the pulley wheel on the tensioner but it did not make any difference.
 
The problem with a worn tensioner is over tension. As it slowly self distructes inside it will bind and not release causing belt stretch and excessive bearing wear in all the belt driven accessories. As a rule ,when the bearing in the pulley starts to get loose the insides are shot also. For less than the price of a belt ,it's not worth taking the chance of wrecking all the other accessories ,in my opinion.
 
Thanks for sharing. The tensioner is pretty new that & the belt were both replaced last Oct. right before I purchased the truck by the PO.

The tensioner is operating in the center of the travel, belt tension seems correct, but I am going to pull the new belt & check the tensioner bearing tonight after I get home from work.

Road the bike to work today, gave the 6.5 the day off :thumbsup:

Thanks again everyone, I'll get back to ya's :grouphug:
 
Ok just checked the tensioner it's smooth as glass. The pully on the AC not so much. Spinning the AC pulley sounds like it's dragging on the edges...metal to metal? Clutch front bearing new compressor...what say you?
 
Where did you get the tensioner? I say this because our good buddies in China and other cheap auto parts stores tend to stock the wrong one for the older passenger side compressor engines. Rather you get the later model years lower spring tension driver side compressor tensioner.

Was the pulley on it thinner than the OEM one and belt riding toward the back almost off the pulley?

The spring in the older units are stronger because they have to put up with the compressor start up load without slacking and squealing the belt. The driver side compressor mounting does not have this issue and R134a's higher pressures mean the weaker tensioner will be forced to move on compressor start up. Movement means belt slack and squeal.

I had to buy a new tensioner from the GM dealer. The Autozone one I got would do the same hot start squeal and take 2-3 tries to even get the compressor spinning. Course it is hotter here... But the part Autozone gave me had a weaker spring - for the newer pickups with driver side compressors.

The metal to metal sound may also be a mis-adjusted compressor clutch dragging.
 
Not sure the previous owner installed the tensioner. The belt is running in the center of the wheel & the tensioner position seems to be about 50% of the travel...belt tension seems correct to me.

How do I adjust the AC clutch?
 
Check the alternator bearings also, over the years 2 primary sources of squeal I've found, belts, some have stretched within 1 day and are loose/slipping, (crappy rubber) GY Gatorback among the worst of the bunch, and alternator bearings make it sound like a bad tensioner bearing, or ac clutch
 
How do I adjust the AC clutch? with a feeler guage. You have to have the right air gap between the comp. and clutch. Although you said that they are making contact when spinning by hand with the belt off. If this is the case it is warped from slipping and heating up.You need to just unplug the compressor. then start the truck w/ac on and then watch the clutch engage while you plug comp. wire in. it should lock right up when the magnet is energized. It should click and lock instantly.If you see it slip and hear it squeal problem solved ,buy a new clutch. If it locks and still squeals check alt. and outer balancer rubber for seperation, and vac pump if still equipped. That's all that's left???? Maybe a bad flu-flu valve. could be sticking from lack of spontaneuos lubrication.
 
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As to the clutch test above robzombie4551 mentioned. Check your grounds too! A weak clutch magnet can cause the burn up. A bad ground can make a good magnet weak.

You should also watch the belt tensioner for movement when the ac compressor kicks in. I'll check my 93 and see how much it moves on a successful compressor start-up, if any.

Reference: New clutch $86.00. Rebuilt compressor - $110.00 plus system evac and recharge, oil, accumulator and o-tube. And the first thing that went on my rebuilt compressor was the clutch. 1 week 1000 miles and broke 1 of the 3 'springs'...
 
Pulled the belt spun the alternator it seems fine, the tensioner seems fine, the belt & tension of the belt appear to be OK.

Pulled the AC compressor bolts so I could lay it on it's side and sprayed the clutch assembly down with some brake cleaner & then chased that out with silicon lube about five times. Reinstalled the AC compressor & ran the motor with the ac off at 1st & then for about 15 minutes more...lubing the clutch assembly while kicking the AC on & off about 50 times or more. No squeal...we'll see how long it last...?

Oriley's parts has the clutch assembly a Murray - Reman Gm Frigidaire/Harrison R4 Radial Clutch assembly Part Number: 48656 for $92.99 in stock along with the puller that you can use free with a deposit return.

Back to my regular concern about replacement parts that can't make it past my next oil change interval :confused:
 
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