Quick a/c belt question.

[Italianstln323]

The other day, my ac compressor belt snapped on my 2002 Tahoe 5.3L. So I ran to Kragen and bought a new goodyear gatorback ac belt, and a serpentine as well, (I figured i might as well replace it too while i'm down there as it has 94000 miles.)

So I switched them out no problem, and the serpentine runs beautifully, but when i turn on the ac, and it engages, i hear a loud-ish fast clicking noise that is heard when I accelerate. It goes away when i'm at speed. Does this sound like a problem with the ac tensioner pulley, or maybe something else?

[ct9a]

If the sound wasn't there before, than I would definitely check into whatever you messed with when changing the belt. Try seeing if the you can reproduce the sound while you have the hood popped and revving the truck in Park.

[Italianstln323]

If the sound wasn't there before, than I would definitely check into whatever you messed with when changing the belt. Try seeing if the you can reproduce the sound while you have the hood popped and revving the truck in Park.

I can reproduce the sound. I checked the Idler pulley/tensioner assembly when the vehicle was off, and there is about 1mm of wobble at the pulley. (see pic) Is that a normal amount of play, or could that be the culprit and it may be causing part of the belt to rub?


The pulley in question is the one in the middle.

[unplugged]

Not a hard part to replace. Take the original off and inspect it closer. You will probably find that there is too much play in the assembly. Your local parts store will have the part. I did the idler on my 93.

[bob13]

I agree, for the cost replace it, but I do not think that is a lot of play in the pulley. Do it first then move on...let us know! Good Luck!

[Italianstln323]

Weeellll. I replaced the tensioner assembly but still heard the sound, so i did a bit more snooping around for anyone else with the same problem, turns out a friend had the same problem on an '01 Tahoe.

From '00-'02, the ac compressors that they put in had defective clutches, so what happens, is when the engine hits a certain rpm band, the ac clutch randomly locks up, causing the tensioner assembly to flail wildly and bang against oil lines, the frame, etc. as the belt pulls tight. GM supposedly released a letter regarding the defective parts, but never issued a recall.......................

So now I know its the compressor clutch, but my question now is, should I simply have it rebuilt with a new clutch, as it still blows cold, or should I just bite the bullet and buy a ramanufactured unit and pay to have it installed? Also price wise, what would be a decent ballpark figure?

Thanks again, I appreciate all of the responses.

[KenSuburban]

I have a 2001 Suburban with the exact same problem. The Chevrolet dealer replaced my main clutch fan without any change.

I will attempt to change the A/C compressor clutch and see if that fixes my problem.

[Italianstln323]

Actually this problem is caused by liquid slugging in the compressor, not faulty clutches. What happens is that the compressor struggles to pump the liquid freon back up to the top, (due to the fact that GM decided to put the compressor so low in the bay), and this causes the compressor to shake violently, and rattle the tensioner to the point that it bangs the stop tabs (the source of the sound) I found an online GM Tech who gave this answer:

Condition
Some customers may comment about an underhood rattle noise heard on acceleration or a sudden loss of A/C system performance.

Cause
This condition may be caused by liquid slugging of the A/C compressor. This condition may cause an internal failure in the A/C compressor. The serpentine belt
tensioner and serpentine belt may also be damaged.

Correction
Technicians are to check the A/C system performance and compressor operation using the following repair procedure:

1.) Open the hood and inspect the A/C compressor for damage and to see if the compressor is seized. Verify that the serpentine belt is not damaged or missing. If the A/C compressor is seized, proceed to step 5.
2.) Perform the A/C System Performance test. Refer to the Heating,Ventilation and Air Conditioning (HVAC) section of SI. Correct any performance concerns or refrigerant leaks that are found.
3.) Inspect the vehicle for other possible sources of A/C compressor noise or performance concerns. Refer to Corporate Bulletin Number 01-01-38-013 for more information.
4.) After all other possible sources of A/C compressor noise or performance concerns have been eliminated, only then should the A/C compressor be replaced.
5.) Remove the A/C compressor. Refer to the A/C Compressor Replacement procedure in the HVAC section of SI.
6.) Inspect the transmission cooler lines for damage due to contact from the serpentine belt. Replace the transmission cooler lines if necessary.
7.) Install an inline A/C system filter. Refer to Corporate Bulletin Number 01-01-38-006C for more information about A/C system flushing and filter installation procedures. An A/C system flush is not to be done unless prior authorization is given by the GM Area Service Manager (in Canada, the District Service Manager).
8.) Install an A/C Suction Screen. Refer to Corporate Bulletin Number 01-01-39-003A for more information about A/C suction screen repair recommendations and procedures.
9.) Install a new A/C compressor. Refer to the Compressor Replacement procedure in the HVAC section of SI.
10.) Install a new orifice tube for the front A/C system. Refer to the Expansion (Orifice) Tube Replacement procedure in SI.
* If the vehicle is a 2003 model yearChevroletExpressor GMC Savana van, the vehicle may require a new accumulator. Refer to Corporate Bulletin Number 03-01-38-016 for more information. This bulletin refers to an updated design accumulator that may improve the performance of the A/C system.
Install a new serpentine belt tensioner and serpentine belt if they have been damaged due to A/C system slugging or an A/C compressor seizure. The serpentine belt tensioner may have broken stop tabs and/or a missing front cap.
Verify proper operation of the A/C system.
Parts Information
Refer to the GMSPO parts catalog for the latest service replacement compressor part numbers.

Part Number
Description
Qty

89016656 (*A/C Delco Part# 15-10413)
Universal In-Line A/C Filter
1


Parts are currently available from GMSPO.

*This filter may also be purchased through your local A/C Delco distributor.

Warranty Information
For vehicles repaired under warranty, use:

Labor Operation
Description
Labor Time

D4440
Compressor Assembly - Replace
Use published labor operation time

This is the information I was able to get from the TSB on the problem:

Make : CHEVROLET Model : TAHOE Year : 2002
Manufacturer : GENERAL MOTORS CORP.
Service Bulletin Number : 030138019

Replacement Service Bulletin Number: 030138019A Date of Bulletin : SEP 01, 2004
NHTSA Item Number : 10005551
Component : EQUIPMENT:ELECTRICAL:AIR CONDITIONER
Summary :
UNDERHOOD AIR CONDITIONER RATTLE NOISE HEARD ON ACCELERATION OR A SUDDEN LOSS OF AIR CONDITIONER SYSTEM PERFORMANCE. *TT THIS BULLETIN REPLACES 03-01-38-019 DATED 11-01-2003. TO INCLUDE VARIOUS MODLES INCLUDING 2002-2004 COMMERCIAL UPFITTER CHASSIS VEHICLES. *TT