AC issue on the wifes suburban

spareparts · #1 05-12-2014, 08:21 PM

Give me the bad news, wifes 02 suburban(with rear air) is throwing the belt. System was cooling fine. I haven't discharged the system and its holding pressure fine. I searched on line and keep coming up with "Slugging" Tell me what need to know to get this fixed. Compressor? Dryer of course, "the 4 seasons "slugger" ? Return line screen?

THEFERMANATOR · #2 05-12-2014, 11:39 PM

Is the tensioner for it still good? Are you putting the old belt back on it or a new one? The new style compressors really don't give much trouble unless stop leak gets introduced into the system. If you do need a compressor, I wouldn't go for a 4 seasons myself. I buy all of my A/C stuff from MARKS AIR. He's local to me, and carries what works(not just what he can make money on).

Just did some searching and seen where peopel have complained about it. It's odd because I have never heard of anybody around here complain about it. I would go for a GPD compressor myself. ROCKAUTO now carries them, or you can call MARKS and they will get you a kit with everything you need to do the job out to you.

smokeonthewater · #3 05-13-2014, 06:07 AM

My first thought is idler pulley

spareparts · #4 05-13-2014, 06:24 AM

already replace the idler and belt. Ran for a few then kicked the belt off when I hit the gas

smokeonthewater · #5 05-13-2014, 08:21 AM

I think I'd do the tensioner next

http://www.autoacforum.com/messagevi...threadid=12491

spareparts · #6 05-13-2014, 07:10 PM

got the idler with a tensioner

Destroyer · #7 05-13-2014, 08:14 PM

I may just be stating something that you already know, but slugging a compressor is when you introduce a "slug" of liquid refrigerant into the compressor itself. Since liquid is not compressible, it causes the compressor to lock up. If the compressor is locked, then the belt will usually either fly off or break. Sounds like that is what the book is talking about. Eventually the liquid will usually turn back into gas, and the compressor will return to proper operation, making it look like the problem was someplace else. An overfilled system is usually the cause of slugging, but I have seen cases where the air passages in the evap coil are so clogged with hair or leaves that the the hot liquid cannot completely boil off in the evap coil and so it returns as liquid back to the compressor.

THEFERMANATOR · #8 05-13-2014, 08:18 PM

Quote:

Originally Posted by Destroyer

I may just be stating something that you already know, but slugging a compressor is when you introduce a "slug" of liquid refrigerant into the compressor itself. Since liquid is not compressible, it causes the compressor to lock up. If the compressor is locked, then the belt will usually either fly off or break. Sounds like that is what the book is talking about. Eventually the liquid will usually turn back into gas, and the compressor will return to proper operation, making it look like the problem was someplace else. An overfilled system is usually the cause of slugging, but I have seen cases where the air passages in the evap coil are so clogged with hair or leaves that the the hot liquid cannot completely boil off in the evap coil and so it returns as liquid back to the compressor.

The problem seems to follow dual A/C units and GM's idea of not routing the low side line from the rear evap into the accumulator before the compressor. For some reason GM ran the rear air return straight to the compressor which is where the problem stems from. ALOT of compressors from 92-95 were lost because of liquid getting returned to the compressor and slugging it before GM came out with a revised expansion valve for the rear A/C unit. The big problem comes into play with people not turning on the rear A/C units fan, this is what allows the most liquid to hit the compressor.

Destroyer · #9 05-14-2014, 08:38 AM

Quote:

Originally Posted by THEFERMANATOR

The problem seems to follow dual A/C units and GM's idea of not routing the low side line from the rear evap into the accumulator before the compressor. For some reason GM ran the rear air return straight to the compressor which is where the problem stems from. ALOT of compressors from 92-95 were lost because of liquid getting returned to the compressor and slugging it before GM came out with a revised expansion valve for the rear A/C unit. The big problem comes into play with people not turning on the rear A/C units fan, this is what allows the most liquid to hit the compressor.

Yep, that will do it. Hard to believe they didn't run the rear back into an accumulator.... but then again, this is an automotive maker, and they (all of them) are known for pinching a nickle until the buffalo sh!ts.

THEFERMANATOR · #10 06-27-2014, 09:05 AM

I was just talking with a friend of mine who runs a shop and he has been having alot of these of late. He said that replacing the compressor wasn't fixxing them, but using a belt off of an 09 is working. He said in 09 GM did away with the tensioner, and went to a stretch belt. You take the compressor loose, slide the belt on, and then tighten it back down. He said that this has fixxed every one so far without a compressor or tensioner change.