AC compressor replacement

[Falcon_LS]

I'm going to be replacing the failed AC compressor on my Avalanche before the weather starts getting any warmer. Other than the compressor itself, is there anything else I should consider replacing? At the moment I just have the following on my list:

- Compressor
- Receiver dryer
- Orifice tube
- O-ring and gasket seal kit
- Cabin filter

Is the condenser worth replacing along with these? Also, I kind of feel ACDelco products are going downhill quality wise, are Delphi parts worthwhile alternatives? Although it seems Denso is GM's OE supplier for the compressor. Thanks!

 

[Trav]

I would probably replace the condenser after a compressor failure,they are real trash collectors.
Its possible to flush them but unless you get everything it can cause a repeat fail.

Don't forget oil for the compressor,make sure you get the correct type and weight.follow manufacturers recommendations for filling and amounts to the letter.
Do not use refrigerant containing additional oil sealers.

 

[Falcon_LS]

Trav, thanks very much! The condenser is added to the list.

The ACDelco compressor comes fill with oil, although I'm not too sure about the Delphi unit I was looking at. Thanks for pointing that out, will double check before buying anything.

 

[Trav]

Never trust when when they say pre filled.I got a brand new one and it had about 1oz in it instead of 3oz.
I believe yours spec PAG 135 or 150 but double check.

 

[Chris142]

Pull the Orifice tube first. If it's clean then you don't need a condensor. If it's dirty you need a condensor.

 

[Merkava_4]

Originally Posted By: Chris142
Pull the Orifice tube first. If it's clean then you don't need a condensor. If it's dirty you need a condensor.


What you do is replace the orifice tube, then you back flush the condenser with de-natured alcohol using a back flush kit. Just fill the tank up with de-natured alcohol, hook it up to the air hose, then spray the alcohol through the condenser in the reverse direction of normal refrigerant flow. It's real easy.

 

[Falcon_LS]

Originally Posted By: Trav
Never trust when when they say pre filled.I got a brand new one and it had about 1oz in it instead of 3oz.
I believe yours spec PAG 135 or 150 but double check.


Is there a way I can find out for certain?

Originally Posted By: Chris142
Pull the Orifice tube first. If it's clean then you don't need a condensor. If it's dirty you need a condensor.


Unfortunately the tube isn't clean. Will go ahead and replace it, should probably last a long time.

Originally Posted By: Merkava_4
What you do is replace the orifice tube, then you back flush the condenser with de-natured alcohol using a back flush kit. Just fill the tank up with de-natured alcohol, hook it up to the air hose, then spray the alcohol through the condenser in the reverse direction of normal refrigerant flow. It's real easy.


Thanks! Would there be any benefit of doing this with a new condenser going in?

 

[Trav]

There is a drain plug on the compressor.Remove the plug and measure how much comes out,if it has about 3oz just put that amount back in its filled properly.
If only very little comes out fill to manufacturers spec.
Chances are if its claimed pre filled its okay but personally i rather confirm than wreck a new unit,i sleep better.

IMO it cant hurt to flush everything remaining in the system if possible even when replacing the condenser,it cant be to clean.

 

[Falcon_LS]

Trav, thanks very much! I completely agree, better safe than sorry.

Will also flush out the system, thanks for pointing that out, Merkava_4.

Does it mention whether PAG 135 or 150 should be used for the compressor? Couldn't find any mention of it in the service manual.

 

[RH+G]

Define failed?

 

[Trav]

look at this chart.I would say it takes PAG 150 i did a 2001 GM and that's what it took.

http://www.aa1car.com/library/pagoil.htm

 

[Falcon_LS]

Originally Posted By: RH+G
Define failed?


I bought the vehicle from a friend. The AC doesn't blow cold air, doesn't make a difference whether you use vent or turn the AC on, and the compressor leaked oil. I reckon the leak was what caused the failure.

Originally Posted By: Trav
look at this chart.I would say it takes PAG 150 i did a 2001 GM and that's what it took.

http://www.aa1car.com/library/pagoil.htm


Thanks a lot!

 

[Trav]

Falcon look at the new compressor if its a Denso it may need PAG 46 look at the chart,150 for the Delphi or AC Delco.

I usually keep some 46 100 and 150 on the shelf,in your case if you order it at the same time as the unit get a can of both.
Its inexpensive and wont bring the job to a halt by not having the correct oil.

PM with the compressor type number if you need help finding right stuff.

 

[Chris142]

Originally Posted By: Merkava_4
Originally Posted By: Chris142
Pull the Orifice tube first. If it's clean then you don't need a condensor. If it's dirty you need a condensor.


What you do is replace the orifice tube, then you back flush the condenser with de-natured alcohol using a back flush kit. Just fill the tank up with de-natured alcohol, hook it up to the air hose, then spray the alcohol through the condenser in the reverse direction of normal refrigerant flow. It's real easy.

His truck has a paralel flow condensor and you cant effectivly flush those out. Must replace if it's contaminated. The old style serpentine condensors can be flushed.

 

[onion]

+1

 

[MarkM66]

I used one of those flush solvent kits to flush the evaporator, and lines/hoses.

I replace the comp. dryer and condenser.

 

[JHZR2]

Depends upon how it failed. You might have junk in there if it self-destructed. If so, additional flushing/replacement is necessary. At minimum, plan on comp and rec/drier, with as many orings as possible.

 

[Merkava_4]

Originally Posted By: Falcon_LS

Thanks! Would there be any benefit of doing this with a new condenser going in?


No ... the procedure is for cleaning out your existing condenser.

 

[wtd]

If you have a lot of debris on your OT, I would replace the condensor vs trying to clean it. Some condensors due to their internal design are almost impossible to clean. Also if any of your AC lines have built in mufflers, I would replace those as well. If you do use a flush to flush out anything in your system, make sure you get it all out or you can ruin your new compressor. I also always drain out a new compressor if it has oil in it and refill with new oil at the correct capacity. That way you know you have the right amount.

There is a product called Nylog which I use to coat all my O-rings and connections which helps the line connections from seizing up and will help seal these areas as well.

The thing with AC repair work is do the job right the first time so you don't have to keep doing it again. Also having the right equipment such as high and low side gauges and a vacuum pump, will make a big difference in how the repair comes out. Good luck

Wayne