How much oil to add to AC compressor?

[Kebo33]

I have taken the old compressor off.......but since the housing had a leak there is no oil in the compressor to see how much I should add back. The manual doesn't specify how much to use and the sticker under the hood just says to use synthetic oil......so how much should I add back in to the compressor before reinstalling? I am also replacing the dryer.

Thanks,
Kebo

1999 Chevy Blazer LT
4.3 V6 2WD

[billibong]

Are you replacing the compressor, or just reinstalling the old one?? For a new compressor I added one small can of oil - 4 oz? - and two cans of r 134a, 12 oz.

[blazee]

I would suggest a complete refill, because after a compressor body leak, you can't be sure how much oil is still in the system. You should install a new orifice tube, too, that way when you remove the old one any oil in the evaporator will drain out too. When you put it back together use "PAG150" oil in the pour bottle. Spread it out by pouring it in different parts of the system. Add the majority to the compressor and turn it by hand to allow the oil to coat everything. You don't want the compressor to dry start under load.

[Kebo33]

I am installing a new one.......I tried to find a place to rent a vacuum pump but no one seems to rent those. I read another post that said to use 8oz. 6 in the compressor and 2 in the dryer. Any thoughts? And if you didn't pull a vacuum, how well does your system work?

[billibong]

I did have a friend pull a vacuum on the system, to make sure it was completely evacuated. I replaced the orifice tube, also. You definately should, because if you don't the warranty is void on your new compressor.
I used the PAG150 oil and did like blazee suggested, it might have been an 8oz bottle. I used the resources I found on this site to do it right. Quite a few of these guys have a lot of hours under a hood, more than I do.

[Kebo33]

Ok, I have the compressor and the dryer changed out.....but the manual doesn't tell me where the orifice tube goes. Can anyone help me out?
Thanks, Kebo

[blazee]

It's in the line where it enters the bottom of the evaporator.

[Kebo33]

Originally Posted by blazee

It's in the line where it enters the bottom of the evaporator.

Let me guess.....that is under the dryer going into the airbox? If so, that will be a "mother" to get to.

[blazee]

Its not bad. The evaporator is in the black box on the firewall,, but the line connects outside of the airbox. Just remove the line and the orifice tube is stuck right in the tip of the evaporator.

[chcknugget]

Where did you get your new compressor from? I have to do all this soon as well.

[Kebo33]

Originally Posted by chcknugget

Where did you get your new compressor from? I have to do all this soon as well.

I got the compressor, dryer, and orifice tube at Advanced Auto Parts. I think the total was $335. The compressor was a rebuild with a 2 year warranty. You can find them online at www.partsamerica.com.

[stuckryan]

question on the process
ive read to pull vacuum before charging it
if i put oul in the compressor and pull vac wont that pull the oil i put in out ?