Air Condioning Help

[airemdwn]

Im doing a complete overhaul on the A.C. in the 91 Blazer. All new components except for the Evaporator which was flushed.

Am i correct in using Ester oil and not PAG for the retrofit to 134a?

How much oil should be used in the system? I cant seem to find that information anywhere. The sticker says 3 lbs. of r12 and i know it will be roughly 80-85% of that to fill, but how much oil for a basically new install?

 

[AZ79K5Project]

The compressor should be pre-oiled. The accumulator (if new) takes 2 oz if memory serves me correctly.

Autozone has cans of R134 that contain oil, leak detector and refrigerant.

 

[89GMCK5]

I thought that you were supposed to use the PAG oil with the new R134 stuff........ I know they sell the small cans of R134 with PAG oil, leak sealer, leak detector, etc. all at the counter at the parts house.

 

[mudbuggy]

If you have a new compressor, chances are it is shipped dry to avoid situations with the EPA. That is how my was shipped, and I assumed that they oiled it at the factory. I called the tech line for Compressor Works and asked them why no oil came out from tipping it upside down and the techs reply was that it was lubed at the time of assembly, but it was shipped dry to avoid having to pay a premium to the EPA as a 'enviromental fee' for every compressor. So to save money they do that. I was also inquired about the amount of and type of oil for the system. I was told that the compressor works 'pancake style' a-4 will be quieter with PAG 150 oil, dump in 2-3 ounces and leave face down for a few minutes. Install the cap, then install the compressor on the truck. Break open the lines to the big silver thing on the left that is right after the compressor following the line (can't remember the name of it right now) dump the remainder of the 8 ounces of oil into it. Then vac it down for 45 minutes. This is for the Compressor Works new pancake style compressor.

 

[AZ79K5Project]

Ultimately you need to determine if your compressor was shipped dry. The last two I purchased were shipped already oiled. Compressors are tagged indicating either to add oil or not to add oil.

Here's a couple of links to some good information from ACDELCO:
http://www.acdelcotechconnect.com/pi/ac/lubrication.htm
http://www.acdelcotechconnect.com/pdf/pi/oil_balance_card.pdf

COMPRESSOR OIL BALANCE REQUIREMENT

NOTICE: This compressor is shipped with some refrigerant oil. It may NOT be sufficient for system needs. Prior to compressor installation, adhere closely to the following Compressor oil requirements:

1. Prior to installing the replacement compressor, drain the refrigerant oil from the removed compressor into a calibrated measuring container. Record the amount and discard old oil.

2. In a clean measuring container, drain the oil from new compressor. Turn shaft several times & if equipped, remove oil drain plug to assist in draining. (Rotation torque should not exceed 70ft/lb)

3. If oil amount removed from old compressor is less then 2.5 oz. add 2.5 oz of universal oil back into new compressor (May reuse oil removed from new compressor). If amount removed from old compressor is greater then 2.5oz. Add the same amount of universal oil to the new compressor as drained from the old compressor.

Note: If additional system a/c components are being replaced, follow the system oil balance schedule with universal oil detailed below.

SYSTEM OIL BALANCE REQUIREMENT

NOTICE: Vehicle A/C systems require a given amount of lubricant dependent upon OEM manufacturer and model. Reference total system charge from vehicle tag or service reference material. It is important that if system is flushed or components replaced, the amount of overall lubrication charge is maintained.

1. These components require oil addition prior to assembly:

Evaporator core - add 1.5 oz.
Condenser core - add 1 oz.
Hose/Muffler assembly - 1 oz.
Accumulator - Drain & measure oil from removed accumulator: then add same amount plus 2 oz. of new refrigerant oil to new accumulator
Receiver/Dryer - Drain & measure oil from removed receiver/dryer then add same amount plus 1 oz. of new refrigerant oil to new receiver/dryer

2. If System/Component Flushed - refill system to its total capacity. If one component(s) flushed, add oil amount equal to replacement amount detailed in item#1 above.

Note: Failed compressors deposit debris throughout the system. No flush completely removes all debris. ACDelco highly recommends the installation of a COMPRESSOR GUARD SUCTION SCREEN to protect compressor and an in-line filter to protect TXV's. Installation of A/C leak dye is also recommended as well as a final leak check.

 

[Big Ray]

Before you buy a stock compressor, read this thread...

 

[K5 Jess]

M

Before you buy a stock compressor, read this thread...

That thread is awesome! Thank you

 

[Big Ray]

M
That thread is awesome! Thank you

all part of the service....