# repairing auto a/c, how much oil?



## raylo32 (Nov 25, 2006)

I have an older Camaro (uses R134a) that mostly just sits and it developed a leak over the winter that discharged the a/c. I did a leak check and found a bad service port schraeder. I have done several auto a/c jobs starting from the ground up with new major components (compressors, condensers, etc) and flushing so I know how to find the oil and refrigerant capacities and do the work. But in a case like my Camaro where I am just replacing the leaky schraeder and receiver/accumulator how do I determine how much oil to add? System capacity is 8 oz of PAG 150 and while I am sure some leaked out with the refrigerant how to tell how much remains? I really don't want to pull the compressor to drain off and measure the oil and flush the rest of the system. I don't need a whole day's work. Is there a rule of thumb to guestimate how much oil to add?


----------



## 1985gt (Jan 8, 2011)

I doubt enough leaked out to cause any problems. My wifes old car would need charging every year and I only put oil in it once. 

If your really want to buy the 134 with a oz or two of oil in it.


----------



## raylo32 (Nov 25, 2006)

Sounds good. I didn't see much evidence of oil residue near the leak.


----------



## ukrkoz (Dec 31, 2010)

Truly, if you had a leak, you need to evacuate and clean and recharge the system. But that's me talking.
Otherwise, simply pump in OIL-freon mix. How you will pump it in it's your to determine.


----------



## WyrTwister (Jul 22, 2013)

If you are replacing the accumulator , measure how much it holds . If you add more new oil than that , I would only add 1 more ounce .

It probably uses PAG oil with a GM car .

God bless
Wyr


----------



## WyrTwister (Jul 22, 2013)

Also , if it still had a little pressure in the system , moisture would not have gotten in .

Schrader valves are a fairly common source of leaks .

God bless
Wyr


----------



## Brainbucket (Mar 30, 2015)

I would charge it. Evacuate if you can but just charge it. I starve A/C systems of oil and they work fine. Too much oil and it won't cool properly and of course too little is bad also. If it still had pressure in the system I wouldn't change the accumulator either unless the system was open and you can vac it down. But if you want to know how much to put in, it would be 1 to 2 oz of 150 pag oil for replacing the accumulator. If no parts were changed, charge it with no oil. :thumbsup:


----------

