A/C compressor oil quantity

[Map63Vette]

So wasn't sure whether to post this in the A/C section or here since it's on the new engine, but I'm a little confused on how much oil should go into my system. I got the Classic Auto Air system installed and am using a used A/C compressor my parents got me for Christmas. The compressor is an unknown, so I have no idea if it had the correct amount of oil or not. I drained it last night and it appeared to only have maybe 1 oz or so (40 ml as that's the only measuring device I had handy). Specs online put the capacity at 6 oz, which is way more than came out. I'm not sure if that's whole system or just the compressor though, and I'm also unsure if the CAA stuff comes with any oil already in it either, so any idea how much I should actually be putting in?

 

[67Dart273]

No idea, but isn't there a stamping of some sort? Also, I have not kept up with specific differences, but there may be an oil type compatability issue, depending on what refrigerant and oil you are using vs what the compressor was built for

 

[JDMopar]

I had to have my AC system evacuated in my Dakota a while back, to change the busted heater core. The guy who did it told me to put 2.5 ounces back in it before I put the lines back together. I bought some PAG oil at the parts house and did as he said. Recharged after I got done and it will spit ice cubes out the vents!

 

[RustyRatRod]

6oz is the capacity for the entire system, not just the compressor. You can get a good idea by choosing an application that that particular compressor came on and looking at the oil capacities for that. Generally, when you get a new or reman compressor, the destruckshuns tell you to measure how much oil comes out of the old one and use that amount for the new compressor. There also should be approximate capacities for each individual component in the service manual. There's normally some int he bottom of the condensor, evaporator and a little in the expansion valve and drier, for example.

 

[Darter6]

About a year ago did a retro A/C using Vintage air parts. In the instructions it stated that the compressor comes sealed and has the proper amount of oil.Do not add additional. From what I remember.

 

[Darter6]

Rule of thumb was 1 oz of oil for each component. As changing a condenser/evap/dryer/hoses etc.
Like Rusty stated .

 

[George Jets]

☆☆☆☆☆

 

[Map63Vette]

I did a little more digging and asking CAA and I think I've got a plan going forward. The compressor was bought used from a salvage yard I believe, so I don't really put much weight in any quantities of oil that came out of it and have drained it to treat as "dry" as much as I can. All of the other components in the system are brand new and have never seen refrigerant, so I'm pretty sure they are dry. I asked CAA and they stated that their compressors ship with the correct amount of oil for the whole system, which to me confirms that all the other parts are dry.

It's a Denso compressor by the tag that states the oil type (DP-8 or something like that), which corresponds to PAG 46. The Denso literature statues 5.7 oz, so my plan is to put as close to that as I can into the compressor and hand turn it through the system as I don't really feel like trying to squirt it into every individual component (it will get there on its own eventually). I'll have to see if I have an actual drain/fill plug on the compressor. I just tilted it and drained it out of the refrigerant ports last night to measure things while turning it by hand. Sounds like I should be fine putting the full stated capacity in though, provided I'm careful to not slug the system with liquid on first start.

 

[Darter6]

Now that we know that the compressor is used and have more of the back story you will be fine doing the 5.7/6 oz amount of oil. Also don't worry about ''sluging the system" as after you evacuate and then put the first charge(can or how ever you will be charging) it will move the oil through the system before you even start the car and get the compressor spinning.