Does the a/c compressor need any lube?

[Lof8]

I bought some fittings to connect my e30 a/c lines to the e36 a/c compressor and plan to undertake the task soon now that summer is sure here in FL. My Dad warned me to figure out what kind of lubricant to add to the system.

Is anybody familiar with this? He says its usually in addition to the freon or whatever refrigerant is used.

Name? Source? Volume to use?
thanks

[brian90]

If you are going to use R12 you need mineral oil. If you plan on using R134a then you don't need any lube. You will need a retrofit kit for the lines if you are going to use R134a ($10 at Pepboys). I would vacuum the system out, make sure it is empty with everything even air. Then install the new freon and your set to go. For the amount on my 318is it calls for 2.15lbs of R12 but if you are doing R134a you want to do 85% of the witch is 1.82lbs. I don't know what the E36 compressor requires so I would check on that. If you have anymore questions just ask. I'm just finishing up a class on A/C right now. Good luck.

[E30_80Y]

yeah florida summer is gonna be crazy this year. i got my compressor already, just need to figure out the lines and couplings. even with the R134a i think it needs lube, on my nissan maxima the shop added lube after vacuuming out the system and then filled it up with the freon or whatever.

[sharky]

you need to put PAG oil in the compressor, will say what type and how much on the back of it.

[scottinAZ]

regardless of what system refrigerant you are running, you need oil. If the original system was R12, then mineral oil is appropriate, if you have an original R134 system then PAG is appropriate, however, you most likely will have a hybrid system, and that takes an ester oil. this is compatible with both R12 and R134a, and more importantly the oils that are residual in both systems. the amount of oil should be between 5-7 ounces for a totally empty system (which yours is not). If replacing major system components, such as compressor and reciever drier (both hold the majority of the oil) then I would add about 4-5 ounces of oil total to the system. If performing a system flush with new components, then add the full amount of oil to the system

[sharky]

really, i havent hooked mine up yet but will be soon, do you add the oil directly into yhe compressor?

[scottinAZ]

if the compressor is shipped dry, I would add some to the compressor directly (about 1/2 of the total amount, the rest into the reciever drier), this will protect the seals on start up. Make sure you cycle the compressor through about 10 turns or so to prevent a hydraulic lock situation though. There should be a label on the compressor as to whether it has oil in it or not.
I typically will drain a compressor that has been shipped with oil, mostly so I can verify that there IS oil in it, and also what type and quantity has been installed. Compressors are too damn expensive to not do this in my opinion

[Lof8]

I have a used e36 compressor. Do you recommend draining it first, then adding the mineral oil? How much should I add for just a dry compressor? The rest of my system has been sitting "open" for almost a year.

[brian90]

Yeah sorry I just checked I did my a/c today and found out the machine I used lubes the system by itself oops sorry. The compressor should say how much you need to use on it but for the whole system that I'm not sure of.

[scottinAZ]

I have a used e36 compressor. Do you recommend draining it first, then adding the mineral oil? How much should I add for just a dry compressor? The rest of my system has been sitting "open" for almost a year.

if the system has been open, then I reccomend a full system flush to clean out any accumulated shit in there. Then a new expansion valve, and reciever/drier/ As for the compressor, I would definitely drain the old oil and have a look at it. if it looks grey or dirty, I would strongly consider it a core only, and get a new compressor. If you are running with R12, then fill it with mineral oil, the reccomended amount should be available online, as it depends on the type of compressor, but most BMW systems take between 5-7 oz of oil. this can be added two ways, either before system charging, or during, if you have the right equipment. I charge mine beforehand, as I can strictly control the amount of oil in the system that way, and can prevent a slug of oil from fucking the compressor up if it gets in there (whole non-compressible fluid thing) any extra oil on the discharge side will accumulate in the reciever drier, and will be circulated as needed, so no worries there.

[hoveringuy]

R134 in the e30 sucks. The condensor just isn't big enough for it. Try to keep R12. I used Duracool and was very happy with it.

[Lof8]

R134 in the e30 sucks. The condensor just isn't big enough for it. Try to keep R12. I used Duracool and was very happy with it.

even with e36 compressor?

[TrentW]

/\Have a similar question--don't want to threadjack--but what E36 compressor is made to use R12? Last season had my system charged w/R12 for the first time and blew nice and cold, but my compressor (Denso) has leaked out green dye all over it and no more cold a/c now.

The reason I ask this is a buddy has two supposedly good E36 compressors he'll sell me cheap. Or should I buy a rebuilt one for the E30?

Of course I'm replacing the receiver dryer also.

[scottinAZ]

the compressor isnt going to do anything about the performance, and I have to disagree about 134 not being sufficient. I run the old bosch wingcell compressor in a stock system (except for the expansion valve, which is 134a calibrated) and get sub 35 degree air out of the vents on demand. this performance is on par with most other systems out there.