dr bob

The original oil in the compressor is mineral oil (not the medical stuff). Get that out before you try to add a different oil to the system. Pull the compressor out completely so you can replace the manifold plate o-rings, and while it's out you can drainthe oil oil and flush with new a few times. The add the proper amount of new oil for the whole system. You must change all the o-rings in the system if yuo use polyolester oil. ALL of the o-rings. With the new oil in the compressor, turn the compressor by hand in the installed system, maybe 50 rotations, so that there's no chance that you have filled a cylinder with liquid. Put the belt on, install the drier, seal everything up, and pull a good vacuum on it overnight. Check the next day that vacuum is deep enough that all moisture is boiled out, verify that there are no serious leaks by stopping the pump and watching the torr gauge. Then charge with liquid by weight. Let the car sit for a few minutes to make sure there is no liquid left, sniff with a leak detector. If all is OK, start the car and verify function.

Speedtoys

Well, hes NOT gonna replace those Orings, been thru that.

And..why cant he add more of the same oil, since he's not changing refrigerants?

rgs944

There is a actually a good chance I did change those out already so I might be doing it twice. It has been a while but I have it in my mind that the lines going into the compressor were all resealed. So maybe I did drop the compressor if that is what needed to be done. I would assume if it holds a good vaccum it should work when charged if all the electronics are in order. The oil I have is call Esther 100 from Napa. It says it is a synthetic that is compatable with R12 and R134. Do I need to drain all oil or do you think this will work.

Speedtoys

Its not too hard TO drop it, belt comes off easy, two bolts hold it up at the top..one in front, one in rear. And four allen bolts hold on the plate with the lines.

Four HUGE Orings are under that.

If they are original, sure it could work fine, but..you may end up back in there in a few weeks of re-use.

I dont have the answer on the oil.

I dont recall the size of the Orings under the plate, maybe..19mm? All 4 are the same size.

rgs944

I just wish I could remember exactly which seals I did. Let's assume I did all the seals on the compressor. Would all of the oil drained out at that point?

Speedtoys

If you removed the compressor..you would have then simply turned it over..and poured it out.

rgs944

I believe Dr. Bob that I may have the wrong stuff. It says it is compatable but I guess I would rather just put the mineral oil back in. Can you still buy it or is it like R12?

928 at last

Your'e in Nebraska, Not sure where, but in farm country, there are any number of independent mobile guys that repair and maintain farm equiment...including the A/C units in the combines and harvesters...most will have a decent vacuum pump...may be closer than you think..

rgs944

I feel confident that I will be able to find a vaccum. This oil thing has really got me stumped though. Did they outlaw mineral oil too? Advance auto said they do not sell it.

AirtekHVAC

Found some, but don't know stock levels. It is still available at most AC parts houses.

http://www.summitracing.com/parts/FSS-59000/

rgs944

I talked to a local service tech and he did say that they use the Poly Ester when they convert to 134. He basically said the same thing as the bottle says. The new formula is compatable with the original oil. According to him when 134 first came out they made them drain all the oil completely when converting but now they tell him that is no longer needed with the new stuff. The next thing is a vaccum. Has anyone ever made one? I called the local auto places and none of them had any for rent. I really do not want to take the car to a shop if I can figure out someway to vaccum at home.

rgs944

I found a great demonstration video. Anyone that uses the word gizmo talks in language that I can follow. lol ... Now if I just had the $80 vaccum pump?

ammonman

There isn't any way I know of to create the deep level of vacuum necessary short of a deep draw vacuum pump. There is a device that uses compressed air to create the necessary level of vacuum but few folks will have access to a compressor that will supply the required volume and pressure for the amount of time required to generate the level of vacuum needed. If you are anywhere near Lincoln or Omaha you can pick up a fair vacuum pump at Harbor Freight for $100, less if you have one of their 20% off coupons.

Mike

Speedtoys

Ya..a good 2 stage vacuum pump is $150ish.

rgs944

I do have a 60 gallon 6.5HP compressor. Is that strong enough, and if so does anyone know where can I find a compressed air vac? I guess I will look on Ebay.