PAG AC Oil Questions

[FordGuy100]

So I pulled my AC pump off in preperation of converting over to R134a. I went to go and drain the old oil out of the AC pump and......nothing????

Front of the AC pump, the clutch area, has been covered in a oil film for a long time, suppose its been leaking out there? If so, do you think the pump is toast? I guess I wouldnt want to reuse it if its leaking out the oil anyways as regreigerant would also leak out, at least thats what my logic tells me.

So, is the pump toast, do I need another? I've seen oil come out of AC compressors before, and I hear it just sits in the bottom of it. But I turned this one over, and turned the pump by hand and nothing.

Need to know soon, will be borrowing a vacuum pump in the next couple days.

 

[SparkandFire]

If the compressor is leaking from the front seal, there's no sense in putting it back on, most likely there is a major leak point there.

Most of the oil in our systems is actually in the form of a vapor/fine mist that moves throughout the system with the refrigerant, so there will most likely be a very small amount of oil actually living in the compressor.

I would plan on tossing a rebuilt compressor on there, you definately don't want "black death" sneaking up on your freshly converted system!

And change the dryer/orifice tube while you've got it apart... Spring for the high ambient temp rated orifice, you'll be much happier with that!

 

[FordGuy100]

I have a new dryer and I'm putting in a high temp VOV in right now, I'm just worried about the AC compressor. Damn they are so expensive too......

 

[SparkandFire]

For what it's worth, my brown truck had alot of oil around the bottom end of the compressor. I traced it down to a leaky PS pump slinging the oil all over the place.


Worst case scenario is you bolt it up, put it under vacuum and find it won't hold...

If you put enough hybrid/retrofit AC oil in the system when you recharge it, it might be ok.

I would either hold out for a rebuilt compressor, or run it as is, depending on how hot it is there

 

[FordGuy100]

Its 90*+ and the humidity is around 70% as we had 8.5" of rain two days ago.

 

[SparkandFire]

Well then, you could try it and see if it holds vacuum.

It may, or may not last

 

[cetanefreek]

like SparkandFire said, put the system together and pull a vacuum on it, close the valve and shut off the pump, leave it for an hour or two and come back and check, you'll know if it's a leak pretty quick.

 

[FordGuy100]

Alright, thanks for the advise guys . Which oil is compatible with both the oil that came with my R12, and the new oil?

 

[RLDSL]

If you need a compressor, don't fool with a used or repainted one. Get a new one. THey are usually cheaper anyway. I get all my compressors from Jon at www.nostalgicairparts.com Last one for a ford truck was about $220 I think I've never had one of his compressors fail.
You don't have to worry about old oill in the system as R134a will not absorb mineral oil so any old mineral oil that remains in the system will just find a low spot and sit there, but it is best to flush it out as best you can. As said the compressor doesn't have a sump, the oul gets absorbed by the refrigerant and passes through the system as a mist and lubricates the pump and whatever otehr moving parts along the way