A6 Compressor oil viscosity?

[Larry M.]

Re: A6 Compressor oil viscosity?

So 100 viscosity is OK for these compressors, that's good since I have a bunch.

I understand the problems with the idea of a clean system. I just finished re-sealing my compressor with the correct seals, I have no refrigerant lines so they'll be good for 134a, all o-rings will be compatable, I'll use this (http://www.nucalgon.com/products/tsp/rx11-flush) to flush the condenser, TXV (It's operation ios a wild card) and evaporator since they are the only parts that came with the car and I'll deal with the POA, I have a P/T chart. Just tried to bench test the POA but it's stuck open, I'll be dealing with it. And since 134a is pretty cheap (About 150 for a jug) I'll have it for a while.

Europe has recognized that 134a is a really bad greenhouse gas. It will everntually go by the wayside but like all refrigerants it will get replaced by something. Been there, done that.

The TXV can be tested (somewhat) by checking if the restriction thru the valve is increased (flow thru the valve reduced) when the TXV bulb is is immersed in an ice bath. This at least gives you an idea of whether it is DOA or not. Having the POA stuck open is better than having it stuck shut They can be repaired by a few AC places.

I check the evaporator putting a bit of refrigerant into a closed system and using a refrigerant leak detector. Blower speed on LOW or Medium. If a leak, the "sniffer" should show it when held up to the AC ducts. A standing vacuum check of the system could also tell this as well…….especially if you use a micron vacuum/pressure gage…..and the deep vacuum holds.

I have heard that the switch to R1234yf has more to do with royalties and new patents than greenhouse gas or ozone depletion. I don't know all the facts, but if a lot of $$$$$ is involved, well…………….

Experience with the R12 and R134a systems during the last ten years or so, indicates that the mineral oil from the R12 system will coat the inside of the old hoses and make then impermeable to the smaller 134a molecule. But barrier hoses are probably still best in the long run.

Larry