Automotive Air Conditioning Information Forum

northbay wrote: ↑Mon May 20, 2024 6:33 am ok, I'll replace all of those parts and the suction/discharge line as it does have mufflers.

Sounds good.

northbay wrote: ↑Mon May 20, 2024 6:33 am I'll flush the evaporator and its lines. I definitely want to do it right and not have to go back into it later so I don't mind spending a little more for a better chance at success.

Nothing worse than having to do a job over because of problems that one could have taken care of the first time

northbay wrote: ↑Mon May 20, 2024 6:33 am On the oil, I understand the idea of draining the old compressor and accumulator and putting back in the same amount on new parts. But what about the condenser, it should also have some oil in it & I can't drain that to see how much? What about the evap? Once I flush that, no way to know.

I don't think I clarified sufficiently. Draining and measuring the oil in the ORIGINAL compressor, condenser, evaporator, and accumulator isn't necessary because you'll be replacing all but the evaporator with new parts.

The idea is to start or end-up (depending on which way you look at it) with a completely clean and "dry" system by flushing the existing parts. In this instance, the only original major component remaining would be the evaporator. By flushing the evaporator in situ, the goal is to remove all traces of the old, contaminated oil and any debris that might be lurking inside it.

In addition to the accumulator, the condenser and lines will be replaced with new parts and will be completely empty of oil.

The new compressor often comes from the factory with enough oil already added. In reality, that might or might not be the case. Typically recommended is to drain-out from the new compressor as much oil as you can, and either refill the compressor with the full specification of 9 ounces of PAG-150, or "oil-balance" the system.

GM used the former "compressor-fill" method on the production line, which is easiest. But you can also oil-balance the system if desired.

The procedure for oil-balancing entails adding small amounts to each major component and the rest to the compressor before assembling the system. A good way to do this is to add 1-1/2 ounces to the now flushed-clean and dry evaporator, 1-1/2 ounces to the new condenser, 2 ounces to the new accumulator, and the balance of 4 ounces to the new compressor.

Both methods work well.

…

got the parts and started working. Noticed the new compressor says it has PAG46 in it. But the kit also has an 8oz bottle of PAG150. Should I drain out the 46 and refill with 150?

Interesting dilemma. It sounds like the compressor manufacturer is telling us that it could use either viscosity. Because your car calls for 9 fluid ounces of PAG-150, I suggest draining the PAG-46 and going with the PAG-150, plus one ounce more than supplied in the included bottle.

JohnHere wrote: ↑Sun May 26, 2024 7:57 pm Interesting dilemma. It sounds like the compressor manufacturer is telling us that it could use either viscosity. Because your car calls for 9 fluid ounces of PAG-150, I suggest draining the PAG-46 and going with the PAG-150, plus one ounce more than supplied in the included bottle.

Many of today's suppliers use import compressors. Some are designed to run different oils than the OE model. It would be best to ask the supplier this question. They should know the answer.

That said, PAG150 probably will not harm the compressor.

i finished rebuikding the system and it seems to be working well. Got in touch with comp mfg and he said although draining all PAG 46 oil out & replacing with 150 would work, he recommended staying with 46. I did that and added the remainder to the other components to get to 9 oz total. I had already ordered the parts when I read that ackits.com sells everything I would have needed. On the next one, I'll just order from here.

Want to thank all who responded with suggestions and advice. It definitely helped me & I made a donation to the forum.

Ray

Oil is a little more tricky these days. Once, we could look up OE type and run with it. Will these import versions of compressors it is best to know what they specially use. That's the reason I say know your supplier!! The item might be the same on eBay, Amazon, or our site. It's the follow-up on gets that is important these days.

Good to hear it's up and working.