just got a call from the shop. my Mazda's ready. I'll come back and post the results for comparison -- I know it's not an apples to apples, but it's an R-12 to 134 conversion, so if anyone's interested in a "professional" result...
okay, so on the drive home tonight, about 7pm, outside temp around 72*, 57% humidity, I was getting 49-52* output at the vents on the '87 Mazda 626 that I had retrofitted at the shop.
The oil is throughout the entire system. A lot of it lives in the compressor, but there's plenty in the condenser, the evaporator, and even the lines, especially where they droop down. The compressor is not like a 4 cycle car engine where there's a sealed and seperate crankcase. It's more like a 2-stroke engine, where everything goes through the crankcase.
You will not get the oil out by vacuum. All that does is pull out everything that boils at low pressures. To get the oil out, you've got to manually remove components and drain them. Tedious, to say the least. But if all you do is the compressor and condenser, you've got most of the oil.
okay, this makes perfect sense now. I just wanted to make sure that evacc'ing the system doesn't pull out the oil I'd be pouring in.
speaking of boiling at lower pressures -- water at -30" -- is it hot, or does it boil cold?
I got my oil from the A/C-kits.com listed above in the thread. BVA auto-100 (I went and looked).
okay, I think this is the same as the Ester oil. and for the comments above, the can of Ester oil says that it's compatible with the chlorine residue of R-12 refrigerant oil, and that it's compatible with other auto refrigerant oils.
It surprised me how much difference the oil change made. I wouldn't have done it except the replacement oil was quite cheap.
yeah, I'm really curious about this now. it's been bothering me since I retro'd it. I'd like to think I'd have burned it up by now were it not getting the lubrication it needs, though, but I feel better with the oil & refridge separate, I think. don't know why; I'm just a stickler for detail and doing things properly.
In the junkyards you will find many electrical solenoids and such that can be fitted up quite easily to your Weber. I'd consider it a worthwhile upgrade, but you can do the job with your foot.
I wouldn't mind finding something like this, but I wouldn't even know where to begin looking or how to go about rigging it up. any addition info would be greatly appreciated.
thanks for all the information here guys. this has answered a lot of my questions.
