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A/c
The most important part of doing a/c work is getting everything clean.
I have replaced many compressors and haven't had any problems. The best way to do it is to take the lines and hoses off the car, if possible. I clean out all the lines with a carburetor spray cleaner (CRC, or Master brands are good-- they dry with no residue) and blow them out with air. Some cars have orfice tubes that look like a screened filter, and others have an expansion valve(a square block w/an inlet and an outlet line). When I replace orfice tubes and expansion valves, I use the ones designed for 134A. The pressures are different than that of R-12, which makes the system cool better.
The only problem is that most expansion valves are located beneath the dash and are hard to get to. The evaporator core and condensor core need to be flushed out also. I can't remember the brand, but there is a chemical flush made for a/c systems. If there is a dark, goopy film built up inside of the high-side lines and condensor, the carburetor spray cleaner works good at removing the residue. The condensor core can be flushed out by injecting the chemical into the inlet side and blow it through w/compressed air. I blow it into a shop towel and see if any particles come out in the flush. If there is crap in the system, then keep flushing until it comes out clean. Don't breathe the fumes (or mist), you might want to use a painter's respirator. I have a big fan I use to ventilate the area too. Keep the stuff off the paint, or you'll be paying your body shop a visit.
I use a freon called "Freeze-12" that works excellent in R-12 systems. I run it through my #12 gauges so there is no need to use the adapter fittings. With the Freeze-12 freon, I use the 134-A P.A.G. synthetic oil--do not use the oil recogmended for R-12--. If it is a 134-A system, then I use 134-A freon. Since R-12 systems have a less-efficient condensor core, 134-A will not work. The Freeze-12 seems to work as good as R-12.
One more thing, if there is a lot of crap in the system, then a new condensor core might be a good idea, and always use a new drier.
Hope this is what you needed.
---TEX---
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