Need to recharge an R12 system. Should I replace....

I need to recharge my R12 system on my 77 Electra.
I'm pretty sure it needs recharging. It was working well, then short cycling, then quit all together. My questions are:
Should I replace the orifice tube and drier?
Should I have it evacuated, and checked for leaks?
Should I look for a variable orifice tube, if I replace it?
Should I just add some R12 and leave the system closed.
What about an inline filter????

Thanks, and stay cool! :bglasses:

ElectraJim

 

How about fix the leak, pump it down, and recharge?

 

Yes, I could do _just_ that at a minimum, but I was wondering if there was any "while your at it's", I should do, for best cooling, and long life.

ElectraJim

 

Topped off with 2 cans of R12. Blows air in the 40's now.

ElectraJim

 

Butttt how long will it last?

 

Everyone one adds freon when low but NEVER think about adding the lost oil that was also lost when freon leaked out. That's one reason A/C systems have catastrophic compressor failure. NO OIL!!!!! Add a few ozs. of oil now before the system self destructs.

 

I disagree. I work on A/Cs for a (college) living and a full system leakdown will only lose enough oil to cause a stain. Not even enough to measure.

 

home & vehicle A/C's are different animals.

 

The real problem with automotive AC is that the oil migrates from the compressor and collects at the low points throughout the system. I have a chart somewhere around here that tells how much oil to put in the system (R-12, don't know if it applies for TC-134A or these other new refrigerants but don't see why not) when changing out parts.

 

In ways, yes. However, the same basic refrigeration principles and characteristics of Freon hold true.

The real problem with automotive AC is that the oil migrates from the compressor and collects at the low points throughout the system. I have a chart somewhere around here that tells how much oil to put in the system (R-12, don't know if it applies for TC-134A or these other new refrigerants but don't see why not) when changing out parts.

That's some good information.

 

Ok, I'll check the oil....Now where's that AC system dipstick.... p
Well, checking, changing, or adding oil to the system was one of those "while you are at it things" but it wasn't mentioned.
Fortunately, one of those cans of R12 that I added has "blue dye" in it to check for leaks. I haven't seen any leaks yet, and I don't have visual evidence of oil leakage from the AC system anywhere, not even out of the front of the compressor.

ElectraJim