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truk4u
01-15-2009, 10:13 PM
I know, I'm boring you to death with this A/C stuff, but hopefully some will find it informative and maybe save them some money and aggravation.

I'm getting ready for a compressor change and the oil becomes an issue if your still using R-12. The new CCI/York compressor's (mine was manufactured 6/08) comes filled with PAG oil. Earlier ones and maybe other brands use Ester oil. CCI/York insists the oil has to be changed out to Refrigeration Mineral Oil when using R-12. I got the Mineral Oil at NAPA for 4 bucks.

I didn't even know the compressors had an oil sump that holds 14 oz of oil and plugs for checking the oil. They even make a dipstick to make the oil check easier. To further blow your mind, some even suggest changing oil at some interval as a maintenance item.

So here's what the compressor looks like on the bench:

3968
Compressor with plug removed
3969
Better shot of the plug (there's one on each side)
3970
PAG oil was removed and replacing with Mineral Oil
3971
Data plate shows Mfg. date, model, part number and oil type.

I'm sure Jon has already changed his oil and has made his own dipstick.:p

Jimmy C - Don't harass me about the camera date, I keep changing it and it keeps doing it's own thing and it's the King's fault!:mad:

lewpopp
01-15-2009, 11:04 PM
Truk,

I hope you figure out the compressor bit with the 91, where to get one at a good price, how to easily change from R-12 etc. I have a compressor I've taken the belt off of months or years ago that needs replacingwhen the time comes that you have ironed out all of the rough stuff.

Jon Wehrenberg
01-16-2009, 06:36 AM
Hey sheepherder, I happen to be one of many Liberty owners that doesn't fuss with stuff like that because I happen to have one of the real Liberty coaches with OTR.

How can you have a dipstick to check oil in a system that is supposed to be sealed. Draw pictures and talk slow. I can't get that one through my head.

truk4u
01-16-2009, 11:08 AM
Hey Dog Boy, I like the bay storage and don't need no stinking OTR.:rolleyes:

They refer to the bottom of the compressor as the crankcase and obviously it's a closed system separate from the top. Here is the manufacturers instructions in case you think I made all this up:

OIL CHARGE
If the quantity of oil is unknown, the compressor oil level
must be checked at the time of installation and again
after the system has been fully charged with refrigerant
and the system has been operated and balanced out to
the desired compartment interior temperature.

Now, be a nice Pogger and offer to lend out your dipstick (the one for oil, not the one that needs tweezers).;)

Jon Wehrenberg
01-16-2009, 02:28 PM
OK, I know you understand mechanical things. That looks like a piston type compressor. How can the freon not leak past the piston or piston rings? Once it does that freon is in the crankcase and then leaking out whenever the dipstick is pulled.

Talk slower. I didn't get it the last time.