Speaking of ac... gotta question

[SBpunk]

So pulled a junkyard AC unit from a 92 Cherokee. Seems like its in good shape but was hoping for some input. I decided to go rogue and tried to add R12 to my old ac compressor and everything started locking up. This time I'm going to get it done by someone who knows what they're doing. Its been sitting in the back of my WJ for about 3 months so  besides putting new oil in and having it vacuumed (not sure if that's the right phrase) out anything else I should check for?

[Marine1Texas]

Yep vacuum down, change dryer receiver, add oil for the Freon your using. then your be set for many years

[1989 comanche mj]

Whatever compressor you are gonna use turn it upside down, put clean oil correct for the system in, then grab the clutch and spin it over until all the oil comes out clean.  Repeat until clean oil comes out.  You want to flush it out.  Then put the correct oil in it and bolt it in right away and run vaccuum for 45 minutes.

 

I never put r12 in a questionable system, its too expensive.  Put in 134 or a cheap r12 substitute and see it it holds and works for a week, then switch over.

 

On my 92 I just went with all 96 xj parts from the firewall out, its factory 134.  R12 hoses will leak 134 right through the rubber.  Not a lot but enough to need to top off yearly.

[Tex06]

Do you have gauges?  Those help too. I have everything to convert mine from rockauto, ran me about $400 for new lines and a 134a compressor.  Do we have an orifice to pull like the chevy's of the 80s?

[Newton]

I put maxi- frig r12a refridgerant in my stock r12 system..i got off eBay its both r12/134a compatible been almost a year now no problems..

$80 for 2 cans of refridgerant 1 oil charge and one leak stop which I wouldn't advise to use plus charge hose with gauge

[SBpunk]

I've got 9 or so cans of r12 I found in the attic of our house when we bought it. Was more concerned with the compressor. I do need to grab a new dryer though. Not trying to convert to 134 anytime soon. R12 works like a champ still and it's free so might as well use it. I'm going to talk to a buddy about putting it in after I clean and hook everything up. He's an hvac guy so should know what's up.

[1989 comanche mj]

No orifice to yank like on a chevy.  The ac systems on our trucks works fine converted to 134.  Its the same system that cools down an entire cherokee.  I would sell the r12 cans, with the cash you could buy 30lbs of 134 and a gauge set.  But if you insist on using the 12 bring a propane torch and heat the cans while charging to get every last bit out.

 

I'm not a fan of the frig 12, its just propane and a little isobutane or similiar, but way expensive.  It does work real good though.  Super flammable.  Cruising along smoking and the evaporator springs a leak could be an issue.  But I would use it in my old chevys which just don't get cold with 134 no matter what you do.   You could charge with propane first to make sure the system is working before putting r12 in.  You have to make sure the junkyard compressor works.