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R134 Conversion

BIGSLVRXJ

NAXJA Forum User
Location
Des Moines, Iowa
I need someone who is an expert on A/C systems to help me here. I'm going to convert my 90's R12 to R134 by myself and need to know some info. I'm going to take it someplace to get it completely flushed and after that I have to replace my compressor,receiver drier, and expansion valve.
1. Does the condenser need to be replaced as well or will the system flush work for getting the R12 and all oil out?
2. Also my Haynes repair manual says to pour the oil out of the Schrader Valve of the receiver drier into a measuring cup.
3. Is there anything else I need to do?

Thanks in advance
Collin
 
FWIW, i recently replaced most of the A/C on a ZJ, and the new compressor contained the correct amount of oil for the whole system. I think the reason you're supposed to measure the oil in the receiver/drier is to estimate how much oil you need to add once everything's been installed.

as far as the condensor (and evaporator, while we're at it), hopefully all the old oil is removed during the flush, since the oil used with R12 is not compatible with the R134a oil and can gum up your new compressor :eek: make sure the shop doing the flushing knows you're doing a conversion- maybe they'll be more careful about removing all the old oil.

i'm not an expert by any means, but I do have some recent hands-on experience with A/C :D

edit: just remembered- on parts you're keeping (condensor, evaporator, hoses), you might want to have the shop verify that they're R134a compatible. seems to me like the newer hoses have 'R134a' printed on them. also any old o-rings should be replaced with newer, compatible (green) o-rings.
 
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Go to an auto parts and buy the R134 retrofit kit ,about 35 bucks.Thats all you need. I've done it on aleast 20 vehicles no problems never replaced anything ,I know people who run like this for years with out a glitch.
 
Hackedxj the reason he's doing this now is because he did precisely that a year ago and it has destroyed his compressor because all the r-12 wasn't removed. Now the thing is about to blow and should be replaced before it does and throws a belt or worse.
 
Yeah Blair knows the story. I feel dumber than dumb having done this now but its time for a system replace.
 
Has your compressor ever been replaced? Maybe it was just its time. Don't want to steer you in the wrong direction . I am just saying I've never had a problem with it. I see vehicles I retrofitted in the mid 90's still working fine. Since your compressor is coming apart,I would agree with the flush to remove metal shavings.What makes you think it's the 134?
 
Ill do the best I can at explaining this. I put r134 in on top of the r12 without evacuating it. My compressor already had a bad bearing before, I believe, but now it is incredibly loud and shakes my floorboard. Its a fun noise and feeling, trust me.
 
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