So I need to recharges my a/c after reassembling the dash. I have been searching and reading all the threads on r-12 vs r-134. First off I have no idea which type of freon or how much if any oil is left in the system before disassembly. There is no sticker but that doesn't mean it's not been converted. I have sawn a conversion kit on a free websites for a bj74. Should I just install these parts and take it to an A/C place to finish the job and run r-134? On that note does anyone know a reliable place to take a BJ74 in yhe San Diego, CA region?
BJ74 AIRCON. To convert or not to convert?
- Thread starter deepseacruiser
- Start date
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Take it to a reputable AC tech and let them decide the best plan.
Bj74 should fill up with R12 gas. R134 gas has bigger fitting on all round.
R12 while it still exist in limited amounts is getting harder and harder to find and will only become more scarce as time goes. My HJ75 is still running R12 simply because the A/C system has never had an issue therefore has never needed to be recharged. However my BJ74 system did have an issue and has been converted to 134A. Both products seem to to cool equally well.
Hope that helps....
Hope that helps....
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$0.02 worth
If all the components are functioning correctly, stick with the R12, it cools to a lower temperature and does it faster (nominally faster). But if your evaporator is gummed up or your expansion valve is sticky, then it might be reasonable to convert it. On a pair of FJ 62's my kids drive, one is original with R12, the other has been updated with a fresh evaporator and expansion valve with R134. The R134 truck cools better sitting in traffic, but the R12 does better at cruising speed, I think that's more a function of the good flow through the evaporator.
If all the components are functioning correctly, stick with the R12, it cools to a lower temperature and does it faster (nominally faster). But if your evaporator is gummed up or your expansion valve is sticky, then it might be reasonable to convert it. On a pair of FJ 62's my kids drive, one is original with R12, the other has been updated with a fresh evaporator and expansion valve with R134. The R134 truck cools better sitting in traffic, but the R12 does better at cruising speed, I think that's more a function of the good flow through the evaporator.
Chester and I are sorta saying the same thing.........
If it ain't broke ...... R12
If it is ..... R134A.
If it ain't broke ...... R12
If it is ..... R134A.
Chester and I are sorta saying the same thing.........
If it ain't broke ...... R12
If it is ..... R134A.
We coulda been brothers Charles, I've still got King George tags on my trucks.
Country, western, Strait or Jones, fully diversifried.
- Thread starter
- #10
Hey 1978hj45. Did you do the work yourself. Or take it somewhere?
Does any one know a reputable shop in Southern California?
I'm an un-talented dufus so no I didn't do the work. : )
I had a local A/C shop do the work and while I can't remember the exact cost, I don't recall it being unreasonable.
- Thread starter
- #12
I found a kit at euro parts 4x4 http://www.euro4x4parts.com/parts/ktr1000-2183_air_conditionning_gas_retrofit_kit.html. Since my lines are already empty and I dont know the condition of the system I will most likely replace these o-rings/seals and take to an A/C shop to evacuate all the old oil and refrigerant out and then charge with r134
- Thread starter
- #13
Also everyone says to replace the dryer with one compatible with r134. Does any one know of one that fits the BJ74 that is compatible or just replace with a new one that wasn't used with R-12
if it was used in the r-12 system it wont be compatible. if your putting new o-rings on put ac oil on them when you put them on and a bit of anti seize or grease on the threads. the shop will have to pressure test the system with nitrogen for leaks before they vac and gas it. dont be too surprised if some of the hoses need replacing, 134 is a smaller gas molecule than 12 so it can leak past the hose walls if they've degraded.