euclid
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Anyone seen a thorough thread on AC conversion specific to 1985 +/- 4-runner? Mine is R-22, not keeping up with 95 degrees and 90% humidity.
AC conversion thread (1 Viewer)
- Thread starter euclid
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How to install A/C in a 1st Gen Pickup/4Runner
UPDATE 4/4/24 - For more pics/info on drilling the holes for the evaporator & installing the compressor bracket, go to page 4 of this thread Here it is! The much anticipated writeup of how to install AC into a 1st generation 4Runner or pickup. I’m going to warn that this is going to be a very...
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R-22? How about R-12?
I can tell you that converting from R12 to R134a was not what I expected. I had heard that R134a does not cool as well. I will agree and confirm.
I used to live in Palm Springs and my R12 system had no problem keeping cool.
I can tell you that converting from R12 to R134a was not what I expected. I had heard that R134a does not cool as well. I will agree and confirm.
I used to live in Palm Springs and my R12 system had no problem keeping cool.
I just converted my 1990 runner to R134. It was not complex. Here at 108* in vegas I am not disappointed with the way 134 works at all. I have not done a actual temp of the air coming out of the vents. But good lord it helps. See my project creampuff for the Toyota TSA on the conversion. I would not get toyota parts honestly. Rock auto has everything you need and it's cheaper.
Coming from an HVAC tech, I’ll tell you that R12 is a far superior refrigerant. It is way more efficient in its lower boiling point which allows is to turn from liquid to gas faster allowing better heat transfer, AKA colder air. It also allows the compressor to not have to work as hard, prolonging compressor life. In addition to all of this, R12 is a lower pressure refrigerant which is easier on the entire system and less prone to leaks. Miss you R12, too bad you killed our ozone.
It may be because my system is completely new but my A/C is doing extremely well here in Tucson with R134a - and it has been averaging 106-111 degrees here lately. Before I converted it to R134a I would clean out the whole A/C system and replace the drier and expansion valve at the very least. I would do a good inspection of the compressor and make sure it still has plenty of compression.
I had to replace my evaporator.
euclid
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- #10
I've got a new drier and expansion valve are on the way. O-Ring kit as well. Plan to clean the evap up while I'm in there for the expansion valve, replace the o-rings that are accessible, flush the system, pull a vacuum then recharge the system. If it won't cool well enough then I'll circle back around to a compressor rebuild.
Just an FYI. A NEW Denso is $220 at Rockauto. I would do this instead of getting what you have rebuilt, or purchasing a junk rebuild. Oh, wait, it is what I did.
Hey Greg, good to hear from you again.
I rebuilt a compressor once, when it started leaking from the main seal behind the clutch. It was not easy, I had to get a special set of snap ring pliers, and the seal was really expensive. Got it all back together, charged up, working (converted to R134a), and a couple of months later it started leaking again. Ripped the whole thing out. We're tough up here in NH and don't need no steenking AC. Which was the cause of the thread posted above.
Be very careful removing the short line from the drier to the condenser part# 88716-89138, it only came on the 84-89 4runner and is no longer available
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I'm extremely happy with the quality of my rebuilt 4 Seasons A/C compressor I got from AutoZone. It has a lifetime warranty on it and seems to be holding up well. Like I said, the A/C is extremely cold in my rig here in Arizona.
Makes me wish I had harvested all the hard lines when we had trucks at the boneyard.
Suggestion. Don't use open end wrenches on those nuts. Use flare nut wrenches.
euclid
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- #16
My buddy thought he had a flush gun but couldn't find it so I'll get one tomorrow and try to wrap up the job.
Couple of followup questions.
I've already installed the expansion valve but I didn't flush the evaporator while it was out. Will it hurt the expansion valve to run flush through it, or should I take the assempbly back out and flush the evaporator independent of the new expansion valve?
Seems it's important to get the old R12 PAG out and replace with the new stuff. How have y'all cleaned the compressor in a swap from 12 to 134 in the past? Step D of the repair procedure in the TSB talks about replacing o-rings at the service valve plate. Will I be able to get most of the oil out while the compressor is off without rebuilding the compressor?
Couple of followup questions.
I've already installed the expansion valve but I didn't flush the evaporator while it was out. Will it hurt the expansion valve to run flush through it, or should I take the assempbly back out and flush the evaporator independent of the new expansion valve?
Seems it's important to get the old R12 PAG out and replace with the new stuff. How have y'all cleaned the compressor in a swap from 12 to 134 in the past? Step D of the repair procedure in the TSB talks about replacing o-rings at the service valve plate. Will I be able to get most of the oil out while the compressor is off without rebuilding the compressor?
R12 uses mineral oil. Originally, 134a used polyester but then in later years switched to PAG which is supposed to be compatible with either refrigerant. I’ve done 3 R134a changeovers and each time we just got as much oil out of the compressor as possible and filled it up with PAG. As long as you didn’t tank a compressor and launch debris in your system, just flush the evaporator with the txv in place in the proper direction ( small pipe in, big pipe out)
Don't just replace the O rings you can easily get to. Replace all of them.
My 60 and the runner both got converted to R134A. Drain the oil out of the compressor and fill away. 1/2 in the compressor and 1/2 in the Drier. Use PAG45 oil
My 60 and the runner both got converted to R134A. Drain the oil out of the compressor and fill away. 1/2 in the compressor and 1/2 in the Drier. Use PAG45 oil
euclid
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Got the compressor out and found oil leaking at the main seal behind the clutch where @KLF talked about.
Went ahead and drained it and put it back on. Got it re-assembled but it won't hold a vacuum. Replaced all o-rings except for on the condenser right behind the grill.
My ARB bumper is a little bent, making it impossible to remove the grill without taking the bumper off. Y'all think it's the compressor leaking or am I about to jump off into taking the bumper off to get to those last few seals like @Mace mentioned?
Gonna go ahead and order a rebuilt compressor from rock auto.
Went ahead and drained it and put it back on. Got it re-assembled but it won't hold a vacuum. Replaced all o-rings except for on the condenser right behind the grill.
My ARB bumper is a little bent, making it impossible to remove the grill without taking the bumper off. Y'all think it's the compressor leaking or am I about to jump off into taking the bumper off to get to those last few seals like @Mace mentioned?
Gonna go ahead and order a rebuilt compressor from rock auto.
you should buy a 94+(I think) 22re compressor as they were 134a. you may be able to swap heads for compressor hose connections
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