madfie

OK folks got my new engine in and running great. Now for the a/c. I'm sure it's low on r12 but before I put in my 20 dollar a can r12 I want to test if the clutch is good. Do I send 12 volts directly to the white connector on the compressor or jump the low pressure switch. I used a test light and went from battery to the white connector on the compressor with no clutch lock-up. Should I do the low pressure switch and if so is it behind the glove box or by the drier. Sorry 1986 4runner 22re. Thanks in advance.

millball

You can jump the clutch connector wire to the battery + terminal to test it.

There is high resistance thru the test light that would not permit sufficient current to pass to energise the clutch.

The test light did light up did'nt it??

grumpin

I jumpered the low pressure switch to check mine.

scope103

That R12 isn't just mysteriously disappearing, it's leaking into the atmosphere and wrecking the ozone layer. You can keep slowly killing us all, or spend only a little more and fix it. https://www.yotatech.com/forums/f116...-r134a-284801/ (It was "easier" for me because I replaced the compressor.)

Or at least do it half-way; get some UV dye in the system and FIND the leak. Then fix it, and the $60 of R12 (sounds pretty cheap to me; you gotta connection?) to recharge will be the last time in a long time.

bswarm

I hope it's not the phony R12 that was going around a few years ago that had propane in it. Why not convert to R134a?

scope103

Other than the fact that you're getting ripped off if you think you're buying R12, is there really a problem with propane? I think this stuff is mostly propane: http://www.es-refrigerants.com/produ...-kit&Trying=ON It's probably illegal to use for a complete recharge, and there is the issue that you've got flammable gas in the cab, but if you're leaking R12/R134a into the cab that can't be doing you any good either.

bswarm

One of the first things we had to do when servicing A/C in the shop was put a freon tester on the car. It identified the type of freon and if it was contaminated or not. There were a few that were contaminated, and hooking them up to recovery equipment was a no-no, it would have contaminated the entire batch of refrigerant, which was 50lbs each tank, and all the filters and driers in the machine. We were told to simply turn the customer away.
Some trivia... I remember when K-mart sold R12 for 24 cents per lb.

madfie

I bought the runner and rebuilt the engine. I have never used the a/c so I figured it is empty. My vaccuum and guages just came in and I got o rings and drier. I'm going to re do all of it I just would like to know if my clutch is working so I can do that too. I wouldn't put the r12 in before I checked for leaks. But it would suck to put it in then the clutch didn't work. Anyway you want to live forever. I know there is worse things in the air than r12. Lol By the way I live in vegas and found 5 cans of dupont for 100. Found another guy in lake havasu that has 2 cases of sercon also for 20 a can if you buy five or more. Thanks for the info on low pressure switch. I'll look in my Fsm to locate it and try that on tues

millball

I don't know what the latest military protocols are, but I know that they used to use various chloro-fluro-carbons (freons) and tricloroethane type solvents by the thousands of gallons to clean and degrease aircraft parts, with no regard to the emissions. They likely still do. They have always had legal exemptions that ordinary citizens are not permitted.

Most of the rest of the world, outside of the USA, is still awash in virgin R-12, regardless of the international agreements.

Even here in the US where we rely mostly on stashes of old production goods, The price is coming down, because there is more product still available than machines that still use it.

Now they are getting ready to eliminate the use of the second gen refrigerants in order to advance to god knows what.

Many of the hydrocarbon based refrigerants are very good, if you can overlook the flamability issues.

madfie

Ahh southern az. Grew up in Tucson and moved to another desert. Lol. Ya I work for the FD here in Vegas so I get to play in all that stuff. LOL. Been reading a lot on the computer duster r152a. Might have to stock up on that.

madfie

Thanks for the help. I jumped my low pressure switch and the clutch engaged. I pulled vacuum but could only get it to -22 or -23. FSM says 27 but I hear that differs with temp and altitude. But it did hold for over an hour. I'll replace all o rings just for good measure. The system had nothing in it so it had to go somewhere.