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Old 06-23-2013, 01:18 PM   #1
1slo_camaro
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A/C in my 78

my truck came stock with A/C and i honestly plan on keeping it that way. my only concern is the PO said the A/C worked perfectly fine until it needed to be re-charged and they asked a shop and they wanted a good chunk of change to do the job since it is R-12....

should i buy R-12 (myself, father, and grandfather all are ASE Certed to buy R-12)

or buy a retro kit and throw in some R-134


my ase cert is from high school so probably lapsed but with these retro kits is it just drain the system, and fill with r-134? they just have the caps that go over your R-12 line connectors right? and I would need to add PAC Oil right?


can anyone help me? i was spoiled with my Jeep with AMAZING A/C through the summer and idk if shes gonna hit the road and i wanna cruise my truck down to the beach but can not stand not having ac anymore lol
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Old 06-23-2013, 01:50 PM   #2
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Re: A/C in my 78

Unless you plan to change the condensor for R134, refill with R12. Besides a new condensor, you'll need new hoses too. R134 will leach out R12 hoses. R134 is a smaller molecule. R134 hoses have a plastic barrier between inner and outter sidewalls. Fix the leak and recharge. I had a compressor checked for compression and new seals for only $98. Good insurance against failure.
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Old 06-23-2013, 01:56 PM   #3
1slo_camaro
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Re: A/C in my 78

damnit.... figures. nothing is going to be freaking easy!
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Old 06-23-2013, 02:29 PM   #4
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Re: A/C in my 78

I see no reason to convert if you, or someone you know can get you R12.
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Old 06-23-2013, 02:34 PM   #5
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Re: A/C in my 78

You live in a cooler climate. You may get away with using the R12 condensor. For warm and hot states, replacing the condensor for efficiency is a must.
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Old 06-23-2013, 04:03 PM   #6
1slo_camaro
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Re: A/C in my 78

Zane because the cost of it is pretty damn pricey.

and im not looking to use it everyday, just on longer trips down to the beach or whatever. so im just trying to do the bare minimum to keep the cab cool and the wifey happy.


obviously i am taking for granted that the PO didnt lie and the system is all intact and wont leak or anything or the compressor isnt wasted so fingers crossed. im thinking of picking up a autozone special of the 134 retrofit kit for like 60 bucks.... anybody have any experience with that?
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Old 06-23-2013, 05:48 PM   #7
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Re: A/C in my 78

For best results with the R134A conversion you want to flush out the old oil, replace the accumulator/drier, fix any leak, put the right amount of R134A oil into the system and charge with the 'correct' amount of R134a by weight (about 90% of the R12 amount). Will likely have to adjust the cycling switch on the accumulator also.

Anything less and you're likely going to have reliability problems and lack luster cooling.

I've read that our stock condensers work pretty well for R134A use.

(I have yet to do all the above on our 86' but will before summer is over).
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Old 06-23-2013, 06:06 PM   #8
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Re: A/C in my 78

fingers crossed i dont have any leaks. i have oil and all so that i feel pretty good about. and i have gauges and a HVAC guy that is pretty damn knowledgable about all this HVAC stuff and between myself my old man and grandfather and the forum pages im sure we can figure it out to blow cold! lol

i appreciate the advice guys. hopefully im posting soon about the ice cold air blowing out my ducts
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Old 06-23-2013, 06:20 PM   #9
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Re: A/C in my 78

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Originally Posted by 1slo_camaro View Post
fingers crossed i dont have any leaks. i have oil and all so that i feel pretty good about. and i have gauges and a HVAC guy that is pretty damn knowledgable about all this HVAC stuff and between myself my old man and grandfather and the forum pages im sure we can figure it out to blow cold! lol

i appreciate the advice guys. hopefully im posting soon about the ice cold air blowing out my ducts
Very interested in hearing the outcome!

Here's my thread on our 86 (getting ready for it anyways) over at Aircondition.com. Nacho over there is very knowledgeable about many different vehicles and conversions.
http://acsource.net/acforum/viewtopic.php?f=1&t=10198
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Old 06-23-2013, 06:33 PM   #10
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Re: A/C in my 78

sweet, im going to try the lazy cheap route with fingers crossed and get the kit and vaccuum the lines out and fill them up with 134 and the compressor with oil and see how she works, hopefully i can get a pic with before and after with a thermometer, but my vents only blow on defrost and the floor..... i havent ventured into that problem yet
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Old 06-23-2013, 10:26 PM   #11
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Re: A/C in my 78

I was in the same boat with my 84 gmc classic. I had r12 and when we did the motor swap it all leaked out so I thought about keeping the R12 because everybody says it blows colder and it might but I wanted to be able to recharge it my self and I am not certified to do it and r12 is very expensive. So I took it to a local shop and he shot me 2 prices. 1st was to do what they called a Dirty Retro and if my compressor, condenser,dryer and orifice tube where all ok they would vacuum all the old out flush it and add a new fitting, oil and r134 and be done for $300. 2nd was what they called a full Retro where they would replace everything Compressor, Lines, Dryer, Condenser, orifice Tube and Fill it for $1000. So I said go with #1...well they called the next day and said the Compressor had metal shavings in it and asked what I wanted to do so I called autozone ordered a New Compressor, Dryer and Orifice Tube for $220 total and had it the next day so at least if I am gonna pay for New stuff I am gonna make damn sure Its new not re-maned. Took it to them and said here ya go. So they flushed the system Installed all the new stuff I brought them...refilled it with oil and R134 never changed the lines or the condenser they charged me $330 and I have had it for about 2 years now and It blows 42 deg out of the center vent at idle and it was 94 deg here today. Seems ok to me. I am going to put a Mark Viii fan on it as soon as my controller from DCcontrollers gets here it currently has a stock clutch fan on it and still never gets over 200 deg in traffic. Its up to you I just like the idea of When I have to recharged it and You will sooner or later I can run to Autozone or Wal-Mart and Grab some R134 and charge it when I have too. Good Luck

Last edited by nosfed2; 06-23-2013 at 10:32 PM.
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Old 06-24-2013, 01:11 AM   #12
andrewmp6
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Re: A/C in my 78

Look on craigslist i have found r12 cans cheap before on there.
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Old 06-24-2013, 03:05 PM   #13
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Re: A/C in my 78

If your truck started as R12, a previous owner put R134 in but did not convert the whole system, can you go back to R12 and is it worth it?
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Old 06-24-2013, 09:01 PM   #14
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Re: A/C in my 78

Quote:
Originally Posted by 1slo_camaro View Post
but my vents only blow on defrost and the floor..... i havent ventured into that problem yet
check here,see if this clip is broke
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Old 06-24-2013, 09:33 PM   #15
1slo_camaro
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Re: A/C in my 78

andrew i have a HVAC cert guy with everything oil and r134 by the large tanks like 50lbs lol so im good there and is only gonna cost my like 40 bucks fingers crossed the system holds vaccuum thats what im going to try exactly what you did.

Also im going to be throwing a jeep grand cherokee elect fan in it and leave it on a switch ( i did that on my camaro and its nice on hot days i can turn the car off and leave the fan on for a little) or get fancy and get a temp triggered switch. kinda like a turbo timer for my fan hahaha

motornut- thanks dude as soon as i get home i will have to check that out will i have to remove my dash for that? i know its a dumb question i just havent been under/behind a dash of these ol girls in a while so i forget what it all looks like back there
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Old 06-24-2013, 10:13 PM   #16
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Re: A/C in my 78

look up under the glove box area
It's behind the bulging tube off the front of the box
somebody here made the fix out of piece of metal
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Old 06-25-2013, 10:05 AM   #17
1slo_camaro
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Re: A/C in my 78

thanks, ill check when i get back home. kinda in the middle of the ocean right now haha
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Old 06-25-2013, 10:13 AM   #18
88Jimmy4x4
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Re: A/C in my 78

I replaced all parts on my 76 myself and used R12, mine gets down to 36-38 deg and holds it with fan on max and low speed and thats at 4pm hottest part of day 112 with heat index in Houston.
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Old 07-01-2013, 03:24 PM   #19
1slo_camaro
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Re: A/C in my 78

welp attached the gauges and she had some pressure so we filled it with some hot shot (r-12 replacement) and blows extremely cold. im going to need a compressor soon, so if anyone knows of a good used one that would be awesome! if not ill just wait and hope it holds out til this winter
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