Trying to figure out how to recharge my A/C system

fatwagn72

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the a/c on my 1972 dodge will blow air, its just not cold, the compressor works and everything, and i think its just a matter of recharging it. i know that i can easily recharge it with some a/c pro or something, but on the recharge guide and videos, it says to find the low pressure a/c service port. i am having trouble figuring out where it is.

thanks

p.s. is a/c pro the best way to recharge my a/c?
 
First things, first. Are you still running r12 or has someone converted it to 134?
 
ACrepair02.JPG

I don't know how different the plumbing is on your car, but here's the RV2 compressor on my '65. The blue hose is the low pressure side. The red hose is the high pressure side.

I hope this helps.

-Carl
 
so i think it is still r12
If it was changed, the port fitting will have an adapter for the 134. R12 can be a bit hard to come by, and pricey $$. I had an hvac guy give me a full jug of it, that's your first hurdle.
 
First car with A/C?
I suggest you bring it to one of those shops that have a big sandwich board out front that says, A/C SPECIAL $59.95. It will come to more than that but it beats buying $15 cans of refrigerant and not knowing what you're doing.

I'm all for DIY and learning from it but not in this case. Yet.
 
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If it's plumbed the way my '69 NY is, the line going FROM your compressor to your condenser (the finned, aluminum part that sits in front of the radiator) will be the high pressure line. The one going TO your compressor from the evaporator (which is inside the car, beneath the dash) will be the low pressure line. You will find 3 Schrader valves in the area of the compressor. Two close to the front and back of the compressor, and one on the head of it, all beneath brass screw caps. In this photo, you will see the new fittings on my converted system. The one more prominent in the photo is where the high side port is, and the one behind the compressor is for the low side. Having said all this, I believe you should do LOTS of homework on exactly how your system is set up. Stan's idea is not a bad one if you're not terribly familiar with these systems. If you do decide to DIY, be careful, deliberate, and do exhaustive research.

13497700_1211681772184066_3846613483423495699_o.jpg
 
You can see the fittings in celticwarloc's pic that are retrofit fittings for R-134A, if you don't have something similar than you probably still have R-12. You DON'T want to mix the 2 refrigerants. If you don't know for sure as was suggested above head for a A/C shop
 
Like Stan says. Best leave it to a pro.
There's more to it then just squirting Freon into a non working system. It will require a vacuum pump to dry out the system and verify it will hold pressure. (12-15 inches of vacuum) for a half hour or so and it should be a tight system.
And R-12 ain't cheap.
Your system can be converted to use R134 by changing the rubber pressure hoses and all the seals. Should replace the receiver dryer also.
Vintage air can supply everything you need.
 
DSC03126.JPG
The Admirals updated system...... Center dash vent temp is 30 degrees now. It still takes awile to cool down the interior of the wagon, a lot of glass there.
 
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Without getting into any debate on good/bad ways to do this, or mentioning R12 compatible refrigerants...

The larger line is always the low, suction, gas, side. The smaller line is the high, pressure, liquid side.
 
Any hiccups during the installation?

Pretty straight forward. Everything needed, (except the belts, which only took 5-6 trips to the parts store to get right), came with the kit. The compressor conversion brackets don't allow for exact belt alignment and without completely redesigning them I don't see a way to correct it. Just a minor issue.
The only part I did not replace was the condenser. And it leaked. I pulled one from a 69 Fury my friend in Tenn had, pressure tested OK and is working fine in the Admiral.
 
Wait....
The compressor conversion brackets don't allow for exact belt alignment and without completely redesigning them I don't see a way to correct it. Just a minor issue.
I don't call that a "minor" issue. So the brackets are **** then...

Everything needed, (except the belts, which only took 5-6 trips to the parts store to get right)
Of course...

The only part I did not replace was the condenser. And it leaked. I pulled one from a 69 Fury my friend in Tenn had,
Now your confusing me.
1. When you got the car, whst kind of compressor was in it.?
 
Wait....

I don't call that a "minor" issue. So the brackets are **** then...
Lets just say the brackets are functional. The misalignment is hardly noticeable and the belt stays true in the groove.

Now your confusing me.
1. When you got the car, what kind of compressor was in it.?
There was NO compressor. The original V twin compressor had been removed. I acquired a correct single groove that turned smoothly but was untested, but decided to upgrade to the Sanden type. It's smooth and quiet and RPM drop when engaged is hardly noticeable.
 
the a/c on my 1972 dodge will blow air, its just not cold, the compressor works and everything, and i think its just a matter of recharging it. i know that i can easily recharge it with some a/c pro or something, but on the recharge guide and videos, it says to find the low pressure a/c service port. i am having trouble figuring out where it is.

thanks

p.s. is a/c pro the best way to recharge my a/c?

Sorry this is late... Because you asked about "A/C PRO"... I believe your best option is to to just pay a professional to handle this. A year or so ago while waiting my turn at the counter at the local AAP I amused myself walking around the store checking the half dozen endcaps loaded with refrigerant... not one can without sealant. Anybody who uses sealant shouldn't touch your A/C and the DIY stuff all seems to have it. I bought a 30lb cylinder for economics, but if I wanted a smaller quantity, I would make darn certain there was no sealant involved.

If you don't own the proper equipment to vacuum the system (assuming it's fully discharged or recovered elsewhere), the moisture in the system will activate the sealant and basically ruin the entire system. There are flush agents that can remove non-activated sealants, but once hardened... game over.

BTW, most shops don't want your sealant in their equipment. If they detect sealant in the system you just went from "free A/C check" to very expensive repairs.
 
There was NO compressor. The original V twin compressor had been removed. I acquired a correct single groove that turned smoothly but was untested, but decided to upgrade to the Sanden type. It's smooth and quiet and RPM drop when engaged is hardly noticeable.
Thanks. I'm getting this sorted out now.
So.......
You bought a Sanden type and supposedly "correct" conversion brackets for the Sanden type BUT the conversion brackets did NOT allow for an exact alignment.
Correct?
 
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