I have spent way too much money on my a/c since it has been converted to to 134a junk. Where I live it does not cool acceptably! Why doesn't the 134a cool like the old r-12?
Aside from converting back to the r-12 what can I do to get this truck to cool like it did from the factory? I've been thinking.....could one add another condensor?

Thanks, Tony

 

use propane.cheap, cold

 

Ok I'm game.....I'm probably gonna need a little education....can u help or wanna PM me?

Thanks

 

My 91.5 was converted to 134 a year after I got it because the AC didn't work. Too hot in AZ for me without it. Never had a problem with it. When mine was done, they put in a new compressor (as mine was the cause of the leak) and new lines. If you are having a problem, then someone didn't do it right an/or you have a bad component.

 

I converted mine to 135A and it blows icicles. See here . If it wasn't converted right, with the proper amount of 134A, it loses cooling. Also check you ac/heater plenum box, mine was full of pine needles. As Jim Lane said in a thread, 134A likes air flow and if the plenum is full, it won't cool well...Mark

 

Mayb368, do you have an icicle temp reading? The reason I ask.... with r-12 idling the temp would be 39* now it never gets below 49* That's not cool enough for me.

Thanks folks for the help!

 

Yeah, I get into the high 30s. It is very possible that you are over charged. Does your system still have a sight glass? If it is clear, or nearly clear, it is over charged. Try putting in the thermometer and take out a little 134A and see if the temp goes down. Also, like I said before, your ac/heater plenum may be full of stuff from the cowl. On the last page of my AC thread there is a link to photos of how full mine was...Mark

 

I use a mixture of 71% propane to 29% isobutane. Works out to an 8 oz can of mountain stove fuel and 14 oz of propane. I use ISO-Heat and Coleman for quality.

Cools like R-12, but doesn't leak off as readily. It's about half the molecular weight of freon, so it takes about half as much to charge.

Most automotive systems take about 20 - 22 oz of this mix to work right, so you can dump in the can of stove fuel, then follow it up with propane till the pressures are right. (R12 scale)

for a bigger system, like a conversion van with a rear cooler in it, I mix up a couple cans of each in an old R12 refrigerant can with a decent valve welded to it. (evacuated first of course)

Don't use bulk propane. It's too wet.

I've fixed several systems from 1960 Cadillac to a Caravan van with this stuff. You could hang meat in em.

 

have you tried pulling the temp control probe out of the suction line to reduce temp and increase compressor cycle time?

 

There's reasons for that control, one of which is to prevent liquid in the suction side of the compressor, which will damage it.

 

So you open the system to pour in the mountain stove fuel? How do you go about connecting the propane to the gauge set?

 

I don't think he means pull it completely out, just partially...Mark

 

I am still running R12 in my system with the sight glass not clear and getting 40F.
Should add a little freon from the 50lb cylinder I was given when I retired.

 

Actually the mountain stove fuel is liquified petroleum, 80/20 isobutane/propane. I found with a little Dremel tool work, a top piercing tap for the old R-12 cans will work. I just put a ball valve and a 5/16 (I think) flare fitting on a 1" propane can adapter for the Coleman propane.

I've been looking for a proper adapter to the mountain stove fuel cans for some time. Can't seem to find one.

 

No, don't use it. I'll come pick up that scrap and properly dispose of it for you.

Actually, if it were mine, I'd sell it on the open market, charge my system with propane, and buy a truck with the remainder.