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How many cans / oz of r134a needed 2003 AWD

23K views 17 replies 12 participants last post by  AstroOafAdventurer 
#1 ·
Well after three years of weak compressor I broke down and ordered a kit on ebay. Side note, the one that failed was installed by the dealer under the extended warranty, it went weak a few days after the warranty ended and the dealer wouldn't honor it.

Anyway, harbor freight has 12oz cans on sale. With front and rear A/C how many cans should I get while they are darn near half price?
 
#10 ·
My 94 required a shot of juice a couple times during the summer, I started using this stuff called enviro-safe. Its only $6 a can and this stuff is ice cold. Its compatable w 134. Good stuff. Its from a place in Perkin, Ill. Not sure if its a local thing or if its available elsewhere.
 
#11 ·
zzimmer3 said:
I started using this stuff called enviro-safe.
Hey zzimmer3,
I researched enviro-safe earliest article I could find dates to 2001 so it's been around awhile. It is suppose to be 32% more efficient, requires less to recharge system, no need to pull a full vacuum and is a direct replacement. You said it's ice cold. How much of a difference in temperature compared to old refrigerant?
Anybody else on the site use the stuff? sure like to hear feedback.
 
#12 ·
Saved Big Money at Menards, R134A $5.00 or something per can, save your receipt get the 11% rebate later. $$$
Evacuate the entire system Check for Leaks, (THE COMPRESSOR IS USUALLY BAD), prior to charging. Don't waste materials. God Bless the United States of America.
 
#13 ·
My 1999 Safari SLE with Front and Rear AC took 4+/ 12 oz cans. Get a Fifth can for bleeding the lines.
Check my site for Compressor Rebuild tips. I've done Two rebuilds HT6. Both are working great.
Good times...
MattB.
 
#16 ·

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#17 ·
If you still have some charge in the system it's probably best to charge by pressure. I would turn on both front and rear A/C if running a test so both systems are operating. The question is, why did you need refrigerant in the first place? One can only hope a little leaked from around the compressor seal and you just needed a small top off. If you don't have gauges you can buy a refill can with a low side gauge on it. They aren't super accurate but they should put you in the ball park. Harbor Freight has a passable set for not a lot of $$.

They replaced R-12 with 134a. The temperature curves are similar, but don't try to mix/substitute them. Only 134a works. The alternative replacements often contain propane. Not really something you want to be adding to your A/C. A spark and a leak and we have fire. Why would anyone want to use anything else when R 134a is reasonably priced?

If a person wants to attempt a rebuild go for it. I would always opt for a replacement compressor to avoid future issues in an already PITA job. Who wants to be taking it out again in two weeks?

If you have a rather large leak I would begin with soap bubbles. If your ears are really good you might get lucky and hear a hissing noise.Aluminum piping and the rigors of the road are a bad combination, especially in an old vehicle. Once the leak is located and fixed, you have to vac it down through both front and rear systems. Technically I guess if you were sure you isolated one from the other this isn't a necessity. In commercial work we vac to less than 50 microns using a special gauge. Not sure on this as it applies to cars.If you had a good pump you could likely just let it vac for a long time to be sure. Valve off the gauges after the vac and wait to make sure. Then weigh it in by the specs.Hopefully this will be the end of your problems.

One thing I always liked about R 134a is the low side (suction) pressure- The blue line for those who don't know, is close to the coil temp on a pressure temperature chart. Only different by a few degrees. So if I have a suction pressure of 35psi with my system under a load, the coil is also close to this number in TEMPERATURE (F). We don't want a coil that low. A properly regulated system will be just high enough to avoid icing the coil up while still providing good cooling.If you have the proper charge and the system is under a load you should have a coil temp that is considerably above freezing. Probably not lower than 38F (coil temp) in a car. If it goes too low the condensation from the coil will ice up. The delta from inlet to outlet is healthy at 15/20F. If you have 85F in, you should have 70F out. As things cool down and you eventually get 74F in, you should get 55/58F out.
 
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