My A/C blew warm & warmer until finally it never got cold. A/C tech told me it has a leak. I just heard recently that you can put stop leak in the A/C system. I've never seen stop leak for A/C. Will this work? I only need this fix to work for the summer. So quick/cheap fix is what I'm looking for. I already bought a used compressor but keeping my already installed old one would be easiest. Can I retrofit for R134, put in stop leak & R134 freon & be on my way?

Believe it or not, I have drove without A/C in MD summers for 2 years now! Talk about a quick weight loss program...

I would go to the local auto parts store and get some "freeze 12" or some other R12 substitute with leak stop or whatever. Most of those things come in cans ready to screw onto the low pressure adapter.

Make sure whatever it is doesn't make it impossible to switch to R134a later.

If it were me, I would leave out the leak stop and just go for a quick charge if the leak is a slow one.

BTW, R134a is going up in price very rapidly. It used to be less than $4 per can at Walmart, as of last night it was $7.88 per can. Those are 12oz cans. I am hearing of local shops charging $60 per pound (16oz) because the price has gone up so much for them. Walmart's R134a price rises much more slowly because they buy in such hich quantities that the price increases hit long before they run low and have to buy again.

Clay

You're leaving out an important piece of the puzzle. Where (specifically) is the leak?

what year did they go to 134a i have 94 and it came with 134 in it
did u guys see my post about the AC fan. not as cold during the day but freezin at hiway or night driving. y is that. do i need a recharge

Thanks for the info Clay. Curious why you would leave out the stop leak. Maybe try just a can of R12 first & if it leaks then try the stop leak? Where have you seen the R12 substitute?

The tech just said "it's leaking out". I think he used a sniffer. It was a free A/C checkup so he wasn't gonna put anymore time than necessary. It was also over 2 years ago so the memory is kinda hazy on this.

What do you think about the R12 substitue or the A/C stop leak?

R12 substitute is available at most auto parts stores and Wal-Mart.

I wouldn't use stop leak because I don't know what's in it and if it can cause problems down the road. If it takes 2 years for the freon to leak out to the point that you need a recharge I wouldn't start throwing money at it until I absolutely have to. I'm just cheap is all.

R12 substitutes are fine, but you might have to, um... arrange for an accidental discharge before you take it in for a/c work. Some shops see the substitutes as contaminated freon.

Clay

Charlie, regarding the leak itself: you can buy a cheap can of this stuff (forget what its called), but it glows under a black light. Its specifically for finding leaks in AC.

you just attach it like a refill can and it enters the system.

You then just pick up a black light bulb for a buck or two and use it to find the leak. Turn on the AC and shine the light in the engine bay, or if that fails, under the passenger side dash. Obviously a darkened garage, or evening outside works best.

If its in a spot that you can get to, it can easily be patched with a dab of high pressure-rated epoxy.

Didn't realize there was such a thing as R12 substitute. Thot you had to replace with R12 or retrofit. Anyways, I am going the substitute route. Only need it for this summer. Hopefully the leak isn't so bad that it leaks out fast. Geeez, compressor hasn't been run for a couple of years. Hope it's not froze...I took the belt off when I couldn't use A/C.

Here's a list of EPA approved R12 subs: R12 substitute article
Scroll down to the bottom...

Guy, thanks for that. I will go that route to see if the leak is an easy fix.

It's dye. I use it every day. It works very well as long as the leak is large enough to lose oil. The dye gets mixed with the oil and doesn't really mix with the refrigerant itself.

I use an LED blacklight flashlight and a pair of yellow safety glasses to find it. Cool stuff.

Clay