Red Angel. AC stop leak.

I've sold a few of them before. The customers never complained so I assume it worked.

It could be your leak is too big for Red Angel to seal.

If it leaked out in a day the leak is way bigger than stop leak can fix. Find someone with a refrigerant snuffer to see where the leak is.

Steve B.

When you have a large leak that sucks it down to zero PSI overnight or less, a million dollar a can stop leak is NOT going to help you.

If the system is empty and you don't have access to a vacuum pump, your pissing in the wind and should stop right there.

If you do..

what i would do is get a compression fitting removal tool if you don't have one. Break the fittings from the condenser and accumulator. Replace all the orings. look for damage or deterioration . replace all of them. Orings are cheap.

Look closely at the condenser in front of the radiator. Look for big dings in the front of it from object imacts. Look for any area that looks oily or has accumulated debris. I just did a 95 LHS that i had to pump down and refill 3 times. The condensor turned out to be leaking in the lower drivers side corner. You could see where it was oily in that area and gunk was stuck to it.

Buy a UV flashlight and goggles from the auto-parts store. When you refill it, put UV Dye into the systems, charge it up and run it for

1/2 hours or so if you can. Then let it cool down and get the UV flashlight out and look for telltale signs of a leak. It illuminates leaks like a blacklight poster. Its easeir to see at night or in lower light if you don't have a large leak.

Harbor freight frequently has R134 gauge sets on sale for a reasonable cost. It aint snap on or robinaire, but it will do for the home mechanic.

bob

I have never had any luck with any of the stop leak products for AC systems. I'm not sure what mechanism would ever make them work.

There's unfortunately no substitute for finding the leak and fixing it. Put the dye pack in there, pressurize the system again, clean the whole engine compartment with engine cleaner, then start the thing up again and use the UV light in the dark to look for leaking tracer dye.

--scott

I used one that cost about $29 3-4 years ago on a friend's caravan. It worked at the time I did the recharge, and she sold the car a few months later. I don't know how long it held up.

It's been my experience that anything that says "stop leak" that comes in a can or a bottle is usually just a temporary fix, if it fixes the problem at all. It's usually better to find the problem and repair the broken parts instead.

Good luck with it,

Sometimes they will work for a while, Scott. They may get you through a summer, or even longer, but in other cases like this one, they dont hold overnight.

It would have been good to know what unit the OP was talking about. As you know, some of the older GM compressors would start leaking at the shaft and there was nothing to do but change it out, or sweat.

If you have a hole in an evaporator core, nothing but changeout is going to stop that

I havent had any luck at all with dye in HVAC systems. Neither was I able to see the change in the old propane Freon sniffer systems. With the new electronic sniffers, you could find one honest politician in a nominating convention (if there were one)

The dye seems to work okay IF you clean the inside of the engine compartment enough that the dye isn't obscured by all the fluorescent crap from old coolant leaks and power steering fluid leaks under there. Steam cleaning will do.

The old propane jet seems to work well if there is an enormous leak, but if there was that severe a leak you probably wouldn't need it anyway.

As a shadetree guy, I don't like AC enough to pony up for one of the fancy sniffers. I finally installed AC into the 2002 after twenty-odd years just because my wife was yelling about it.

--scott

Dye works fine. And I've never seen any other fluid "residue" fluoresce, so I don't even know what you're talking about there. Goes without saying that if your engine is all grunged up you better take care of what's causing that. There's a few things to make dye detection work. It' ain't magic. This is what has ALWAYS worked for me. First off, I use a dedicated dye kit.

23-104792442-2

You might find it somewhere else. That link is just to show what I use. I got a can for less than $10 somewhere I can't remember last time I bought it. First time I used it Oreilly's had it in kit form and it came with a UV penlight. But they don't carry that kit any more.

There's other dye kits, most for injecting through a gage manifold, but I never used them.

First get the car in the dark and make sure no old dye shows up with the light. If it does wipe it off. I've never found that dye to stick around more than a couple month. Might last longer in real dry climates. Shoot in the dye charge for a couple seconds per instructions, THEN charge up the system with 134. Use the light to find and wipe off any dye that might have sprayed around the shrader valve. If the leak is a slow one, you want to wait a few days before putting a light on it to find the leak. Don't be driving in the rain before you put the light on it. Be in the dark when you put the light on it. The penlight that came with the kit is weak, but usually works to find the leak. A strong UV light works a lot better. They're cheap. Maybe $10. Start at the shraders, follow hoses, check the compressor fittings, shaft, dryer fittings etc. For the condensor you may have to remove shrouding to see everything, and you should crawl under the car with the light to see under everything to get a good look. If you find a leak, don't stop. May be another. Only bother going to the evap if you haven't found a leak. Works every time.

Dye may work fine if the engine is clean and the leak is in a place where the residues can be seen.mm Sometimes this isnt the case.

A LOT of other liquids fluoresce.....in particular, molecules with aromatic nuclei or fused aromatic rings, which are common in used motor oil.

That's a pretty slow leak.... I have never waited a whole week in order to look for the dye, though. Maybe I should....

You don't have a lot of dirt roads out there, I gather.

In fact I have also used the Interdynamics dye. So my guess is either I'm not patient enough or your vision is a lot better than mine. And my vision has never been all that great.

--scott