The shop seems unable to find the leak (apparently a slow leak. I had the system charged (R12) at the beginning of last summer and by summer's end, the AC wasn't blowing very cold. When checked a few days ago, there was a partial charge. The compressor, hoses, dryer, etc. are all new). The shop put dye in the system and I'm taking the car back in next week for a review. Any experienced AC guys with words of wisdom?

JamesC

 

did they put the green dye in it when the charged it? MY 87 does the same thing...never quite figured it out, BUT i had it converted to 134....now i can buy those little cans at the parts store and put a head on it myself.....R-12 is getting harder to find around here.........

 

not sure if this will help . i had the same problem with my 89r/s . turned out to be valve cores on the service ports . they are special sizes so don't try one for a tire . worked for me , good luck .

 

Had the same problem...turned out to be a leak in the compressor housing.. with the dye in tell them to look at the bottom of the compressor/bracket from under the car. I could only see the dye from under the car it didnt show from the top or side.

Still havent purchased the new compressor yet . Waiting to finish turbo install first.

 

Good advise about switching from R12 to R134a.. To actually test the A/C system they should have put the green or orange liquid in and charged with I believe 6 or 8 lbs or air to find the leak. Then, once they find it, Refill with refrigerant. Sometimes it is almost impossible to find, as is with you case.

 

I just rebuilt the ac system in my son't mitsubishi ...and the oil they gave me with the compressor rebuild had somekind of green dye in it......so it's there permanently....."lights up" when exposed to UV light........ of course the mitsu doesn't leak....only the camaro........which doesn't have dye in it!

 

My hope is that with the dye and a UV light, the shop will come up with something conclusive--I've fought the AC in this car, in one way or another including a conversion to 134 and back to 12, for a number of years.

JamesC

 

What exactly did you have to do to convert to 134?

 

Once you deplete the R12 that is currently or not currently in your system.. There is an adapter kit that is sold at almost all Auto Stores.. IE.. Autozone, Napa, Standard that costs around $12.. All you have to do is replace your low pressure side sitting with the new ones being careful not to destroy you A/C lines and then refill with the new R134 refrigerant. R134 is a great alternative as you can easily find it just about anywhere. You don't have to get Linseed oil or any additional lubricants. Just put in 3 small can's or 2 large cans and you are done.
1. Replace Fittings
2. Start Car
3. Turn A/C on
4. Install cans
5. Replace plastic caps
6. Enjoy the breeze providing your system is working 100% with no leaks

 

yeah what he said!!....or bring it to the shop and say "call me when it's done"!

 

Hopefully you won't enjoy the prices that they charge to refill your A/C though

 

definately cheaper if you do it yourself....the kits at most auto parts stores are pretty good and so are the instructions.........the shops in my area are actually pretty reasonable on charging a/c systems though..........

 

Okay...there's way more to a successful retro-fit than that. I do them quite a bit and to do it right you should replace all the o-rings at every fitting and oil them with ester oil prior to install-they'll seal better. The old ones shrink with age/heat. Next, install a new orifice tube, then install a new drier. THEN replace the fittings and pull in a vacuum down to 30" and shut vacuum pump off-if it holds that vacuum reading for over an hour, you are good to start charging.With wear and tear over the years, your old system WILL have small metal debris in the lines and mainly at the orifice tube. Do it right and do it once. A good compressor will draw the freon in fast. there's no debate in doing a R134 retro-fit...only one right way to do it.

 

Dont they have a froen sniffer that can detect the freon?If it lasted that long before leaking down it may be almost impossible to pinpoint.I know where my leak is and have replaced the o ring 3 times and it still leaks.Got tired of fighting it so i just had to charge it once a month or so on my truck.

 

Let us know the results of their findings.

James, you sound like the perfect candidate for Autofrost and a Cryochem R-134a kit. The kit is 4 oz of Tune Air and 4 oz of Cryo-seal. Costs about $170 or so for the Cryochem kit. This will fix your problem once and for all.

Don't be mislead by the R-134a kit name. They sell two different kits. One for R-22 and one for R-134a. The R-134a kit works with Autofrost.

The Tune Air will bring your moisture down to 0 ppm. The Cryo-seal will sense leaks by detecting moisture (at the leak) and then forming a patch on the outside of the leak. It's good for about 1 lb/week of leaking refrigerant. Seals leaks everywhere on the system except for compressor shaft seal leaks (since it is a moving part). The cryo-seal needs the tune air because if you don't have a completely dry system inside, the cryo-seal will simply activate inside the accumulator. Doesn't do anything bad. But it's a wasted product if you do that.

The Autofrost, I've written about before. 5-10° colder than R-12. Faster initial cooling down, due to having multiple temperature-pressure points in the condenser. (More area of the condenser gets used to reject heat compared to single refrigerants which have only one temp-pressure point)

The cryo-seal will plug leaks in the schrader valves while still allowing them to be used. It will re-seal the valves after they've been depressed. Or you could simply put some new valves in. They're cheap enough to replace.

Did you use Nylog on the O-ring?

 

If thats what the oil is called yes.Cant remember what it was called but i did use some kind of ac type oil.

 

go ahead and do that on your car. don't suggest that other people do it.

 

Honestly when you retrofit a system and have the system apart you should do the following
-disconnect your lines from your compressor, run some flush through the system.
-Replace your dryer
-Replace your orifice filter
-Try to get all the old oil out of your compressor
-Install Pag oil
-Charge system (keep in mind not to charge with can upside down, that is liquid and will damage your compressor put can with valve on top in some warm water)
-enjoy. Im sure im forgetting something.
A majority of times your shrader valves leak on charge ports and give you problems. Also be sure you have caps on the ports.

 

AC oil is typically mineral oil (R-12) or PAG or POE (R-134a cars).

Nylog is sort of like really sticky liquid glue. It helps seal O-rings and also stays in liquid form forever. It doesn't harden or dry. ackits.com sells it.

Don't forget to vacuum the system. It's essential!

You can get away with charging in liquid form. In fact, the blends require you to charge in liquid form. The key is to take your time. Let it circulate with the system running for 5 minutes (charging through the low side only) before adding that last can.

Never charge through the high side with the car running. The can will blow up and injure you. You can charge through the high side with the vehicle turned off though. For safety sake and forgetfulness, I tend to recommend simply using the low side only for all charging. Just take your time about it.

 

http://www.youtube.com/watch?v=vAULfI8-Wwk

Nylog video demonstration.

 

The reason you HAVE to pull the system into a vacuum is to remove moisture in the system which can freeze and damage the entire system. You simply have to do this step, no way around it. Now, suffice it to say if your system is constantly leaking, you are constantly losing vacuum...simply throwing a couple cans of freon at it is NOT a solution. After replacing your o-rings plus whatever else, pull the system down and with a set of R134 gauges hooked up, make sure after you turn the vacuum pump off that the low side reading does not creep up..at least this way you will know you still have a leak before wasting freon. Don't guess with stopleak....use a guage set/vacuum pump and pull an accurate reading.

 

Even with the sniffer and dye, the leak was untraceable. So the above suggestion may come in handy at some point.

JamesC

 

in my experience if you can't find the leak on the parts you can see it usually ends up being the only part you can't see, the evaporator. if you've really gone through everything else you can have it removed and tested, or just replace it if you can afford it.

 

You don't think the sniffer would have discovered a leak there?

JamesC

 

Sniffer can't really get to it cuz it's all enclosed.

 

Isn't that what the sniffer's all about?

JamesC

 

An evaporator leak would be extremely rare on our cars, you really never heard of any until about 1990-1, the EPA had them change the flux they used to solder them, and thats when they started to leak.

FYI, the only refrigerants the manufacturer's recommend are R134a and R12. The only oil the car and compressor manufacturer's recommend is mineral for R12 and the proper viscosity PAG oil for r134a. No one recommends any kind of stop leaks.

A proper retrofit involves more than just changing the fittings..

I couldn't tell you where the leak is coming from without looking at it myself. This is why it can be cheaper to just retrofit to r134a. Don't fool around with aftermarket refrigerants, ester oil and stop leaks, do a proper conversion.

I am not a big fan of the sniffer's they are VERY sensitive, just bumping the tip can set it off which makes finding the leak difficult. There are 3 other ways, you can use dye which is what I like, soapy water also works and with R12 you can use a propane torch (dangerous).

To check out the evaporator you might could take the blower motor out and take a look in there.

 

Has anyone tried the following product:

http://www.cliplight.com/automotive/...s&productID=16

JamesC

 

The manufacturers dont recommend it, and once you put a sealer in no a/c shop is ever going to touch it, it will damage their equipment.



http://docs.google.com/viewer?a=v&q=...EfjpxbOOA_VomQ

 

Yeahhh... That didn't work. So one of my components is junk. Got a quote from Autozone and $270 will ge me a new compressor, condenser and accumulator. Figure I might as well throw parts at it so I can have all new parts in a 25 year old car.

 

Those $3 cans of sealer that the automotive stores sell are just about guaranteed to be chewing gum, jello, crystals etc. All the stuff you showed in the pictures in your link.

The CryoChem product is invisible to a repair shop. It stays in the oil in liquid form forever. It can't change into the stuff described above. It is either miscible liquid or it's sealed the leak.

If a shop is serious about it's recycling machines, there are filters they can buy which sort out all the leak sealers, dyes, conditioners, and who knows what else is in some people's cars.

I've heard of it, but never used it. It seems similar to the CryoChem products except that it doesn't recommend you change out the drier before hand.

CryoChem at one point in time had a company make accumulators/driers that had no desiccant material in them, specially for use with the CryoChem products. The OEM's hated this as they lost out on the big money to be made in costly future A/C repair. With no desiccant, the CryoChem would always work as promised. (no chance of the Tune Air being activated in a water logged drier). So customers had a 0 ppm moisture A/C system that was sealed for good. Pretty much impossible for an acid eat out to ruin an A/C system when it was done like the above. And with a dry system, you'd get a performance boost in cooling temps which tends to keep customers away from shops. (Who has ever complained their A/C was too cold?)

I'm telling you James. You gotta go for the Autofrost/CryoChem combo. Get this forever leaking saga fixed. Driving to work in the morning these last few days (80°/83% humidity) the car was 65°. Not 65° duct temps. I'm talking the temp gauge on the seat was 65°. It's frigid. It's goooood. That was blowing 29° out the ducts (cycling). During the afternoon these last few days (100°, 4PM, sunny, traffic) it will still go down into the low 30's. It was blowing 41° by the time I pulled out of the parking lot at work this afternoon. I gave a co-worker a ride to his vehicle earlier this week and he commented that the A/C was colder than any car he'd been in.

Switching to R-134a wouldn't fix his leak problem though. It would just make things worse. Now he would have the problem of again trying to get all the old oil out, and then dealing with the so so performance that R-134a offers in our cars in southern climates.

The only window cleaner that GM recommends on vehicles is GM AC Delco window cleaner. Conveniently sold at your local GM dealer. Their recommendations are about maximizing money.