Can replace ONLY the A/C seals?

airconditioning

#1

Last summer a mechanic added 1 pound refrigerant to my '97 Geo Prism (Corolla

twin)'s A/C system & it got me thru the summer. I was told there must be “a hole

somewhere in the condenser” but I declined their suggestion of replacing the condenser.

Now there’s no cold. Unfortunately I didn’t read & follow my Haynes Repair Manual’s advice to run the A/C “for about 10 minutes at least once a month–particularly important during the winter” so I assume the seals have hardened over the years & are causing some leakage.

Is it possible to replace ONLY the seals, not the entire condenser? Where exactly are they located?

--Davide near Detroit


#2

Yes, it’s possible to replace the seals, and if that’s what is leaking they should be replaced. If the condenser is leaking, it needs to be replaced, and seals alone will not help.

I hope the mechanic who recharged it added dye so he/she can now see where the leak is. If not, find another AC mechanic.


#3

By the way, if you used the defroster over the winter you ran the AC compressor. The compressor runs whenever you select “defrost.”

The seals are located where the AC lines attach to the condenser. This is not a do-it-yourself project. Find an AC shop with all the proper equipment and knowledge, and let them fix it. Then you won’t have to add refrigerant again next summer.


#4

Before replacing seals, look at the joint first. If it is clean and dry, chances are there is no leak there. Since some oil circulates within the system, wherever there is a leak a film of oil should accumulate and collect some dirt. Anyway, it’s not perfect but that’s a quick and dirty way to find leaks in the system.


#5

I hate to say it, but unless you are really equipped to do AC work, you are probably wasting your time. Take it to a good shop, let them diagnose the problem and tell you what needs to be done, then you can decide on the next step. It may be expensive, one of my cars is currently in the middle of a $1300 AC repair.


#6

$1300 for what?

A hose for my wife’s benz (about $500), a few pounds of R-12, a receiver dryer, a new pressure switch, and some labor. The usual.

It would by cheaper to DIY, but I don’t have the time, equipment, or interest to do AC work.


#7

It sounds like someone is wild guessing on this leak. The condenser receives high pressure liguid and usually if a hole develops in the condenser there will be an oily blotch wherever that hole is located.

The usual suspect on compressor system leaks is the air compressor shaft seal. The shaft seal kit is replaceable without replacing the compressor.

I would say determine where the leak, or leaks, are actually at and go from there.


#8

Has anyone other than me used a stop leak and leak detector on their A/C system before? I’ve used it on my Lincoln after changing out the A/C compressor and orfice. Vacummed the system down and it held 29" of vacumm for several minutes but in two days it had leaked off the refrigerant. Put a 3 oz can of stop leak and leak detector in it and topped off with freon. It’s been holding for over a month now. Blows 50 degree air out of a/c vents!


#9

You need to get someone to put a set of gages on this to see what pressures you have to see if it is in fact low on freon before adding anything more to your A/C system.


#10

When watching a vacuum to detect whether a system is holding or not, you should wait longer than a few minutes; usually at least 15 minutes.

I use an electronic sniffer rather than leak detectors or stop leak.
Stop leak MAY possibly help on a dried O-ring but will do nothing for compressor shaft seals.

What may have happened is that your leak could have been in the service valve fitting (hanging a bit, piece of contaminant, etc.) and the problem was straightened out when you added the stop leak/detector.


#11

Took my van to the shop recently. They said the compressor seals were leaking and suggesting trying a stopleak that had dye and a seal refribersher (sp?). Either that or replace or rebulid the compressor. 3 weeks later and the AC is working great. Call around, AC shops can charge very different prices. Request a price for a specific repair like replacing the condensor and then ask if they will do a leak test to ensure that is the problem. Stay away from Pep Boys and the big chains. I haven’t had much luck there over the years.


#12

I followed the guidelines that a certified A/C tech gave me. If you don’t lose vacumm after 3 or four minutes it is highly unlikely that you would have any at 15 minutes. JMHO

I checked the valves with the “spit test”. They were not leaking at that time.


#13

And use a micron gauge (electronic vacuum gauge that can measure deep vacuum very accurately) instead of relying on the vacuum side of your refrigerant gauges.


Even a very small leak will usually be detected by a vacuum gauge. (But not always - that’s why nitrogen pressure testing is done.) With R134a systems, it’s even more important to use a micron gauge as moisture left in the system will react with polyol ester oil to form destructive acids. Pull a vacuum below 500 microns and have it hold for a few minutes and the moisture will be gone.


#14

Is this the same certified A/C tech who made a wild guess about “the condenser must have a hole in it”?
For what it’s worth, I’m A/C certified also and was trained in the 15 minutes thing years ago; 30 minutes is even better.

Obviously the suggested 3 minutes did not catch a slow compressor shaft seal leak.
The same thing applies to a cooling system test; no way should the system be pressured up and then call it good after 3 minutes.

I would avoid the stop leak products; the chance of it doing any good at all is near zero.
The shaft seal is a multi-piece part. The rubber O-rings could, in theory, be rejuvenated a bit with an additive, but the other part of the seal is spring loaded hard carbon and there is no substance on earth that is going to cure that.


#15

As others have suggested, you need to shoot it up with leak detector and look at the system under a black light after running it for a while–this should reveal where the leak(s) are. You can also look for oily patches at joints/connections–when refrigerant leaks, it tends to take oil with it. It may be cheaper to just dump in a can or two of refrigerant every summer until you’re ready to get rid of the car. I’d stay away from ‘stop leak’–in my experience, these do nothing but gum up the system and its sensors. Some shops may refuse to work on it if they find anything but refrigerant in the system as well.


#16

ok4450, I may need to clerify some things. One is I’m not the one who said that their A/C tech said there was a hole in the condenser. I also should have said that I vacummed down the system for 30 minutes and maintained at least 29" of vacumm. I shut the Vacumm pump off and left the gages hooked up and it maintained the 29" of vacumm for 3 minutes. I’ve used the stop leak and leak detector on both of my cars and so far they have not had any problems yet. I will also state that you can over do it with the stop leak. You can buy R134a with stop leak already in it. So if you use this type of R134 do not install anymore in it. Hope this clerfies things.


#17

I’ve used it too.
Holds leaks great!
Tends to jam up orifice tubes though. angry
50? isn’t exactly cold unless your outside temp is close to 100? or you’re sitting still at idle.
It’s better than nothing of course.
Leak sealer may help you but 1lb/year might be too much to seal.
But then again, at less than ten bucks it’s worth a shot.

There are seals all over the A/C system. At every hose fitting, and on the compressor shaft. If you’ll be replacing any seals you will have to have the refrigerant discharged and recovered. That’s gonna run you between 30 and 50 dollars if it’s anything like here in Daytona. Then you should replace ALL of the seals including the hose to evaporator, hose to condensor, accumulator, orifice tube, and the suction and discharge line seals on the back of the compressor. The accumulator and the orifice tube should be replaced before the system is closed up. Have a shop evacuate it for you, then you can charge it up.

-Matt


#18

Yes it was about 95 degrees outside and it was at idle also.