Air Conditioning Leak Investigation, Help Needed!

[83bj60]

Hey Folks,

Turns out that after the starter overhaul I did after my AC refill, the system is empty again three days later.

To those who have had experience with AC on the 80, or on any vehicle for that matter, any hints and any help would be appreciated before I tear it all apart, it's my first attempt at repairing an AC system.

I'm located in Canada and have the JDM model, but the reason I'm specifying the country is that the system was filled from empty with Duracool (hydrocarbon refrigerant), so no need to talk regulations here, there are no CFCs in the system at this time, and Duracool is fully legit here (as it is in many US states BTW).

BTW, when it was first refilled, it cooled like mad for a few minutes until I had to stop it to take care of my sticky starter, so I know the system works, it's just that it leaks.

I have done some searches on the subject here on MUD, but haven't found much so far. Any help, any nudge in the right direction would be appreciated.

Thanks in Advance,
Chris

[Rookie2]

You've got to find out where the leak is before you can fix it, so I would guess start off by charging it with leak detector. If it's letting out in 3 days, thats a pretty good size leak.

[Radd Cruisers]

If you have opened your system for any reason you should be - at least - drawing it down under vacuum for 30 minutes or more. Once you have established a good vacuum, you should then let it sit with the vacuum applied and see if there are any leaks in the system - which usually show up very quickly while under vacuum. If, and only if, you have no leaks should you then refill the system with refrigerant.

There are many potential problems with A/C systems - you are offering very little information about the problem. The first place to look, however, is where you opened the system up: look for O-rings that went missing, fittings that are not snug etc...

Good luck,

~John

[rchalmers3]

What Radd Cruisers said and you should be able to see the A/C system lubricating oil collecting near a big leak.

Throw another charge in it, run it and shut it off and listen with your best pair of ears. A three day leak is pretty obvious!

Rick

[83bj60]

Originally Posted by Radd Cruisers

If you have opened your system for any reason you should be - at least - drawing it down under vacuum for 30 minutes or more. Once you have established a good vacuum, you should then let it sit with the vacuum applied and see if there are any leaks in the system - which usually show up very quickly while under vacuum. If, and only if, you have no leaks should you then refill the system with refrigerant.

There are many potential problems with A/C systems - you are offering very little information about the problem. The first place to look, however, is where you opened the system up: look for O-rings that went missing, fittings that are not snug etc...

Good luck,

~John

OK, sorry if I wasn't clear enough.

I did not open the system. It's been empty for a long time, and I just refilled it for the first time a few days ago. It worked perfectly after I refilled it, but three days later, the system was empty again, zero pressure. So it's got an obvious, pretty substantial leak.

Vaccuming the system is not necessary when using Duracool, especially if the system was empty before; there is no need to reclaim the old refrigerant, there isn't any!

Besides, I wouldn't vaccum a system with a major leak, it would pull in moist outside air into it.

Before I got the can of dye or refill the system again and look for leaks with soapy water, I thought I'd ask for common fail points. Like, does it usually leak at the compressor, the evaporator or the condenser? Maybe at the pressure switch, the dryer or the expansion valve? I'm trying to figure out, before I dive into it, whether it's usually a fairly easy job with this vehicle or if it's a nightmare requing substancial dismantling, if it's even worth it at all.

In other words, what are the usual suspects, what common faults should I be looking for and culprits should I be looking at in priority?

[83bj60]

Originally Posted by rchalmers3

What Radd Cruisers said and you should be able to see the A/C system lubricating oil collecting near a big leak.

OK, good point... What does refrigerant oil look like? I did notice a bit of faint black build-up around the main outlet of the compressor... Could this indicate a decayed o-ring?

Originally Posted by rchalmers3

Throw another charge in it, run it and shut it off and listen with your best pair of ears. A three day leak is pretty obvious!

Rick

I'm sure it did not make a single hiss after the first refill. I just hope the fault is not behind the dash...

[TX Cruiser]

The manifold plate is an area that fails, also check the schrader valves, and the connections at the drier, condenser, and fire wall. The evap and expansion valve are pretty hard to check. If you are really handy you can put compressed air into the system and find the leaks with either your ear or soap and water. If your compressor is covered in black filth or oil from the pulley back, you may have a blown front seal. As mentioned above, look for the dark spots where normally it wouldn't be terribly dirty, this will indicate where oil got blown out, and remember to put some back in if you value the life of your compressor.

I would and do (especially if I put air or nitrogen in to the system to check for leaks) vacuum every system down, regardless of the refrigerant type.

[flintknapper]

I hope you will take no offense at what I am about to say/suggest...but IMO, you need to take your vehicle into a respected A/C shop and let them diagnose your problem.

I encourage and promote owners to work on their vehicles as much as possible, but it is clear to me that you don't have the tools or knowledge necessary to do this job "correctly".

Once the problem areas have been identified...you can do much of the work yourself (replace parts, etc) and then let the shop pull a vacuum and recharge the system.

There IS a correct way to do A/C work (and good reasons for doing so). Pulling a vacuum on the system has nothing to do with what type of refrigerant you have in it. Gauges (and only gauges) will tell you what your system is doing (provided you know how to read them).

Every summer we get a dozen or so posts here asking for help (which is great...we are happy to help) and every summer we get an equal number of well meaning posts suggesting ways to fix things... that are far from professional standards and practices.

Repairing/Recharging/Retrofitting an A/C system correctly (the first time) is not a matter of just buying some refrigerant and "pouring in the cool".

Please have a professional look at it. It sounds like you have several problem areas... all of which will require equipment and experience.

[Tools R Us]

Finding a fast leak is much easier than a slow one. I just did the wife's Camry today and it was the squarish o-ring on top of the compressor. I have a hose that adapts from shop air to the gauge set, filled it with shop air and found the leak with soapy water.

[flintknapper]

Edit:

Nevermind.

[83bj60]

Originally Posted by flintknapper

I hope you will take no offense at what I am about to say/suggest...but IMO, you need to take your vehicle into a respected A/C shop and let them diagnose your problem.

I encourage and promote owners to work on their vehicles as much as possible, but it is clear to me that you don't have the tools or knowledge necessary to do this job "correctly".

Once the problem areas have been identified...you can do much of the work yourself (replace parts, etc) and then let the shop pull a vacuum and recharge the system.

I appreciate your advice and it would be perfect in an ideal world, however it always ends up with the 'expert' taking over. Thank You, but No, Thanks.

Small garages were you could actually participate with the mechanic are almost all gone now, because of insurance and regulations. It's a global trend to divest responsibilty away from the user. Just like modern computer OSes, that prevent you from doing what you want 'for your own good'. Heck even the 'custom' muffler shop that used to build systems from scratch now refuses to do anything that deviates from the 'approved factory routing' they have in their books.

So I'm not taking offense personally, but I won't tolerate being talked down and taken for an idiot either. I've been in technical occupations for all my life and see that kind of fear-mongering all the time, and I dismiss it because I believe true freedom comes from empowering people by passing on knowledge they can use to solve the problems they encounter by themselves.

Unless of course, you don't want to tackle that problem, that is. For example, I categorically refuse to 'understand' government formwork and to do it myself, hoewever 'easy' they try to make it look. It's basically nonsense to me so I have 'experts' do it for me.

So please don't you take offense with my personal attitude towards your philosphy, I can see you are well meaning, but I respectfully and strongly disagree with it it.

[flintknapper]

Originally Posted by 83bj60

I appreciate your advice and it would be perfect in an ideal world, however it always ends up with the 'expert' taking over. Thank You, but No, Thanks.

Thats kind of the idea here. If you already knew what to do and how to do it....then you wouldn't be here soliciting advice. I'm just trying to save you a headache and probably some money.

Small garages were you could actually participate with the mechanic are almost all gone now, because of insurance and regulations. It's a global trend to divest responsibilty away from the user. Just like modern computer OSes, that prevent you from doing what you want 'for your own good'. Heck even the 'custom' muffler shop that used to build systems from scratch now refuses to do anything that deviates from the 'approved factory routing' they have in their books.

Yup, as a direct result of the litigious society we now live in, shops no longer allow customers access to their work areas. Just a fact of life.

So I'm not taking offense personally, but I won't tolerate being talked down and taken for an idiot either.

I don't know if this directed at me, or is in addendum to your position concerning small shops and computers above. If for me, I can assure you I am not "talking down" to you or have any presumption about you being an idiot (or not).

I've been in technical occupations for all my life and see that kind of fear-mongering all the time, and I dismiss it because I believe true freedom comes from empowering people by passing on knowledge they can use to solve the problems they encounter by themselves.

Well, thats a nice speech....but it won't do anything to help keep you cool if you muck things up because you wouldn't accept good advice.

Unless of course, you don't want to tackle that problem, that is. For example, I categorically refuse to 'understand' government form-work and to do it myself, however 'easy' they try to make it look. It's basically nonsense to me so I have 'experts' do it for me.

I can't speak to "government form-works", so unless its required of you to work on your vehicle and not just an analogy of yours, then I'll just disregard it.

So please don't you take offense with my personal attitude towards your philosphy, I can see you are well meaning, but I respectfully and strongly disagree with it it

Friend, this is not a matter of philosophy. It is a "recommendation" based on years of observation and experience concerning folks "trouble-shooting" their A/C systems.

I am NOT trying to discourage anyone from working on their own vehicle and/or learning a new skill. However, "most" A/C work requires certain tools/equipment to properly diagnose and service the system. It doesn't sound like you have these things.

From the little information you have given us, you have a "serious" leak in your system. You might in fact...have several "leaks", not just one. As you have already discovered, simply putting more refrigerant in...is an exercise in futility.

Since you have completely lost your "charge" twice already... do you know how much oil you have left in your system? Do you need to add some? If so...how much?

If the leak turns out the be the front seal on the compressor, do you have the tools and know how to install a new unit. If yes, great....if no, then not so great.

Do you plan on replacing the receiver/dryer? Do you know why that is important?

Do have a vacuum pump (or can rent one) and do you know how to use one? Or maybe you were going to count on the drying agents in the "DuraCool". Do you know that moisture mixed with fluorocarbons forms hydrochloric acid? Wanna know what hydrochloric acid does to the inside of your A/C system?

Now, you can call that "fear mongering" if you like, but in reality it is "knowing what you're doing".

Do you own a set of manifold gauges (or will rent some)? Do you know how to read a set of gauges when you get them?

If for some reason your A/C system needs to be "flushed" do you have the equipment to do that. Do you even know what it involves? If not, then "having worked in technical fields all your life" doesn't really count for squat, right? I can appreciate that it demonstrates a propensity/aptitude on your part for "learning" which is wonderful (if you are willing to study the subject).

The bottom line is this: Your situation is one that involves "trouble-shooting" your A/C system...and not simply matter of just "topping off" the refrigerant (something any 9 yr. old can do). It may turn out that you have an easy to find leak that can be quickly repaired. Or, it may turn out to be several leaks accompanied by other problems as well.

If you've done A/C work before...and have the tools, then by all means "get after it". If not, then you might be money and time ahead by taking it to someone who does this on a regular basis.

That was point of my post. Do as you wish, best of luck.

Flint.


P.S.

Radd Cruisers wrote:

If you have opened your system for any reason you should be - at least - drawing it down under vacuum for 30 minutes or more. Once you have established a good vacuum, you should then let it sit with the vacuum applied and see if there are any leaks in the system - which usually show up very quickly while under vacuum. If, and only if, you have no leaks should you then refill the system with refrigerant.

There are many potential problems with A/C systems - you are offering very little information about the problem. The first place to look, however, is where you opened the system up: look for O-rings that went missing, fittings that are not snug etc...

Good luck,

~John

This man definitely "understands".

[83bj60]

It's all fine and dandy, but you are dismissing parallel thinking as a problem solving method. But as I said, I can understand your point of view: most people don't 'work' that way and need guidance and to blindly follow 'instructions' along a straight and narrow path.

I don't function that way. I prefer to gather factual evidence, diagnose the true causes and understand the principles at work in order to determine the proper course of action, rather than to rely on opinion and belief.

[flintknapper]

Originally Posted by 83bj60

It's all fine and dandy, but you are dismissing parallel thinking as a problem solving method. But as I said, I can understand your point of view: most people don't 'work' that way and need guidance and to blindly follow 'instructions' along a straight and narrow path.

I don't function that way. I prefer to gather factual evidence, diagnose the true causes and understand the principles at work in order to determine the proper course of action, rather than to rely on opinion and belief.

Jesus............., I can tell this isn't going to work for you at all.

Please let us know if we can be of any help to you down the line.

Good luck Sir,

Flint.

[Sc0-]

Any/all hose connections have the O-rings, if the system has been empty for awhile I would replace all of them. A/C Compressor seal, not so easy to replace and is a royal PITA if it is leaking and am not sure you can buy one separate and install it.


From what I know: (use at your own risk disclaimer)
Refill with dye and use special UV light and look for the leak, soap bubbles are OK but specialty items require special tools. Check the Schrader valves as well, they also have O-rings that can leak so make sure they have caps on to keep the crud out and pressure in. I have retrofitted two cars and repaired one, and am about to purchase more "special" A/C tools as I am tired of barrowing them. You can "short" the compressor pressure switch to help pull a vacuum on the system which helps a little.

[83bj60]

Thank You ScO for the practical information. It's much appreciated!

In this day and age were everyone is going mad with and everything gets paralysed by disclaimeritis, I've always done everything at my "own risk", otherwise I wouldn't have bought a right hand drive vehicle, sight unseen, and brought it over, with no local support, to one of the most conservative, socially monolithic and regulated provinces in this country.

Thanks for the pressure valve tip, and thanks for reminding me about the sharader valve, makes a lot of sense, I've seen them fail before.

You should check out the Duracool site. I like their philosophy. Not only does their refrigerant bypass the regulatory bullshit, as it's totally ozone friendly, but all their products are designed to fix the problems arising from the use of these refrigerants. Heck, not only do they have dye products, they also have two grades of sealants depending on leak rate. They're pretty smart, AND they guarantee their product IN WRITING...

[flintknapper]

You find that leak yet?

[83bj60]

I've been researching this a bit further and found a supplier on the internet for gaskets and o-rings, I was glad to find out it's fairly inexpensive. Next step is to look for these supplies locally, including a dryer and dye. I want to be ready and have it all at hand before I start open things up. It's obvious at least one gasket or o-ring needs to be replaced and I'll check for signs of compressor wear when I open it up to replace that gasket or o-ring.

The way I'm planning it is, get all the parts, fill with leak detection dye, locate the leak(s), replace gasket(s) or o-ring(s) and look for signs of compressor wear.

If there is apparent wear I'll have the system professionnally flushed. Otherwise I'll evacuate it with my friend's vaccum pump before refilling with duracool again.

I'm not expecting to really 'save' by doing it myself nor am I adamant to 'avoid problems'; my goal is to learn how it works and how to do it. Time taken to achieve this goal is irrelevant.

In the mean time I'm very busy this week so it may not be done for a few weeks. I'll update this next time I work on this project, in the meantime I'll keep reading, so keep your suggestions coming