A/C system - how to remove the cooling unit, evaporator, expansion valve (3 Viewers)

[Schmutz]

Further inspection revealed a mouse nest in the fan area. Check this out...

Those are the desiccated remains of two baby mice

Otherwise the project went smoothly, thanks to the collective wisdom of 16 pages of this thread The evaporator core and case were removed easily and painlessly. The tip to remove PS front seat helped tremendously. Obviously I removed the offending mouse-debris and thoroughly cleamed out the core with compressed air. New O-rings were lubed with Mineral Oil, and I added .5 oz (or 14.79cc) of PAG oil to the new Receiver drier.
I did remove the DS headlight for easier access to Drier location, but that also facilitated another task —repainting the chrome trim around the lights. Reassembly was without drama. Evac’d the entire system and it held a vacuum. Our Harbor Freight pump couldn’t quite achieve the recommenced -29Hg but the RobinAir gauges showed -25Hg. Recharged the system with 3 cans (36oz) of R-134a. The AC system did its thing, and once everything stabilized, the HP line showed 190psi and LP line showed 35psi, (while running) with cabin air temp of 39 degrees. I’m thrilled with that!

Again, my sincere thanks to all who contributed to the collective knowledge of this thread. Without it I would have taken my 80 to an AC specialist, and would be significantly poorer now

 

[alia176]

Awesome!!!!

 

[Landseer]

Our Harbor Freight pump couldn’t quite achieve the recommenced -29Hg but the RobinAir gauges showed -25Hg

The manifold gauges show gauge pressure - the pressure difference between the system pressure and atmosphere pressure. Essentially the manifold gauge is showing how far below atmospheric pressure the system is, so the pressure reading for full vacuum will vary with elevation. If you're at sea level full vacuum is 29.9 in Hg, at 5,000 feet full vacuum is 24.9 in Hg.

 

[Schmutz]

If you're at sea level full vacuum is 29.9 in Hg, at 5,000 feet full vacuum is 24.9 in Hg.

In that case, I hope we got close enough, coz my garage sits at an altitude of 4, 749 ft

 

[onemudder]

Nothing against Beno and Dan (I order from them), but Rock Auto has DENSO Receiver and Driers, DENSO Expansion Valves, and DENSO Condensers for cheap cheap cheap. I did a component each night after work. Since I didn't have gauges and pump, had local shop refill for $70. Cleaned the Evap core with Mean Grean then blew dry with air compressor. Not too bad of a job if you take your time. Put in the UV PAG oil and you can find your own leaks with a black light. Fittings are to get Mineral oil before assembly. If you had compressor failure I would blow lines clean with some solvent to avoid contamination. Cleanliness is next to Godliness.

Good stuff. When you blow the lines what areas would you start with? I had to replace a rotted/pitted line on the DS front wheel / door last year. The connections down there are a PITA to loosen plus it’s tough accessing them sometimes.

I bought a compressor attachment called “tornado” or something IIRC I saw someone blow out but can’t find anymore.

I’m about to do an entire replacement of parts on my 2006 LC and want to get this right. Not to overdo it but at least a good portion of it being blown out since the broken line down there was openly broken for awhile before I got to replace it.
Thanks in advance.

 

[Red Merle]

So I went to recharge my system as it lost some refrigerant over the course of the last three years since I replaced everything and I accidently bought a can that had the sealer stuff in it. I wasn't paying attention at the store and didn't realize that a can of that stuff had gotten mixed in with the normal stuff.

Anyway, it's in the truck now. How bad is this? I have read that it will clog up certain parts of the system, namely the expansion valve and maybe the drier.

Has anyone used this stuff and not had issues? The AC is cold right now but I think it needs a little more r134a, probably one more can. Should I even bother with that or am I looking at cracking the system and flushing it all out and starting over?

 

[flintknapper]

So I went to recharge my system as it lost some refrigerant over the course of the last three years since I replaced everything and I accidently bought a can that had the sealer stuff in it. I wasn't paying attention at the store and didn't realize that a can of that stuff had gotten mixed in with the normal stuff.

Anyway, it's in the truck now. How bad is this? I have read that it will clog up certain parts of the system, namely the expansion valve and maybe the drier.

Has anyone used this stuff and not had issues? The AC is cold right now but I think it needs a little more r134a, probably one more can. Should I even bother with that or am I looking at cracking the system and flushing it all out and starting over?

How much internal restricting it does (or not) would depend heavily upon how much moisture is in the system. Since you were low on refrigerant....it is safe to assume you have a slow leak someplace. IF the system has gotten substantially low on pressure....then chances are some moisture has entered the system. The desiccant in the drier will capture the moisture (up to its saturation point) but we would have no way of knowing if the rest of system has also been affected.

The issue with moisture in the system (beyond the normal troubles it causes) is that most of these sealers are 'moisture cure' products. So they will harden (set up) after any contact with moisture. That might be OK if you only had a small pin hole leak in a line and the product only hardened when it met the moisture in the air and/or the condensation on the outer surface of the line.

BUT it will make no distinction between moisture in the air or moisture in the system. So the most likely areas to suffer are the drier, the TXV and the Evaporator. The sealers CAN actually plug some smaller holes in lines but will not fix leaks around O-rings or the front seal of the compressor....which account for most leaks (other than shrader valves).

I simply don't know if there is a flushing agent that reliably removes/dissolves any liquid parts of the sealer that are in the system now. I do know that shops with recovery machines have special separators to capture dyes, sealers and additives and they definitely want to know if any are present. So you might contact a Pro Shop and ask their opinion. They might tell you 'wait and see' or might recommend moving on it right away. The general consensus among pro's is that sealers are bad news (of course you knew that).

 

[Red Merle]

How much internal restricting it does (or not) would depend heavily upon how much moisture is in the system. Since you were low on refrigerant....it is safe to assume you have a slow leak someplace. IF the system has gotten substantially low on pressure....then chances are some moisture has entered the system. The desiccant in the drier will capture the moisture (up to its saturation point) but we would have no way of knowing if the rest of system has also been affected.

The issue with moisture in the system (beyond the normal troubles it causes) is that most of these sealers are 'moisture cure' products. So they will harden (set up) after any contact with moisture. That might be OK if you only had a small pin hole leak in a line and the product only hardened when it met the moisture in the air and/or the condensation on the outer surface of the line.

BUT it will make no distinction between moisture in the air or moisture in the system. So the most likely areas to suffer are the drier, the TXV and the Evaporator. The sealers CAN actually plug some smaller holes in lines but will not fix leaks around O-rings or the front seal of the compressor....which account for most leaks (other than shrader valves).

I simply don't know if there is a flushing agent that reliably removes/dissolves any liquid parts of the sealer that are in the system now. I do know that shops with recovery machines have special separators to capture dyes, sealers and additives and they definitely want to know if any are present. So you might contact a Pro Shop and ask their opinion. They might tell you 'wait and see' or might recommend moving on it right away. The general consensus among pro's is that sealers are bad news (of course you knew that).

Thanks for chiming in. You have the best advice on this topic from what I have read here so you are confirming what I already think I knew. Dang it.

I am not sure where it leaked out in the first place though. It held fine for 2.5 years but it was definitely low. I tried looking the other night with my UV light and I couldn't see anything obvious so my suspicion is that it is leaking at the compressor internally which I guess is common and makes sense.

I will have to find a shop that deals with this stuff and see if they can help.

Do you think I could just have them clean the lines and then I could do the rest of the work? It seems like if I sacrifice the drier that would work, if it works at all.

 

[flintknapper]

Thanks for chiming in. You have the best advice on this topic from what I have read here so you are confirming what I already think I knew. Dang it.

I am not sure where it leaked out in the first place though. It held fine for 2.5 years but it was definitely low. I tried looking the other night with my UV light and I couldn't see anything obvious so my suspicion is that it is leaking at the compressor internally which I guess is common and makes sense.

I will have to find a shop that deals with this stuff and see if they can help.

Do you think I could just have them clean the lines and then I could do the rest of the work? It seems like if I sacrifice the drier that would work, if it works at all.

Places where leaks occur that can be difficult to spot are the front seal on the compressor and the evaporator (since it is housed) but even some condenser leaks can be tough to spot. Yes, you can do the other work yourself.....you are mechanically inclined and have proven yourself a capable mechanic.

See what an A/C shop has to say about flushing the system....no doubt they've dealt with this before and can advise you. I know a little about HOW sealers work....but haven't ever been involved with a system that had it in there. So my list of 'possibilities' is just that. It may or may not be serious in your case.

 

[MANUCHAO]

I dont know much about sealers, but best thing you can do to remove non-condensables is to do a nitrogen sweep ( up to three times ) while at the same time see if you can spot the leak.... Best thing to do is stay away from dies and sealers..... I would def replace the dryer and TXV after flushing out the system Pulling a deep vacuum would be ideal, but only after making sure you dont have any leaks, otherwise you run the risk of pulling moisture into the system....

 

[Red Merle]

Places where leaks occur that can be difficult to spot are the front seal on the compressor and the evaporator (since it is housed) but even some condenser leaks can be tough to spot. Yes, you can do the other work yourself.....you are mechanically inclined and have proven yourself a capable mechanic.

See what an A/C shop has to say about flushing the system....no doubt they've dealt with this before and can advise you. I know a little about HOW sealers work....but haven't ever been involved with a system that had it in there. So my list of 'possibilities' is just that. It may or may not be serious in your case.

Yeah, I know I can rebuild it if I need to but obviously I was kinda hoping for more than two summers since I replaced pretty much everything the last time with the exception of the high pressure line.

I will have to talk to some places around here on Monday and see what they think. I can't believe I did this. The hilarious part is that I was at the store to return a can that I didn't realize had the sealer in it and I made the exact same mistake again. My only excuse is that I was hot because my AC wasn't cold enough on the drive there.

 

[Red Merle]

I dont know much about sealers, but best thing you can do to remove non-condensables is to do a nitrogen sweep ( up to three times ) while at the same time see if you can spot the leak.... Best thing to do is stay away from dies and sealers..... I would def replace the dryer and TXV after flushing out the system Pulling a deep vacuum would be ideal, but only after making sure you dont have any leaks, otherwise you run the risk of pulling moisture into the system....

I don't have nitrogen so I would be taking it somewhere for that. I do have the vacuum pump that I bought when I did this the last time so if I can get this stupid sealer out of there, I should be able to do the rest if they can pull a vacuum on it after they flush it.

 

[flintknapper]

Yeah, I know I can rebuild it if I need to but obviously I was kinda hoping for more than two summers since I replaced pretty much everything the last time with the exception of the high pressure line.

I will have to talk to some places around here on Monday and see what they think. I can't believe I did this. The hilarious part is that I was at the store to return a can that I didn't realize had the sealer in it and I made the exact same mistake again. My only excuse is that I was hot because my AC wasn't cold enough on the drive there.

I remember you doing all of that (AC work). Hopefully the shop can get the system flushed well enough that you can just replace the drier and system oil (PAG46), check for leaks, pull a vacuum and recharge. Please let us know what they say. And don't be too hard on yourself. We all make mistakes....especially if you have a lot on your mind. You'll work through this I know. You have more time working on your Cruiser than many of us....so we know you are tenacious.

 

[Red Merle]

I remember you doing all of that (AC work). Hopefully the shop can get the system flushed well enough that you can just replace the drier and system oil (PAG46), check for leaks, pull a vacuum and recharge. Please let us know what they say. And don't be too hard on yourself. We all make mistakes....especially if you have a lot on your mind. You'll work through this I know. You have more time working on your Cruiser than many of us....so we know you are tenacious.

Thanks for the encouragement! Yeah, I am pretty much done with my truck now that I finally got around to doing a full refresh on the suspension including all new bushings, new springs and shocks and full rust removal on everything underneath and then POR15ed. There really aren't any more systems left to replace now, but I guess now I am back into maintaining and redoing work I already did.

I will for sure let you guys know what they say because I am certain I am not the first guy to inject this stuff into my system, unintentionally or intentionally or a PO did it and now people are dealing with it. I am honestly kind of surprised they are even allowed to sell it, given how tight the EPA used to be when it came to letting shade tree mechanics mess around with the AC system when r12 was the deal.

 

[Red Merle]

First update. I said I would report back so here we are.

Talked to a known decent mechanic this morning and he pretty much confirmed everything said thus far and also declined to deal with trying to get the gunk out using his recharge equipment. Both guys there thought just letting it ride at this point is probably the way to go. If there was damage done, it's already done.

I think I am going to just add another can of the non sealant stuff and see what happens. It did get down into the 50's as far as temps go on my thermometer in the vent but I may still be low on refrigerant as I think a good amount must have leaked out. I will take more looks as I go with the UV light but I guess it's pretty normal for the compressor to leak a little which does make sense.

 

[flintknapper]

First update. I said I would report back so here we are.

Talked to a known decent mechanic this morning and he pretty much confirmed everything said thus far and also declined to deal with trying to get the gunk out using his recharge equipment. Both guys there thought just letting it ride at this point is probably the way to go. If there was damage done, it's already done.

I think I am going to just add another can of the non sealant stuff and see what happens. It did get down into the 50's as far as temps go on my thermometer in the vent but I may still be low on refrigerant as I think a good amount must have leaked out. I will take more looks as I go with the UV light but I guess it's pretty normal for the compressor to leak a little which does make sense.

I think your plan is a good one at this juncture. And yes, a system with any use/age to it is going to lose small amounts of refrigerant past the compressor seal (if not elsewhere) each year.

But I agree with your mechanics, forge ahead and see what happens.

 

[MYSHERPA]

Finally, two pics showing the removal of the A/C Dryer. This is a must if you're opening up the system and changing out the expansion valve.

Best access to the dryer is through the driver marker light. Tip: loosen the top two 10mm bolts first before opening up the bracket. These two bolts will very tight and will make the dryer move around on you unless it's still securely attached to the vehicle.

The FSM states to add 10 cc of PAG 46 oil to the compressor when replacing an expansion valve. Pay close attention to the FSM in regards to how much oil to add to the compressor when a A/C component has been replaced.

Sorry if I'm just dense, but why is removing the A/C dryer a must if you're changing out the expansion valve? Do you mean remove, remove? Or replace it with a new one, service it or what? I tried searching for the answer in the thread but it's 17+ pages long at this point.

 

[ZackR]

Sorry if I'm just dense, but why is removing the A/C dryer a must if you're changing out the expansion valve? Do you mean remove, remove? Or replace it with a new one, service it or what? I tried searching for the answer in the thread but it's 17+ pages long at this point.

Quick answer - If you open up the system then replace the A/C drier.

 

[bryson]

Replace the drier with a new one because moisture is introduced into the system when you open it up. That's my understanding.

 

[flintknapper]

Sorry if I'm just dense, but why is removing the A/C dryer a must if you're changing out the expansion valve? Do you mean remove, remove? Or replace it with a new one, service it or what? I tried searching for the answer in the thread but it's 17+ pages long at this point.

Zack answered it. Anytime you open the system to atmosphere (for a significant period of time) you should replace the drier. Or if the drier is old....its a good time to do it also. It contains desiccant that absorbs moisture, moisture is a bad thing to have in your A/C system.