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Been a long time since I Rock and Roll.... err... did AC work.

465 Views 18 Replies 4 Participants Last post by  ehbrown1
The time may have come for me to FINALLY show the AC system in my van some attention. It was on my to do list, and I even bought seals and refrigerant a while back, but I decided to spin a bearing instead. Now that it's back in one piece and the weather is getting warmer, this might just be the year I get it cooled off inside. It's been a LONG time since I did any real AC work, I cut my teeth on it when a can of R12 was 79¢ in the grocery store (Jeez... I'm 'THAT guy' now- lol).

I have front and rear AC, but only front temperature control. I DO have a separate rear blower switch, but not a thermostat. I THINK these are the parts I need. I DO have a rear expansion valve, hi side from the compressor only has one connection to a tee near the condenser, the low side has a tee mounted to the end of the single connector on the hose end at the accumulator. There is no muffler or service port on the lines. Given the amount of bending and the condition of the threads of the fitting after getting the accumulator detached, I'm going to replace the evaporator as well. This system has been effectively open since I got it in 2008. The compressor isn't locked up somehow, but I don't even want to do this once- let alone twice. At least my evap cover seems to be in really good shape. About the only parts I don't have in my cart are the liquid line, the lines to the rear evaporator, and the rear evaporator itself. I left a message for Rocky Ridge conversions, but I doubt they'll be any help. They do trucks now, and their website had no record of my VIN. I'm not surprised, it was done a long time ago.

So- am I missing anything here?

Do I need to add more oil to the compressor because it has rear AC?

I'll be hitting YouTube U over the coming week or two I'm sure.

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If still installed, why would you replace the rear stuff?
I fully understand the threads being ruined on a receiver/dryer on older vehicles, quite normal on GM's.
When it comes to the rear AC stuff, do you have stock or aftermarket?
It's been open a few years, the fitting on the back of the compressor was loose before that. Moisture had to have gotten to the expansion valve by now.

The stuff in the back is aftermarket. The heater core/evaporator had a sticker from Livonia, GA. I believe the company that converted the van was in Franklin, GA (Rocky Ridge conversions).
If aftermarket then that expansion valve is probably different than a factory one.
Hmmm, could be. If I'm going to the time and trouble of redoing the system I was hoping to have the rear ACworking too. Maybe I should just go with the front system then, I'd only have to replace the liquid line or find a cap for the extra port it has. Will just the front be adequate to cool the van?
Well, the more windows you have, the less efficient the a/c is. Also a raised roof or any volume change hurts it. In my experience, on hot days, people in the back can roast without rear a/c.
OK, first thing is to access the unit, see what type of valve it has, block or screw on tube mounted. Probably will have numbers on it. If not, it would not have to be a perfect match to work acceptable, as long as it can mount up.
Now if no signs of leakage, I would not worry about replacing the rear evaporator, I seriously doubt there would be but a little, if any at all, corrosion inside. Same with the lines to the rear, if metal I would not replace, you probably would have to hand make them anyway. If they used hoses, I would replace.
Anything not replaced to the rear, "open" up all connections, removing the valve, use some cans of flush on everything. Add a bit of oil, put back together.
Maybe I should just go with the front system then, I'd only have to replace the liquid line or find a cap for the extra port it has. Will just the front be adequate to cool the van?
That is a tough call, because you don't know the end results before you start. It definitely would be easier to fix and ensure a long functioning system with only the factory front AC. If you never have people in the back, well that would make the answer easier :)

It would definitely take longer to cool down, but once cool it should maintain the temperature in all but the hottest weather, so if you are planning on spending the hottest month of the year in death valley with 7 other adults in the van, probably want to fix that rear AC ;)
The choice is entirely up to you as to whether to remove the rear a/c or not. On those hot sticky days, it certainly does come in handy though.
Since the system has been open for some time, definitely replace the accumulator !!
Open every joint at connection points and check condition of the o-rings and look inside the tubing for foreign material.
If the other items look sound, condenser, evaporators, tx valve and orifice tube, no need to replace any of that unless damage or corrosion is obvious.
It would be prudent to flush the system as it has been opened for so long.

If the compressor turns without any grinding or binding, keep it.
Once reassembled, leak test overnight. If that passes, evacuate it for a good 24 hours to ensure ALL moisture is removed.

Look for a upfitter specification for charge size.
If you cannot find anything there, a factory system with rear air holds 3 pounds.
I would start there and adjust as pressures during operation dictate. Also add 2 oz of oil just as a precaution.
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Thanks all, definitely a lot of food for thought here. The compressor doesn't bind or grind when the clutch is turned by hand. The evaporator suffered a bit of bending getting the accumulator broken loose, making me question the integrity of the bend point. One of the rubber compressor lines has a spot where it appears to have been kinked for some time, I'd hate for that to develop a leak down the road. I've considered a JY replacement. The lines to the rear are rubber, and have been open since my engine swap in 2018 or so. The rear evaporator has also suffered some bending trying to get the valve off. I don't recall seeing any numbers on the valve except for 134A, I'll have to look at my pics again. It does look like a factory valve though.

My van does have a lot of windows. I've removed the middle row of seats and installed a larger electric seat/bed from an Express conversion van in the back for the rare times I'll need to carry people. So far I like having the extra room in the middle. My goals are to have working AC and be able to solo or couple camp for a day or three and not have to tow the popup, leaving the hitch available to bring the buggy along.
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So... I flushed the rear evaporator, all the lines, the condenser, the liquid line, but... when I tried to get the orifice tube out I destroyed the evaporator. I'm beginning to remember why I got rid of all my AC stuff years ago. The money this is costing would have bought a LOT of Slurpees and ice cream. 🥺
  • Wow
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So- evaporator repair kits are a thing now. Who knew? Amazon to the rescue.
How did removing a plastic orifice tube destroy the evaporator, if I may ask?
You must have suffered that "OH SHFF MOMENT" when trying to take the joint apart?
If you are forced to use an orifice tube repair kit, make sure you use a tiny bit of leak lock (blue goo) or liquid teflon sealant on the tubing before the crush sleeves are tightened. (Leak lock is designed to work with refrigerants).
That ensures you have a leakproof seal.

Then you're back in business.
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That is indeed what happened. I will have to find some liquid teflon, thanks for the heads up.

edit: I'm 99% sure I have a jar of this in the garage, think it'll work?
If you don't have Leak Loc, that's close enough.
You only need a thin film at the crush point, not much at all.
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I wonder about me sometimes. I really do. At least I saw it now rather than after it was vacuumed and filled, and I wondered why it didn't work.
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OOPS! That's definitely one of those OH SHART moments.
Hey, don't feel bad.
Done it once or twice (probably more) myself over the years.
Better then once you charge it and find you have 80 psi suction, no cooling and wonder what's goin on here.
Don't ask how I know.
Got it in, got it vacuumed, leak dyed, removed and bypassed a leaky pressure switch on the accumulator, held a vacuum, then the high side service port seal decided it was time to go. Figures, it's cooling pretty well. Thankfully the fitting has internal threads, a little Teflon tape and a bolt sealed it up nicely. No bubbles, even the Freon sniffer says it's sealed. I had to do a double take when I saw a puddle in the driveway between the fuel door and the rear tire- the rear AC drain is working, and has something to drain! The last time I saw that puddle was when the rear heater core froze. Unfortunately the rear evaporator and heater in this upfit are intertwined and no longer available, so we won't be enjoying rear heat in the future. I keep blankets in the van anyway. The heater hose holes will make a nice place to bring power up to an inverter whenever I get around to installing it.

Sorry if I'm rambling on about this, but this is the first time I've had working AC in my personal vehicle in decades. My wife's vehicles and my work vehicles have always had it, I'm used to driving beaters because I don't run up a lot of miles. 2000 in a year would be a lot for me. I usually log less than 1500, including 200-400 miles towing the camper. Maybe that'll change now. I doubt it, but one never knows.
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Sounds like success to me.
Enjoy that nice van-wide cold air.
Always a good sign when the water dripping under the van is from the a/c. REAL GOOD SIGN !!!!!
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