York compressor failure.. Brand freaking new unit!

[Beach_Dude]

Running like a charm! There's got to be a method or a warning to those that are replacing their evaporator core to remove the valve if their using a factory ac, and to cap off the Schrader if they have dealer installed ac.

As for the labor, I'm the guy that did all the tear down and rebuilding. Following tsm and every bit of literature to a t did not prevent this from happening.

As for the shops that charged, I was always told that there was a clog in the system and did the work myself.

I've driven it all day and the AC blows like a dream!

I'll update you guys in a few days... Usually my system would crap out after two or so days.

[FSJunkie]

Yeah, that would do it. Having the Schrader valve in there wouldn't be a problem if the equalization tube had a depressor inside it to open the valve, but it doesn't.

The new evaporators probably have the Schrader valve so they can be used on systems with and without the equalization tube. Many expansion valves are internally equalized. Once again, "universal and fits all" screws us. Always have to be diligent about new parts. That's why I reuse original for as long as possible.

Isn't it amazing how cold the vent air is when the expansion valve delivers the correct amount of refrigerant? You'd think more refrigerant would make the vent air colder, but it does the opposite. It makes for barely cool vent air while it freezes the crap out of the suction line and compressor, eventually destroying the compressor. Too little refrigerant cools poorly too. It has to be just right. That's the expansion valve's job. If your suction line to the compressor is cold enough to condense water but not freeze it, your refrigerant flow is just right.

A LOT of people are having this problem of poor cooling and ruining compressors, but many simply write it off as "old car A/C".

[SJTD]

Or that lousy 134a stuff.

[Beach_Dude]

Drove it on the freeway at 70mph and DA-HAM is that cold!!!

My girlfriend was freaking out saying it felt like a freezer being opened.

Just a little happy right now.

[Beach_Dude]

So, that's it, guys. I've been driving the General around for days and still blowing cold!!!

The only leak I have going is the evaperator coil, which SUCKS, because I don't want to have to drop the evaporator housing again. Also a brand new part.

A final piece of advice that I can give anybody is to buy a Freon sniffer off Amazon. Cost less than $30, and saves that price of freon alone for having to tighten all the leaks.

the prevention of this system like the back of my hand, so if anybody has any questions, feel free to reach out!!!!

Also, if you're in the Orange county LA area, and want to get your Freon pumped, reach out. I've got the equipment.

[FSJunkie]

I wouldn't spread that information around if I were you.

The EPA on a federal level is really cracking down on DIY air condition service. It's now illegal to buy more than a couple cans of refrigerant at a time, including a 30 pound drum, without a 609 certification, and any retailer who sells it to a person without certification is subject to a $44,000 fine. Retailers must photocopy the purchaser's certification and keep it on file in case of an EPA audit.

I know because I am a retailer.

The EPA has their goon squad out sniffing for people like you who might be servicing their own A/C without certification or without a proper recovery machine.

It blows chunks...hard.
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On a side note: yes, a proper functioning A/C system on these Jeeps works very well. It's a 2-ton refrigeration unit, which is about the same refrigeration capacity as a residential A/C system for a 1400 square foot house. That was standard for most cars back then, including all AMC cars. If you think that system does a good job of keeping your Jeep station wagon cold, you should try it in a little AMC Gremlin or Hornet with 20% tint on all windows like my Hornet is. I can freeze myself out of that little car. I used to drive it in Phoenix on 110 degree days with it 75 degrees inside the car...with R134a.

They just don't work well at idle or if your windows are not tinted. The large interior volume of a Jeep doesn't help.

[Beach_Dude]

I got my 609 online.

[Texas993]

Holy ing hell!!!! I just woke up and just realised what it might be.

One simple item that is not in a single document, post or anything, that has ever been brought up is the equalization flared fitting.

So, the equalization line is designed to open up the expansion valve on the suction side if pressure is too low, allowing additional freon. Makes sense...

All modern evaporator cores come with a shrader valve built in them, probably for universal systems, regardless of being model specific and that some models that use this coil might not have an equalization tube.

If a valve is installed on the suction side of the evap coil, once a low pressure or vacuum has accumulated, it will always detect a vacuum and excessively open the expansion valve, right?!?!

OMG, did I just figure this out?!?!

Remove the God damn valve from the suction line of the evaporator coil?

Beach_Dude:

Thanks for posting the solution. I was having the exact same problem with my completely new AC system and components. Sure enough, I had the Schrader valve in the evporator too. Removed it, recharged and so far it is perfect!

[Beach_Dude]

Just drove inland to santa Ana, mild heat wave, and it's cool af in the cabin.

So stoked. Just glad we know now!

[Towtruck]

I just finished cleaning/flushing the evaporator, condenser and the lines and getting ready to reinstall after ten years sitting on the shelf. The condenser and evaporator are original factory components...hoses redone for 134 and if I remember correctly, the York compressor was changed to a 134 compatible unit at the same time. Components were pretty clean during the flush...looked like a little old oil, but no solids at all.

I'm thinking maybe I should change the oil in the compressor before I go any further as it's been sitting dormant on the engine for at least ten years...basically acted as an idler pully for the alternator. The hook-up ports were tightly sealed way back when I removed the evaporator for some interior work in the cab. It turns feely by hand, but I don't want to engage the clutch and run it without an oil change. No idea where to find the drain and filler plugs, and don't know where to find the oil capacity value. It's a horizontal installation. Any tips? Any guesstimates as to whether the compressor is going to work after sitting dormant (on the engine) for a decade? How much Freon should I buy? (I have gages and an electric vacuum pump). There are no specific details in my Haynes manual. Thanks.

[wiley-moeracing]

You will have to change the oil and flush the system then fill compressor with the correct oil for r134. You can check the factory service manual for capacities or check online but that's just a starting point( was originally based on r12). You may need to have a professional charge your a/c system, you will need to use the gauges to get it correctly filled which takes experience to understand.

[SJTD]

Yeah. With everything cleaned a flushed you don't want to mess it up now. I'd remove the pump so I could flush it good, both the head and the case to be sure it's got the correct oil. Plugs are on the side of the case.

Oil level on these is set with a dipstick. Check for a book on http://oljeep.com/edge_parts_man.html for how you set the oil level. There ought to be some info on how much extra to add for a new clean system. Even if you can't find a manual for your year I doubt this info changed over the years as.

[SJTD]

My '84 book says the compressor comes charged with 7 ounces of oil. It also says that replacement of the condenser, evaporator, A hose, the drier, or expansion valve requires the addition of one ounce of oil.

I take that to mean if all those components are changed, as in your case, you would add a total of 6 ounces though why any for the expansion valve is required doesn't make sense since it doesn't hold a significant amount.

Also it isn't clear if the 7 ounces the new pump comes with is what it normally runs at but I would guess so.

If you have the original service valves you can front seat the valves, CW, to isolate the pump to check the oil level after running it without loosing the full system charge. Only the gas in the pump will vent. You can then purge the pump.

Capacity is 2-1/4 lbs of R12. Idunno what that equates to in 134.

[Towtruck]

Thanks very much, gents. I wasn't very clear in my post, but this compressor was run with 134 and ester oil for perhaps a year way back when I initially converted it to 134. I'm just thinking an oil change for the compressor would be a good idea since it sat inoperative for a decade (installed on the car, but clutch not engaged).

I really don't want to pull that beech off the engine, especially if it turns out it doesn't work after sitting for so long. So, I'll see if I can pull the bottom plug and drain it (thanks for identifying where the plug(s) are located). If I can't get at the bottom plug, I'll suck the oil out with a syringe gizmo and see how much I get. Thanks for the official specs for oil and Freon quantity. All very helpful. It's currently sitting in the driveway with the radiator and grill removed because I didn't want to install the new accumulator until I had a plan for the compressor....yadda, yadda....chicken egg... I now have a plan. Thanks again.

[SJTD]

I got the impression you weren't sure if the pump hadn't been converted. If it was properly converted and flushed I'd prolly go with it. If not changing the oil would be good since you'd get rid of the oil that might have some residual mineral oil.