Using Long Term Shelved AC Components

[XCRN]

I am now ready to get AC back in my Jeep since the LS swap and will be using some of the factory components like condenser, evaporator and one of the hard-lines but will be getting a new dryer and compressor. They have been sitting open to the elements for like 2 years now and was wondering if there is a need to replace anything on them like O-rings or special kind of cleaning procedure?

I just would like to try and save the money since most of these components are newer and some are even Mopar.

 

[freedom_in_4low]

I don't really have any advice on what to do but I can tell you what happens if you have anything in there like water or any oily substance that is slow to evaporate...when you go to evacuate it, the pressure will stay up for a very, very long time (making it look like you have a leak) waiting for whatever is in there to completely evaporate.

The passages in the evaporator and condenser are very small and clog prone and any debris that makes it out of them may clog something else (isn't there a strainer upstream of the orifice?). My inclination would be to flush and back flush with something like acetone that completely evaporates without a residue but that's probably not good for the o-rings.

The best thing would have been to cap them when put in storage but that ship has sailed. We cap ours just to wheel them over to another building on a cart, and anything that's going to ship loose or sit for a while gets the connections spun closed and pressurized with nitrogen to make sure nothing gets in.

 

[sab]

Assuming that the system worked before the LS swap, I don't know that I'd necessarily replace anything other than the dryer (it definitely needs to be replaced due to it absorbing two years worth of humidity.) If, however, the system didn't work due to compressor failure, in addition to the compressor, I'd replace the condenser and the expansion valve (or orifice tube, I'm not sure which one our TJs use) due to debris that is hard to flush from those two components (the condenser tubes became smaller when R-12 was phased out - with R-12, you could flush the condensers pretty well.)

1. Assuming you never drained any PAG oil from the components, drain as much oil from each component as you can, but measure how much oil came out of each because you need to put the same amount back into each one. I haven't worked on the A/C system for my LJ, yet (fingers crossed), but for the cars I've done A/C work on, the factory service manual typically gives oil volumes for components when replacing them. Use that if you already lost the oil.
2. Get a flushing kit, which should contain a flushing bottle with air nozzle and some fluid. Flush each component per the instructions.
3. Get new o-rings and replace all of them.
4. Get new valve cores for the pressure and suction connections and install them (you'll need a tool for that.)
5. Using the correct PAG oil, put the right amount into each component. If you replace the compressor, be sure to check if the manufacture already installed oil (many times, they do) so that you don't overfill it.
6. Install everything.
7. Charge system. If this is a custom system (due to the LS swap), and you've changed the system volume, you won't be able to go by the hood sticker for determining how much refrigerant to add. You'll have to go by pressures. If that is the case, take it to an A/C expert so you don't over- or under-charge it.