Need A/C help. No idea where to start.

[dangun486]

Well I've been putting it off for awhile, but I finally want to start tackling this project. Two years ago I got my uncle's 92 explorer when he bought a truck. He had it for two or three years before that. The a/c doesn't work (it never worked when he had it) and I'd really like to get it working again (90-105 the past two summers with no air hasn't been fun).

Now here's my trouble. I don't know where to start, especially since I don't know what the original problem was. I don't know if it was a leak or a part failure. So I'm reaching out and hopefully someone with more experience can give me some advice. Where do I start?

Also should I focus on fixing the system as is (again it's a 92 so it had R-12 refrigerant) or do I make the conversion to R-134a? If it was a leak I'm sure there isn't any remaining refrigerant after 5 year (at least).

 

[ranger7ltr]

This is not a unique situation actually...

I know I have bought used vehicles with a/c issues and brought them back to life...
First I would determine how much of the work you can do and what you will need to farm out to an a/c shop...Then you need to decide which refrigerant to use...And start off with the correct selection of tools to do the job right... Proper gauge set, wrenches to fit the fittings, refrigerant o-rings, oring lubricant, vacuum pump access[rental tool], and refrigerant to recharge the system.

To start I would replace the hoses or have them rebuilt...Eliminates a leak possibility...Most a/c hose rebuilders will use hose that is compatible with R-134A so even if you go with R12 you will be good...

Pull the orifice tube...Look for any debris or black/gray residue on it...If you find flakes of metal or bits of teflon that came from the compressor...Not good but not terminal...If you find gray/black residue that looks like tar then this rebuild just got more involved...The tar like substance also came from the compressor but it is melted teflon and or aluminum and this will have spread throughout the condensor...And you cannot flush this crap out of the condensor...Many have tried and all fail to remove it all...

While the hoses are being done, rotate the compressor and see if the suction side sucks and the discharge blows...If the rotation feels rough or binds up, replace or rebuild it...If the compressor has leaks around the body you can get an oring reseal kit for the Ford compressor for about $25...Or the rebuilt/reman/good used unit market can supply a unit...

Then pressure test the evaporator...On a first gen Explorer replacing a leaking evaporator is pretty easy...If it holds air then you will need to see if the system holds vacuum when it is all reconnected...

Replace the accumulator...It absorbs moisture in the refrigerant system...Every accumulator I have bought in the last 10 years is usable with both R12 and R134a...

Since the truck came with R12 and it is not readily available anymore you might choose to go with R134A...Ideally a later model condensor will help in removing the latent heat from the refrigerant and give you better performance in the cooling of your truck...

So worse case scenario you replace the condensor, rebuilt hoses, new accumulator, new orifice tube, and rebuild or replace the compressor...Use green o-rings throughout and the proper refrigerant oil in the system before all connections are made...Personally I use a synthetic oil that is compatible with any refrigerant so I put in the correct amount, connect everything, put my vacuum pump on and draw a long deep vacuum on the system...

I close the valves and turn the pump off and see if the vacuum holds at 30 in./hg for 30- 60 mins...If it does and the vacuum was being pulled on the system for at least an hour, I would charge with the refrigerant of choice to the proper level...

I think I covered everything to get the system up and running...When the parts and pieces are present the work should take part of a day or so if you do all of it... A shop may make you wait for an appointment though...