My AC in my 1989 Laredo is not very cold and with summer approaching I would love to get my ac working finally. I have looked into it a few times and have found nothing that exactly helps me. Do I need a new compressor or just rebuild it with the needed seals? As for the drier what is needed? If someone can provide me with a list of needed parts and maybe even links along with a list of steps, I can do it myself. I want to go r-134a of course, r-12 is too rare now. Maybe if someone knows a shop near me, Riverside California, that is able to do the conversion cheap then I can go that way too.

 

Your AC is a lot more complicated then you think. Unless you are up to replacing every component it would help to narrow down your problem a little more. When was your AC last working? Is the clutch engaging? Does the system still hold pressure? Your major components are the condenser which is in front of the radiator, the compressor/clutch, the dryer, the lines (w/o-rings), the expansion valve and the AC evaporator which is behind the dash in the box with the heater core. I have just started rehabbing my AC in my 96 XJ. I knew it had a little pressure when I bought it in 2022 but it had no pressure lately. I purchased all the lines that remotely looked bad as some are metal and some (most) have a rubber component that had hardened, a new dryer and the expansion valve along with the condenser. I replaced all the o-rings and installed the parts. I then vacuumed down the system using a AC pump and gauges and found that the system held a vacuum which is necessary before you start adding freon. Today, I hope to have the freon introduced and have a working AC. Don't forget that along with each component you replace you will need to add oil back to the system. There are charts on the net that have suggestions to how much to add. You can also drain the oil from each component as it is removed and replace the oil based on that.

I am by no means a AC tech, I am better at maintaining a AC system then installing them, so I am going slow with my AC work. There are a lot of resources on the net that cover AC work, do a search, read up and check your system to see what state of disrepair it is in and then make your decisions, good luck!

 

Have you ever serviced an AC system? Do you have a vacuum pump and manifold gauges?

 

I’ve never done anything to do with ac before, but I am very mechanically inclined. The ac blows air, and it’s not warm or hot, it more or less feels like wind blowing at you, kind of cold but not ice cold like ac should. I believe it holds pressure. I bought the jeep back in 2022 after it sat for years. It only has 94xxx miles on it too, so I find it odd if the freon is low or empty. Maybe I buy a can of r12 off ebay and try filling the compressor with that?

 

Cole, the system will not accept freon unless it is under a vacuum or the compressor is engaged. If it is blowing air like that of outside air, I would think the compressor is NOT running. You can check by opening the hood, have the engine running and having someone turn the AC to the on position with temp in the coldest position and observing the clutch on the compressor. The clutch is on the front face of the compressor, with the engine on and the AC off it is not engaged, (not turning). If the clutch turns when the AC is on, you could add freon. If the system has NOT been converted to R134, do not just add it, changes have to be made before it will work. That is the first thing you will need to read up on is how to convert a R12 system to R134.

 

If the compressor is working, am I not able to fill it with R-12 freon? Or is converting to r-134a the only way?


EDIT
I checked if the compressor was working. I had the Jeep on, AC on. Looked at the compressor (only I was home and had to go back and forth) and saw the pulley was spinning but not the thing on the very front, looks like it had bolts in a triangular shape? Turned AC off and all looked the same. Could the clutch be bad causing the compressor to not run, meaning I could technically have some r-12 in the compressor still?

 

I

Part did not spin, on or off
I uploaded a picture, the part circled did not seem to spin, but the serpentine belt would turn the pulley. Bad clutch=no compressor?

 

That is the clutch. It just means the system probably does have enough freon to overcome the low pressure switch which is attached to the dryer. It can be jumped but I don't think you really want to dump expensive R-12 in a system where it could leak out in 30 minutes! The freon does not get used up, if your system is low then it leaked out somewhere and the usual culprits are the condenser and the evaporator but could be any connection in the system....hoses, connectors, o-rings, expansion tubes (looks like a silver box about the size of a pack of cigarettes located close to the firewall or even the compressor. That is when you are basically looking at replacing the dryer, connectors (which means added adapters or replacing the hoses) all the o-rings and the oil (system flush) to change to r134a so the price of freon doesn't break the bank. Then you have to have a vacuum pump and manifold gauges to remove all the air and moisture and hope you don't have any leaks before you can add that freon. I worked on my AC today, pulled a vacuum and then found it had a leak, tightened connectors and repeated the scenario 3 times and still have a leak and only 2 components left and only 2 connectors left to tighten. I really hate AC work but will do some other things and come back and remove the front header to get to the two fittings on the condenser and vacuum it down and see if it holds. If not I will add a leak detector to the system and see if I can spot the leak that way. If its my evaporator, I will just do without AC...

 

Soooo should I try jumping it or begin swapping everything over to r-134a?


This video shows the steps but it seems very time consuming and I would have to find every necessary part and somehow a vacuum pump…. sounds like almost a job for a shop?

 

If you don't have any experience with auto AC, I would suggest a shop. Some parts like AC hoses are getting hard to find for my 96 model, I would think your 89 will not be any easier. A shop will charge you more, but you are paying for is labor and experience. When they get it back to you it should be good to go.

 

The weird part is the AC is ice cold during the first start up after sitting over night…. ice cold.

 

I agree with Sig220. The hardest part is ensuring that your system is leak free and clean before charging the system regardless of which type. Real R-12 (not just propane labeled as R-12, or the countless "drop-in" subs) is very expensive and can be difficult to source. You'll need a new dryer (at least) and probably a new expansion valve regardless. Of course, this depends on the condition of the rest of the system.

One note about Nick's video. While he does explain many of the steps, note that his AC compressor has been relocated (swap with alternator).

 

I’m in class and got bored so I began googling ways to test if my compressor is shot and came upon “Enviro-Safe Artic Air for R12 Systems” and it’s inly $15.95 a can and says its a direct replacement for R12. I still need to test my compressor because I don’t know if the clutch is activating, which could be because of low pressure right? I could jump a wire from my batteries positive terminal to the compressor while running to briefly test if the clutch engages right?

 

Do not mix coolants. Your system is designed for R12 and will work best with it. Them bandaid cans of coolants that you simply shoot into the system are bad. Sure they may get it cold for a while, but if you got a leak, it will leak again. If air gets in, well air has moisture in it and it will eventually overload the dryer and they you will have moisture freeze up and block passages.
I recommend making sure the mechanical stuff is good first, does the clutch engage without slippage, if the hot coil clear of debris, are the HVAC flapper doors opening correctly (they are vacuum operated and if you got a leak in the system they may not open or close properly)
If all them things is working good, then Id give the system a pressure check, see if any of the R12 coolant has leaked. If it leaked, then the leak needs to be repaired, dryer renewed the system evacuated with a vacuum pump, re-leak checked, then pumped down for a long time to remove all traced of water (water is extremely difficult to pump out of a vacuum system) then recharge with R12 Yes you can still get R12, and it works best in a system designed for R12, it will blow the coldest if you use R12 in an R12 designed system.

But first step is to assure the clutch aint slipping, the hot coil is clear of debris, and the HVAC flapper doors are all working (i.e. the cold door is fully open,, the hot door fully closed when you move the control levers to full AC position Remeber on these early XJs these doors are operated by vacuum from the intake system of the engine,

I hope it is something easy, like the hot (heater) flapper door is staying open, which may explain why she blows cold upon a cold start, before hot antifreeze gets to the heater core. (after the heater core gets hot, then you will be mixing both hot and cold air if the flapper door to the heater is staying open for example)

Good luck

 

Sounds like you are wanting to do "you". Please don't try to jump your compressor/clutch with a hot wire straight from your battery. The proper way to jump a low pressure switch is by jumping the wire going to the switch. Should be two wires in the connector you don't jump the side the pressure switch itself is on, you jump the connector that plugs into it. Just use a paper clip inserted so that contact is made to both while the vehicle is running and the AC is on. Just insert the jumper (paper clip) and if the clutch engages pull the jumper and you have answered your question on the clutch engagement. Actually there are other things like the air gap that come into play but we will leave that alone for now. Might be a good idea to get a manual/owners handbook that shows the fuse box and what circuits they are protecting to make sure that voltage should be available, etc. The inside cover over your breaker/fuse box under the hood should have markings indicating their use. Maybe somebody pulled the breaker on the AC to use elsewhere.