If the center of the compressor is spinning, not the belt driven pully, but the actual clutch in the center of the pully, then it’s functional. Most likely your gauge is faulty.

You might also have it on the wrong port.

 

As has been mentioned you really need a full gauge set to see what's going on. Harbor Freight sells one that's not too expensive and is fine for home use. The low-pressure gauges on those refrigerant cans are garbage. Also, never use refrigerant that has sealer in it. It can really make a mess of things and can damage equipment if you should have the AC system serviced by a shop.

Bear in mind that when you charge refrigerant in what's actually pushing it in is the can pressure being higher than the pressure in the suction side of the AC system. However, as the gas leaves the can guess what happens - it gets cold and the pressure inside drops! This can make it difficult to get refrigerant out of the can. (NEVER turn the can upside down, if you charge in liquid you'll likely destroy the compressor - liquid does not compress!!) I use a hot plate with a coffee can full of water to keep the can warm and keep the pressure inside up. (Hot to the touch but definitely not boiling.)

There really is no "correct" rest pressure (that is, with compressor off). It will vary depending on the system and ambient temperature. However if that can gauge is correct and you really have 200 psi in there at rest it seems grievously overcharged. (Typically I see maybe 70-100 psi at rest.) If that is the case you'll need to have the system evacuated and then charge in the correct amount of refrigerant by weight.

Always charge through the low (suction) side of the AC system. I've seen what happens if you accidentally open the wrong valve, and it's not pretty!

Oh, and PatHenry, thanks for the kind words, but believe me I am not a pro! However I was "trained" by a close friend (now deceased) who was a professional auto AC tech for over 40 years. If I'm fortunate I've managed to pick up maybe 5%-10% of what he knew. He was a good friend who is sorely missed.

A great source of info for air conditioning issues is: https://forum.aircondition.com/

 

Hahaha well Rambler, you have shown that you might have picked up a bit more than you think.

Spencer, if you can see the compressor spinning (as mentioned) you know it's kicking on. Your e-fan wil also kick on.

If you don't see it kick on, you can pull the plug on your receiver/dryer (the little canister on the fender behind the battery with 2 hoses and the sensor connected to it) and jump the plug contacts using a paperclip or wire and the compressor should kick on. Be careful not to let it run for more than the 1 second or so it takes to confirm it kicks on and I would want to be sure there isn't 200 psi of pressure going on on your low side.

Just so you know, I knew nothing about ac until last year, then from help via this forum, got my ac running (right before the weather cooled down, lol) and while it blew cold air when it started getting hot this year, the compressor was noisy and since compressor failure will damage everything else in the system, I replaced the compressor (and receiver/dryer since you should any time you open the system to the outside air and it's a $10 part) -- the hardest part was paying to evac the refrigerant - since I had the gauges and vacuum pump already, it was under 200 total.. 140 for parts and refrigerant and 50 for the evac and it's glorious being able to have ice cold a/c and run it with peace of mind.

 

Don't let this happen. It will certainly ruin the condenser and likely the expansion valve - which is bad.. but what is much, much worse is it will damage or severely compromise the evaporator... and you have to take the whole dash apart to change it (similar to a heater core replacement)...

At best, you'll need the compressor condenser and be paying for a shop to completely flush the system.

If you are planning to replace the compressor in the future, start hitting the mounting bolts at the bottom with PB blaster now.. I broke 2 of the 4 due to rust. Not a huge deal since they are easy to get a drill on, but drilling is never fun. (I drilled and tapped mine)

 

If the compressor fails and locks up it sends shards of metal into the AC system. Parallel flow condensers and evaporators typically used in R134 systems cannot be flushed out, they must be replaced. The reason is that if debris lodges in an area, the flushing compound will just route around it. Then later it can come loose and destroy the new compressor. (The old R12 systems used serpentine condensers and evaporators because that refrigerant was more efficient; those could be successfully flushed.) The lesson is if the compressor is noisy disconnect it or replace it ASAP before it self-destructs! (Overcharging can also cause a noisy compressor.)

 

So not possibly blowing out the evaporator, definitely blowing it out.

I will take drilling some bolts out and a couple hundred bucks over a few hundred and pulling the dash apart every day and twice on Sun.

 

Here's a pressure diagnosis flow chart from Sanden (manufacturer of the XJ's AC compressor) which may be useful:

https://www.sanden.com/objects/SANDE...OSIS_CHART.pdf

 

Thank you for all the info. I was planning on having the compressor replaced, but I can’t afford it until at least the end of the month, so I guess I’ll suffer a while longer. I don’t think I’m equipped to replace it myself, but I’ll spray the bolts so the shop doesn’t break them. Thank you Rambler for the chart.

 

Yeah, you really do not want the compressor seizing up on you, that's a world of hurt and a big mess to clean up. If you're lucky the compressor noise is just due to refrigerant overcharge but until you determine that or replace it your best bet is to leave the AC disconnected.

 

So I guess I should take it somewhere and have them look at it before I buy the compressor, thinking I can probably buy it cheaper than they'd charge but we shall see.