Since I bought my XJ12 a few months ago, the A/C hasn't worked. I did charge the system up once, just to make sure the Compressor Clutch and the Pressure Switch was okay, and that the Compressor was actually creating suction and pressure.

After turning the car off, I had a hissing and the next day the refrigerant level was so low the clutch wouldn't kick on.

I brought the car to my Jag mechanic for the first time a little while after, and saw there were some hidden undercarriage problems that I needed to sort out. First was that the radiator mount bushes were all missing, and the lower (and upper, as it turns out) condenser bushes were missing too. The engine oil cooler, mounted right behind the spoiler grille had it's mounting pins sheared back after someone got too close to a curb.

I figured the leak was from the condenser smashing itself to bits against the radiator because there was nothing keeping it in one place. For the XJ12, that's about $300. I replaced the radiator and condenser bushes already.

I decided to pull the grille off today and take a look for myself at the hoses and condenser coils. I charged the system up, and sprayed everything I could see with some soapy water. No bubbles at all. I turned the car off and couldn't hear any hisses from the condenser area. I checked under the hood, and heard a very faint hiss, quieter than I remembered it last time.


So, I've got my fingers crossed that the only leak is right there, at the low-side service port. I'm going to the dealer tomorrow to order the Low-side and High-side ports and O-rings, and maybe a new Receiver/Drier/O-rings depending on the price.

Then it's a matter of waiting for the system to eventually discharge, pull a vacuum on it, recharge, and hope that by Summer I still have working A/C.

-Nick

 

Had this same problem on my x300 on both the high and low side ports. I bought it about 6 months ago and it was blowing cold for about 5 months. I don't know when the leaking valves occured and I didn't put refridgerant into the system until after I fixed it so I cant attest to how long it took the refridgerant to leak out. I replaced the hoses with 2 uro hoses I found on rock auto that had schrader valves so I wouldnt have to replace the whole hose if it leaks through the valves again. Also changed the receiver dryer.

 

I wish aftermarket replacements were available for my XJ12, but due to no demand, I'd have to stick to OEM hoses from the dealer at over $400 for the pair of suction/discharge hoses. I'm glad to see that the valves are separately available.

We'll see

Nick