AC woes

Aight...I've been fighting my AC in the XJ since I got it. It's a 98. When I bought it, the dealer told me it had a bad evaporator, and I talked him into throwing a good one in with the deal. Anywho, I quickly realized that the dash was a PITA to R&R, so I decided to try some of the freon with sealer (super slow leak...months to lose charge). I put a can in and got the pressure up to 25psi. Worked great, would freeze you out. After a month and a half, it lost enough that the compressor started cycling, so I went out and got a few more cans. Put one in, and that got it up to around 30psi. Put the other in, and it got up to around 40. It was blowing super cold with no more cycling. I shut it down, and finished up with my other business. Around an hour later, I was ready to hit the road again, and as I pulled away it sounded like a pissed off gerbil and a rattler had a love child and it was under my hood. I pulled right over, popped the hood to find out what the noise was, and sure enough, the compressor was cycling again, but now every time it would cycle it would make that noise. Imagine a cell phone on vibrate...now make it louder. Sounded worse from the interior then under the hood. So I shut the AC off and drove the 8 hours back home. Around town, I decided I'd just let it go to see if it would quit the noise, or get better. It didn't, so I shut it down after a few minutes. When I popped the hood later, I had dyed freon all over the place under the hood. Pretty sure I know which line it's from. What's the deal? Did the sealer stuff react with the straight freon and clog a line? I'm really not able to pay the $800+ the stealership want's to charge for the evaporator, and I just don't have the time to replace it, and now add a line on top of that. Anyone want to tell me what went wrong here? I've worked around my share of AC systems, but never heard anything like that.

Sounds like you might have overcharged the system and the system blew it off due to high pressures? AC systems only require a pound or two or refrigerant in them, and depending on the size of the cans you put in, there might have been too much in there, with the two cans of refrigerant, the dye stuff and whatever air or other contaminants there might be in it.

Possible, but I thought it went off pressure? If there was other junk in there, then wouldn't the pressure be way high before it'd blow lines? There is no visibly blown lines, just lots of wetness.

I should have been clearer. I didn't mean blowing lines, when I said "blowing it off" I was referring to a pressure relief valve 'blowing off' dangerously high pressures within the system. Sorry for the confusion.

Nevermind all of my babbling up there about a relief valve. I was just informed by my roommate that there isn't such a thing anymore, that if the pressure gets too high, the PCM just stops cycling the compressor. Sorry for the confusion.

The 98's are known for crummy evaps, same with the ZJ's, I've known alot of people who have bad ones. I need to replace mine, the leak has gotten bad enough that the one or two cans a year I used to use no longer suffice. One small can lasts about a day or two so I don't use my A/C. Going to get it done this winter sometime or maybe the fall. Shop around, our jeep dealer quoted me $660 for the complete job. I just don't want to pull the dash out myself to do it.