i have a 96 contour, V-6, the underhood wiring must have started to give me troubles as the wires to the high pressure cut off switch were frayed and must have crossed over and it was bypassing the switch so the pressure was just going up, up and away.. one afternoon my daughter came home with the car and told me the AC does not cool any more.. sure enough i go out there and see the high pressure service valve leaking some oil.... (not much, but you could see what looked like enough oil to grease your thumb with...
i also did not know how to take the high pressure valve off or was it also a part of the line(its not part of the line).. went to alot of auto parts places, had to go to the dealer and they had to order it..... i tried just about every wrench and socket i have(i got alot of tools, 30 yrs. of buying them, and could not find anything to fit the high pressure valve without messing it up.. i finally gave up and used a small plumbers pipe wrench as i finally got the valve from the dealer($20) and it came with an O-ring on the end)... i then went to auto zone and bought two cans of
R-134-A for about $6.00 a can and a $19.95 hose with one gauge on it to service the cans of refrigerant as i had only the old R-12 gagues and they dont fit... When i took the hight pressure valve off the R-134 already leaked out.. so there was no high pressure coming out and no more oil leaking out... so i figured i dont have to add any oil...
i put my little finger onto the oily assembly when taking the old valve off and oiled the new valve in the O-ring area. I then used an adjustable open end wrench(crescent wrench) to install the new service valve)..... i then attached the can of refrigerant to the hose and attached the hose... i then started to put some refrigerant into the system via the Low pressure valve side(it by the battery side of the car)... i then pushed on the high pressure valve to relase some refrigerant out so it could blow any air/moisture out of the system. it worked(i have no vacuum pump for a R-134 system, just an old R-12 system that i made from an old refrigerator compressor many years ago...
I put 2 cans of R-134 in the a/c system and that was about 3 months ago and its still cold and no problems...
i seperated the wires that were hitting on the high pressure cut off switch and used some Liquid Tape to coat them.... I had to hold the hose/pipe on the high pressure side with one had and use the pipe wrench with the other hand as i was afraid that it looked like it would take the pipe with it and ruin the rest of the assembly, If you have a friend with you have them hold the pipe area with two hands so it does not move and then you can put some pressure on the valve to get it undone....i think i took about 10 lbs of pressure(Torque to get it to move at the very most).. i was afraid i was gonna have to replace the whole hose at first, just take your time and think it out..
the New valve you got might not be the correct one... the corner parts places are selling the add on valves that you put on an old R 12 system and it screws right on the old R-12 valve... if this is what you have bring it back.. the one i got from the dealer had male threads(it goes into the fitting on the hose).......
if you need any more help.. give me your email and i will see if i can find the old valve and take a pic. with the dig. camera and send it to you...
hope this helps.