Reply to "AC help"

There's no pressure switch in the Pantera A/C system so your compressor cycling on is no indication of state of fill of your system.

I have heard untold stories of Pantera A/C systems being poor or non functional after an R134a switch, but there's a lot more to the change than most folks think;
1. You need to completely flush the system and remove all traces of mineral oil, then use an ester oil.
2. The type of fitting (flare vs. o-ring) or hose is somewhat immaterial, but your hoses need to be in good condition.
3. The evaporator valve under the dash requires changing to an R134a compatible one as the pressure drop across the orifice is different in an R134a system. This is the single biggest mistake people make and the biggest reason people say R134a system isn't working or blows high pressure hoses.
4. You also need a new dryer anytime you have the system apart.
5. You need to add a high/low pressure switch to the system to prevent over pressuring. The simplest ones screw on the fill port after you remove the schrader valve and the new fill port is on the pressure switch.

Nothing wrong with R12, just be sure you have found the leak(s) as it gets expensive really quick if you keep adding to the ozone layer! Have the shop pull a vacuum on the system and leave it at least 30 minutes to see if there is any leak down.

I picked up a dual charge and recovery station from a CA shop going out of that business. It has saved me far more than it cost.

Julian