1996 Lincoln Town Car compresser starts and stops

Hi champion2165. Welcome to the forum. If I understand correctly, performance has improved after you added some refrigerant, but not enough. First of all, look on the top of the receiver / drier to see if you have a small round sight glass. Only Chryslers and some Fords use them, but on Fords they aren't real accurate. Without a sight glass, it is impossible to know exactly how much charge there is in the system. On Chryslers, there will be no vapor bubles visible when the system is full. On Fords, there will still be some bubbles so don't keep adding refrigerant in an attempt to eliminate them. Lots of bubbles, or a foamy appearance means you need more refrigerant.

If you don't normally wear safety glasses, now's a good time to start. Many professinals wear face shields. Vaporizing refrigerant can freeze eyeballs and cause frostbite. Just wanted to mention that in case you weren't already aware of the dangers.

Also, it may be normal for the compressor to cycle on and off. Most older systems regulate the evaporator temperature that way so they don't get too cold. That would result in the condensation freezing into a block of ice and blocking air flow. Use a small thermometer in one of the duct outlets. If it hits 50 degrees or less, it should be fine. The real comfort comes from removing the humidity from the air.

Caradiodoc