Ford Repair: Lincoln TC A/C, lincoln town car, r12 freon

Question
I own a 1987 Lincoln Town Car and i was getting ready to use the Air Conditioning for the first time this season and first thing the AC didn't work (keeping in mind that it worked last year). I assume this problem can be easily fixed with a little R12 Freon. But the problem I am having is that when I turn the AC on it seems to put an excessive drag on the engine. I was driving 60 MPH with cruise control and I felt as though my car was speeding up and slowing down. Please help me to understand why this is. Thanx. John

Answer
Hello and thanks for the question...I'll try to help.
 It seems that the cause of the engien RPMs moving up and down are caused by the AC clutch engaging and dis-engaging. If this is happening frequently, you will most likely need a charge of R-12 and also repair the leak. The AC systems are sealed, and should not leak.
Hope this helps,
Erik