A/C Unit Wont Disengage

[fiveoneoh]

Hello All,

My 72 510 wagon's ac unit is recharged as of recently and now im running into some problems with it. Since the AC unit wont disengage its leeching my hp badly. Its also making the engine run much hotter than it should. 

 

Do you guys have any similar experiences or suggestions? 

 

NOTE: I unplugged the control wire (Not sure if thats the technical term for it) from the A/C while the car was running (AC also in off position from the dash) and the problem continued to persist. 

[MikeRL411]

Sounds like a stuck AC clutch unit.  Hopefully your AC is on an individual belt, so remove the belt until you can get the wagon back to the service station that did the work.  Might have some warranty protection?

[LenRobertson]

What type of AC compressor do you have? The old box-shape York piston type or maybe a large rotary? With those the center part of the clutch should stop turning if there is no electrical power to the clutch (AC switch OFF or wire to the clutch unplugged). I believe with the engine turned off you should be able to rotate the center part of the clutch by hand. There will be some resistance to turning if you have a good charge of coolant in the system. If there is no electrical power to the clutch and the center turns when the engine is running, the clutch is dragging and needs replacing. These can be replaced without removing the compressor or losing the AC charge. There is something I'm vaguely remembering about too much coolant in the system causing clutch problems, but maybe that is one of those false memories I keep having.

 

However, there is the newer small style rotary compressors which I know little about. Somehow I got the idea those type of compressor clutches turn all the time the engine is running.  They don't kick out like the older style clutches. I'm sure someone will correct me on that one if I'm wrong.

 

If you can post a pic of your compressor it would be good.

 

Len