I know it's January, but I wonder if I can get some advice on this.
I just purchased my first Rx-7 on Monday of this week. It's a 1985 GS. It was a relatively warm day so I thought I could test the a/c as well. When I pushed the a/c button (with the fan on and the selector in "vent" position) the light went on but I did not feel the expected drain on power. Tried it at idle and the rpms didn't even dip. Am I experiencing an electrical problem or maybe if there is no freon then there is no resistance in the compressor? Just guessing. Any ideas?

 

If the compressor works you should see it magnetically couple with the pulley. It should be kicking in/out if working correctly. May be the wire that tells it to couple - could be unplugged or severed. Its actually been so long since I have seen the AC system working on a 7 that I cant remember how its set up.

Most likely if the freon leaked out then the compressor took a dive with no lubrication to it. If compressor died, then little pieces may be in the AC lines.

ALso (again cant remember which type) if it is an orifice tube system, the orficie tube needs replaced if/when you change to compressor. Really your best bet is to take needed hardware to a shop and have them hook up the vac pump to it and check for leaks. Should also replace all the orings while you are in there. It should really cost that much money unless you have to reaplce the condenser or evaporator or any of the lines.

If its the Expansion Valve type system then you may simply have a bad valve.

 

what is this A\C you speak of??? no IanS is right it sould couple with the pully. easy way is just pop ur hood get out and check to see if its spinning if not u could have a bad ground or what IanS said a severed wire. check the wiring and clean it after that make sure there is a belt on it or make sure the compressor is there lol. post back with details.

 

there is a low pressure switch on the low side of the system. dissconect the switch and jump it out with a wire while the system is turned on. the compressor should come on if there is nothing wrong with the system. this means that there is not enough freon in the system. probably all thats wrong with it.

 

A compressor can spin but it doesnt mean its circulating, which is the other half of what it does - Circulates AND raises temperature and pressure.

 

+1 Test the electrical first. If that is ok, then take it to someone for the vacume leak test.