1979 A/C clutch toggles off and on is that normal?

[Gary V.]

The A/C clutch toggles off and on, the A/C blows cold. I'm not sure if that is a sign of low freon or not. With this year 1979 should the compressor always be on when the A/C setting is on Max or Normal cool?

[Edward J.]

Re: 1979 A/C clutch toggles off and on is that normal?

Gary generally that a sign of low freon. It is normal for some cycling of the compressor, you should have a pressure gage installed so you can watch at what pressure the A/C clutch is cycling at. frequent cycling is low refegeriant.

[Jim T.]

Re: 1979 A/C clutch toggles off and on is that normal?

If you 1979 has a sight glass at the top of the dryer and you see lots of bubbles viewing the sight glass, this normally means the air conditioning system is low on R12. My 1970 has the sight glass equipped dryer I am not familiar with 1979.

[Edward J.]

Re: 1979 A/C clutch toggles off and on is that normal?

Jim, I don't believe they had a site glass on 79. its just a aluminum canister on that year.

[Gary V.]

Re: 1979 A/C clutch toggles off and on is that normal?

Thanks for the replies, It does not have a site glass and the A/C clutch is not rapid cycling. I read the shop manual and I'm trying to understand what their talking about. I will try to get a gauge on there and see at what pressure the clutch disengages at.

[Edward J.]

Re: 1979 A/C clutch toggles off and on is that normal?

Gary, I don't know what your outside temp is, But the colder it is the more it will cycle. In general it really not a good time of the year to check the a/c operation and its performance, unless your in a warm climate like Fla.

[Bob E.]

Re: 1979 A/C clutch toggles off and on is that normal?

I believe the '79 Corvette uses a CCOT, cycling clutch orifice tube, A/C system. The A/C compressor
cycles off and on in normal operation.

[Gary V.]

Re: 1979 A/C clutch toggles off and on is that normal?

Thanks Bob, It does have the CCOT system. I see the acronym in the service manual but never the explanation of the letters. I live in Florida and the A/C compressor seemed to be on all the time in summer. With a little cooler weather it's probably normal to cycle. If it ever gets to the point of rapid cycling, I'll know the freon is low.