At 08:52 PM 7/2/96 -0400, you wrote:
>I've been reading the archives and goofing around with the climate control
>to educate myself as to how the thing works. As of yet, I still appear to
>be an A/C moron.
>When I start the car and turn on the A/C on LO, the compressor will kick in
>and the air temperature exiting the vents will begin to drop. This only
>lasts a couple of minutes and then the compressor kicks out. Then, no cold
>air for anywhere from 10 to 20 minutes, followed by the compressor finally
>kicking in. The air gets cold (not real frosty - I suspect my charge is a
>bit low) and the cabin will cool down nicely after another 10 minutes.
>Sometimes the compressor doesn't kick in at first, but waits for 10 or 20
>min, and sometimes when the compressor does finally kick in it stays on
>(usually) while other times it is on and off intermittently.
Try idling in your driveway, temp set to LO, fan on FULL. If you are
marginally low on R-12, you will probably run continuously.
Next run the fan in LOW, temp on LO, see if it cuts off. If it does
then you have problems with the FREEZE THERMISTOR forcing the system
to cut off. That's the one epoxied on the top of the evaporator
sheet metal. Bentley gives approx. resistance values at different
temperatures, see how it compares.
My observation is that when you are marginal on Freon. the time taken
for the clutch to drop out VARIES WITH ENGINE SPEED, while the time
( resting time ) until it comes back on again, is somewhat consistant.