Hope someone can help me with this problem. Have a 96' Dodge Ram PU 1500. A/C blows cold but often will start to warm up after awhile.When the air turns hot, I found the clutch is no longer cycling. Checked low/high side pressures w/gauges (and engine running). Dodge manual said low should have been 30-50, was at 52. High side should have been 200-260, was at 310.Does this mean my system is overcharged, or low on freon? I hooked up a bottle of freon w/a guage on it and meter was in yellow area. Directions indicated not to add freon, seek help. May be overcharged.Systemseems to work good untilit shuts down the clutch. The fan (blows), plenum door (closes properly), clutch (cycles) all seem to work ok. If the system is overpressurized, is it a matter recovering some out of the system to lower it? Which side(s) of the system to I drain. Should high/low side be same pressure when running?

 

Overcharging makes the clutch cut out so you don't damage seals. Drain some from the low pressure side.

 

Have you added any freon lately? It's also possible there is too much oil and not enough r-134a.

 

yes, I used one of those Walmart special cans of freon w/oil in it. I only put about 6 oz. of freon in it to see if it would have any affect. The gauge on thecan was in the yellow zone when I hooked it up. The pressure on the gauge didn't really change when I added the freon. So if I do as you suggest, and drain freon from the low side, should I drain it til the gauge (A/C manifold gauges) reads around 40? Should I see the high side pressure come down into range after this as well? Thanks for any help..

 

UMMM I sure hope your not using Real "Freon" because That was outlawwed in Cars/trucks some years ago. Instead R134a is the replacement since '94. Also a product called Red-tek Is available , and some say it works better. As with ALL A/C charging, and particularly Discharging, An A/C Evacuation /recovery/cleaningMachine is always supposed to be used , Period. Venting to the Atmosphere is not only Very Illegal, but also super Unsafe. Of course Accidents do happen.
Take care
Fork[sm=gears.gif]

 

Tomorrow morning test it first thing at 1 minute intervals with the A/C on Max and the clutch engaged.

 

If you get conflicting readings, you need a better gauge. if it keeps reading high, you need to drain.