A/C on my truck not working, any help?

[tri5ron]

I've got a '97 c 3500 CC dually 7.4 litre, (454).
The A/C compressor was replaced only 2 years ago.

I turn on the A/C switch now, and the compressor clutch engages for 2 or 3 seconds, then dis-engages for 6 or 7 seconds, then engages for 2 or 3 seconds again.

this cycle keeps repeteing itself for as long as the A/C switch is on, and it never blows cold air.

The fan is working, the air is blowing, it just never gets cold.

anybody have experience with this?

[wvspeedfreak]

It is just low on refrigerant.Charge it up.

[ridered11]

^what he said


and don't run it on low, you'll burn up the compressor.

[tri5ron]

I haven't had the refidgerant level checked yet, so I'm not sure if it is low. It was working fine one morning, blowing about 40 degrees, then later in the afternoon it would not blow any cold air at all.

I am going to have it looked at, but with it cycling on and off, I thought it might be some sort of signal to the compressor issue.

it's almost like it gets turned off, then on, then off again. judging from the wy that it engages, and disengages on a regular 2 second/6 second cycle.

[wvspeedfreak]

The low pressure cut-out switch (or clutch cycling switch) is what is turning the compressor on and off.It is because it is low on refrigerant.Charge it up.

[tri5ron]

Cool! THANKS!
I'll try to get it charged tommorow, and will report back any findings.

Ride hard, Ride safe, and keep the rubber side down.
Ron

[BakerRacing40]

Originally posted by wvspeedfreak
The low pressure cut-out switch (or clutch cycling switch) is what is turning the compressor on and off.It is because it is low on refrigerant.Charge it up.

basically your looking at low refrigerant, low pressure switch, or high pressure switch. you might have a leak at a fitting possibly around the compressor since it had been replaced before, if improper o-rings were used the refrigerant will eat away at the o-rings till it leaks. look for a oily residue at the connections and the front seal on the compressor. when you replaced the compressor did you replace the dryer or the orifice tube?

[FreekShow]

i really dont know if this has much to do with it but my heater blower was doing the same exact thing. turned out that the whole blower motor was bad.