A/C questions regarding a ranger

[deviant mercury]

Bought my daughter a '94 ranger..nice truck, low mil 4x4 new paint..even has the A/C dealer retro fitted to the newer style-so I can use the stuff to recharge from my local shop myself...."just needs a charge'" uumm hmm. Charged it today and the compressor came on then off then on but started to blow some nice clod air. Then I hear pressure releasing ...looked and see everything going out the pressure relief valve on top of the compressor. Thought well maybe it had a charge and the low pressure switch is bad. I jumper'ed the switch and the compressor did come back on and stay on as long as the jumper wire was connected...after a minute pressure started coming out of the relief valve again and no more cold air...suggestions? I only paid 2200 for the truck so want to stay cheap! taking it in won't be I am sure...

 

[masospaghetti]

Yeah the whole "just needs a charge" thing is complete bullsh*t, there's a reason the original charge was gone - refrigerant doesn't get "used up" by itself.

You need to get a manifold gauge set so you can see the pressures inside the system, otherwise it's difficult to tell what's going on. Could be a blocked orifice tube that would cause an overpressure valve to open.