Anyone know where I will locate it? My dad's truck is not taking freon. It has compressor cycling. No cold. Is it the orifice tube being clogged or the solenoid valve at the filler causing this? Pressure on the gauge goes from near 100 with compressor running to 70 while off....
Thanks in advance...
Brent

 

In order to get a reading like that, you'd have to be connected to the high side, not the low side.

The low side pressure should DROP when the compressor engages and should RISE when the clutch disengages. The high side should exhibit opposite behavior.

The valve to the refrigerant supply must be closed when taking measurements.


The ports are supposed to be idiot-proof, however, evolution happens. I'd suggest stopping whatever you're doing, you might just turn that can of refrigerant into a personal IED....

While it is unlikely related to your symptom, the orifice tube is mounted in the evaporator inlet hose. It is not causing your reported issues.

Steve

 

Okay, I told pops that possibly a valve was not opening. The "idiot proof" nipple I used was on the passenger side near the firewall. There was a solenoid directly under the port. So what causes would result in a cycling system with 75 or so pounds static (engine off) pressure?
Brent

 

Look, if you do not have a manifold gauge set and know how to use it, then you really shouldn't touch the AC system. It is far to easy to damage the system and or make the problems worse.

 

A short-cycling compressor with 75 psi static pressure may be under-charged, however, the ambient temperature has to be provided along with the pressure reading in order to properly evaluate the system's condition.

A manifold set is highly recommended in order to properly service the system.

Steve

 

I don't know much about the A/C systems on rangers newer than my 88.. but my neighbor had a similar problem on a 2004 cavalier..it got wrecked and he rebuilt the front end.. he installed a new A/C condenser, vacuumed it, charged it and it would not get cold..and had high pressure in the 70-80-100 PSI range on the low side.. the pressure pretty much stayed the same with the compressor on or off. I helped him tear it down and found out that he did not reinstall the orifice tube when he installed the condenser..we put in a new one, vacuumed it, charged it and it blows ice cold now. just some food for thought...