NOS Motorcraft AC pump, can I run R134A?

[69dieselfreak]

Geesh, all I do is recharge my R12 system with 134A every spring and it's ice cold all summer. I didn't change anything but to install the R134A fittings....My system leaks out in the winter (atleast it did last year) but I found an o-ring out of place this spring so it might hold fine this winter....Nice and cold all summer...Maybe not ideal for you southerner's but for my 30C hot day's it works great......I don't reduce my charge level either like they tell you to. I put in 2lbs-12oz.

same here thats all i did when i did the conversion on my rig
by the way a/c flush is very expensive we use rubbing alchol i think is 90 some odd % to flush our freightshaker a/c systems and its cheap and works great

 

[6 Nebraska IDIs]

Thanks for all the help guys!
Im going to do everything I feel comfortable with doing at this point. It just sounds like some of it is very complicated and technical, like installing that valve thing, and adjusting that screw to an exact psi. I dont have a vacuum system so I'll have to take it in anyway.

 

[typ4]

installing the orifice valve is easy ,IF the old one comes out in one piece. If not they make a repair tube than compressions on to the cut off piece. I have one and it works, I also have a condensor that is an upgrade for 134 in the older trucks, I have a nice cold system that never leaks, new seals and old hoses junkyard compressor, got lucky.
Oh and the correct way is to charge a system by gauges and the chart for the ambient temp, and the cheesy little gauge on the refill kit is pretty damn close

 

[Mr_Roboto]

You are supposed to undercharge the system because R134a runs at higher pressures than R12. Since most R12 systems cycle based on low side pressure, the result is higher high side pressure (and higher compressor head pressure) than the system was designed for.

R134a systems have a high side switch to cut off the compressor if the pressures get too high. This switch is "supposed" to be added when an R12 system is retrofitted.

 

[RLDSL]

You are supposed to undercharge the system because R134a runs at higher pressures than R12. Since most R12 systems cycle based on low side pressure, the result is higher high side pressure (and higher compressor head pressure) than the system was designed for.
trofitted.

there's an easy way to add one of those switches here you just screw the thing on and run the wire for the ac clutch through the switch