Originally Posted by Liquidswords32
I added some yesterday and my gauge was reading past 50 psi (just before the warning section)... the temp outside was like 30 degrees. everything seemed fine. I even checked the gauge with the truck off to and it gave me the same reading. I notice when I have the gauge on it the psi's fluctuate back and forth as the compressor goes on and on, sometimes even going below 20psi (low) and then back up eventually just past 50. when the gauge fluctuates does this mean it's going through its cycle? also when it goes back 20 psi's for moment then when the compressor comes back on does that mean it's satisfied?
The reading that counts is the one while the compressor is engaged. Given your current outside air temp averaging in the 40s you’ll want the low side pressure to read between 25-30 psi
In order to accomplish this you'll need to temporally by-pass the low pressure cut off switch (cycling switch). You can do this by removing the electrical connector at the accumulator and inserting a wire jumper in the connector. This will allow the compressor to stay engaged.
Now read the gauge. If its below 25 psi you’ll need to add more. To do this hold the can in the horizontal position. Using both hands to help keep the can warm, open the valve and slowly rock and tip the can side to side so your adding liquid when the can is tipped towards the gauge side.
Once it gets in the range of 25-30 psi close off the valve and let it run for a few minutes. If the gauge goes back down, open the valve and add some more until it stays steady.
Turn of the engine, remove the jumper wire and reconnect the cycling switch. Start up the truck and see if it works normally now.