New A/C problem

[icanfixall]

The orfice tube is either the wrong one or its plugged up with stuff. Really can't be anything else. Hitting 425 on the high side is way too high and very dangerous. Look at some utube viedos or goggle theis. I sure hope your wearing a full face sheild to protect your eyes. A blown up system is sure way to blind you but good. Freon is very dangerous if misused. If the low side drops to zero thats telling me the orfice tube is not functong as designed. Others will chime is and add some help but please be careful around this pressurized system. they take no prisoners....

 

[FoMoCo]

It is working now, the compressor will now stay on until it hits the high switch at 425, but at least it is working. I think adding the oil to the drier was the problem. Once the oil cleared out it is working. The weird thing is I did not change anything, I was going to get some readings and it just stayed on. I ordered a fan clutch and should get installed by next weekend. Once I get the air flow I can adjust the high side. I do have one electric fan that kicks on when the A/c is on, but it is not enough. I had 2 electric fans, but someone on this forum said that you don't the air from the electric fan flowing air in front of the fan clutch for some reason, so I only installed the 1 fan.

 

[stumpjumper3]

Personally if it was me, i wouldn't feel comfortable about that high side pressure. Most of the A/C systems i have worked on have always cooled best with about 175-200psi high side on a 70-80* day and the low side should pull down to about 10-15psi. Now i'm most certainly no expert, but this is how i've charged several systems on some of our equipment when i could not get the info on what sytem capacity is. I also charge from a 40lb 134a keg and gauges so it speeds things up. You are really pushing the limits of your A/C system i feel with that pressure. I would follow icanfixall's advice and check for obstruction at the orifice tube. I would also start fresh. Go down to carquest and get some of their fast flush for A/C systems and individually flush each main component minus compressor, and flush all your lines, then replace all your o-rings because it sounds like you leaked freon quickly. How are you pulling vacuum? How much vacuum? When you shut off your vacuum does the system hold it or come back up, indicating a leak? Need at least 20in of vac for 30-45 minutes then charge. I'm rambling now but i hope some of this helps, but i'm sure there are others who can be more helpful.

 

[tinker927]

when you put new compressor on did you flush your old lines with A/C flush first before you installed your new parts?

 

[MIDNIGHT RIDER]

I think adding the oil to the drier was the problem. Once the oil cleared out it is working.

I am far from even being remotely knowledgable about A/C systems; however, my research told me to use 8-oz PAG-46 (1985 factory-A/C) and to split it between all the components; a couple ounces poured in the evaporator, condenser, accumulator, and compressor intake-line, thus balancing the oil throughout the system.


Also, myself, I would not waste any time, money, or effort on any clutched fan, especially on an A/C equipped vehicle.

Either pin your old clutch solid, swap on a direct-drive hub, or best is two big electric pullers and two pushers.

That is what I would do; y'all can do however.

 

[FoMoCo]

Thanks for the help, I will install the new fan clutch and see what the pressures look like. I would hate to flush everything again, but if I need to I will get the stuff from carquest. FTI stumpjumper, when it hits 70 degrees downs here we have the heater on and wearing heavy jackets, also eating caldo. I think it will be OK since it took awhile before the high pressure got that high and the truck was not moving and it was a 100 degrees outside and humid.

I pulled vac down to 23 and did so for several minutes, I had a leak at the quick connector and had to go get new 0-rings to fix, and I pulled vac several more times, I did not pull vacuum for 30 minutes, more like 5 minutes, but the system was cleaned with thinner and blown out with compressed air.

Back before I changed the clogged condenser the high pressures would hit 425 all the time, the high pressure switch is just doing its job.