Hello,

Someone please provide ac compressor settings on the low and high side for 2002 F250 7.3. When it blows, it blows cold, but then some times shuts off and blows warm air. I can turn it off and back on and it will work for a little while, but seems to get warmer because the compressor seems to turn on and off which seems like an electrical problem. A buddy of mine recharged it a few months ago and it worked fine until yesterday. Is it turning on and off because the freon level is low? Can i fill the low and high side from only the low side hose? Thank you, Tommy

 

Did you check the shim on I believe it is the clutch? This might be your problem. I actually took mine out and it is now blowing cold air again. I think Springerpop is the one with the instructions.

 

I will check - thank you. Do you happen to know the pressure settings for the high and low on the ac? Thank you.

 

Camp250, I don't have a clue about the pressures. I am sure someone might chime in on that one soon.

 

http://www.springerpop.net/F350/air_gap.html

Check this out.

 

FWIW,
I had to replace the fan clutch (engine fan) on my 02 in sig, it was not pulling enough air across the condenser, when the condenser gets warm it would quit cooling, it would work just fine going down the road, but once i would stop moving it would stop cooling, just one more thing thing to check.

 

GREAT SITE AND VERY GOOD INSTRUCTIONS!!!!!

JERRYJUST

 

Pressures are relevent to out side temps. Your low side switch shuts the compressor off at around 23 psi. Low freon wants to suck that side into a vacuum. But yesterday at 105 degrees I had a truck pulling low side at 30 psi and high side at 210 psi with the engine fan engaged.

 

Great - thank you! What if i have too much pressure currently (low side is about 45 at 100 degrees yesterday) High side is about 150. How do i release pressure? Thank you.

 

do the shim fix.. it fixed my a/c! so easy.

 

I just pulled it out and replaced it with a thinner shim. I used the thinest shim I could find and it wasn't much different than the original shim. Is working for now. I am hoping there was not another shim inside on the shaft. If it warms up again, i will pull over and pop the hood and see if the compressor is turning. You guys were correct, very easy fix!! thank you!!

 

You might even be able to remove the shim completely, which is what I just did with mine yesterday. What you want is an air gap of about 0.010" - 0.020" between the clutch plate and the pulley surface.

You can go as close as possible as long as the clutch is not always engaged, but to determine that gap spacing, you need to measure/set it on the coldest day of the year for wherever you'll be driving during the winter season so that you don't end up with complete contact at a time when you're not needing the A/C.

 

I will if this doesn't work. Thank you.

 

Use this chart
R134a Refrigerant Pressure Temperature Calculator

If the pressures are a little high. But the system is cooling and you are ok with it. Leave it alone. If it is blowing warm then you have to start looking for the problem.

 

Can someone post the link for the shim mod mentioned earlier, and what the advantages of doing it are???? Thanks