Ac Compressor question

G

Greenmachine86

New member
Ok so this weekend i tackled the heater core replacement... so i went back together with everything, tried filling the ac back with freon, no luck. So took to a mechanic friend, they pulled it down, filled back with what i need. So i got in cranked, tried the ac, it started to like surge, and pullin the motor down. Turned off, runs fine... i watched the clutch assembly, and it was like grabbing. Any ideas, thoughts?
 
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The AC will turn off if there isnt proper pressure in the system. Theres a switch on one of the lines over the passenger fender, near the connection points to fill/refill AC.

Did you guys build the pressure with a vacuum pump for 30 minutes (to also evacuate any moisture) then let it hold for a couple hours to ensure no leaks?
 
Compressor

Does it repeat this cycle of turning on/off rapidly? If so, I would suspect the charge amount is incorrect. First make sure the belt is in good condition and that the tension is correct. If the belt is ok, check the pressures when the engine is running and the compressor is engaged. You should see roughly 200psi on the high side and around 25psi on the low side.
 
Ok ill check deeper into that on the pressures. The ac has been workin proper prior to changing the heater core. It would freeze you out. I have had to charge it with the store bought can periodically. I think once maybe twice since i bough the truck 3 1/2yrs ago.
 
Yes it seems to grab for a few seconds and then release... i have 98 truck i believe its a SR5 trim package.... dont hold me to that. I paid a local shop to do this portion for me, first thing he came back with is the valve was bad, Replaced it , and the compressor is bad
 
Compressor

If the system worked before, there is extremely small chance that the compressor suddenly went bad. My best guess is that the system is overcharged, which seeing the pressures would tell us. A bad expansion valve would not cause the symptoms that you're describing.
 
Greenmachine86 said:
Yes it seems to grab for a few seconds and then release... i have 98 truck i believe its a SR5 trim package.... dont hold me to that. I paid a local shop to do this portion for me, first thing he came back with is the valve was bad, Replaced it , and the compressor is bad
Click to expand...
Incorrect charge amount. Most likely too much refrigerant causing the ac high side pressure switch to tell the compressor to turn off to save the system from exploding.
 
Bad Luck said:
Incorrect charge amount. Most likely too much refrigerant causing the ac high side pressure switch to tell the compressor to turn off to save the system from exploding.
Click to expand...
Quote possible. Especially if the refrigerant wasnt measured or monitored going into the system.

OP do you know if they used a machine to charge the system or if they only used gauges and a big bottle of 134a?

Sent from my SM-J337V using Tapatalk
 
OP, I think you'll find this video informative. Same for anyone else that doesn't know a whole lot about how the AC system works on their rig.

Since it sounds like your system was exposed to the atmosphere for a decent amount of time, the desiccants in your receiver/dryer have been saturated by the moisture that's in the air. You should have installed a new receiver/dryer.

Those DIY refill kits can work, but quite often, people end up getting it wrong like people have mentioned on this thread by overfilling the system. The only way to know it's properly charged is with an AC manifold gauge set.

<iframe width="560" height="315" src="https://www.youtube.com/embed/zlRE0Zeeyrc" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 
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