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ac compressor clutch replacement

naterb27

Full Member
Joined
Aug 6, 2017
Messages
26
Location
Lafayette, IN
so I've been having some ac issues since i bought the truck. first bought it nothing worked, no blower, no mode change nothing. replaced blower motor and relearned blend doors eventually fixed that. then ac would start off blowing cold then would warm up at a stop, figured Freon was low and topped it off as it was the last few hot weeks before winter, that worked OK then.

next spring ac was blowing warm at idle again, i tried to top off again but the problem didn't go away, then compressor clutch stopped working alltogether. at the time i suspected the clutch coil, as my ac gauge read correct pressure(though i now suspect it was wrong), so i just dealt with no ac until this spring.

this spring i changed the low side switch and a fair amount of pressure bled out now I'm back to the ac warming at idle and eventually stops cooling after about a half an hour if temps are above 76. changed the fan clutch on a buddies hunch the warm at idle problem went away, but now doesn't work after about a 20min drive or if temps are above 75ish it doesn't kick on at all.

today i was reading on how to adjust the air gap for the clutch on another forum and the post mentioned the spec for air gap as .020-.030. poster said his ac was doing same as mine and his air gap was .045. i figured what the hell, I've got a day off, it doesn't look that hard and if nothing else i can at least see if i am in spec. spec-ed out a .039. now for my dilemma. the post described how to adjust the air gap, and an easy way for removing the bolt for the clutch plate.
i got the bolt out, but the clutch plate wont move, i tried prying on it a little and only managed to slightly warp the clutch surface. i may be able to straighten that out, but know full well i will probably have to buy a new clutch for it to be done right. but i cant get the old one off. any ideas? i don't think the crappy autozone puller will work on our tucks as there's no provisions for it. all the procedures and videos I've seen show people just pulling it out with their hands, but mine wont even come out with force.

like i said any ideas?

things i know as of now
ac clutch air gap 0.039"
coil resistance 4.5 ohms
loaded coil amps .5amps i think
ac relay commanded on, scan tool and verified at relay
have voltage at clutch plug w/ relay on
have 2-3 ohms from clutch ground wire to battery ground
no hvac codes
passenger window inop others slow so no 4-80 ac
no damage to ac system from recent accident, in other thread
little ac gauge broken
manifold gauge set has wrong hoses
 
What are pressureswhen blowing cold?
Does it blow cold where you can see if clutch engaged?

MAybe orifice tube is all clogged up...

Has system ever been opened? replace hose? or such
 
Compressor cycles off after start up and eventually stops cycling back on. The low side switch still closes, and the relay comes on but the clutch doesn't cycle on. My scan tool reads about 1000kpa until the last cycle off then equalizes to about 550 high side. My manifold gauges are missing an adapter so I can't check actual readings right now. But at this point I am convinced it's the clutch, after trying and failing to remove the clutch plate the clutch engages pretty consistently but slips pretty bad, right now have the relay out so I don't melt anything. If I could get the clutch off I could replace it or straighten out the plate to fix the slipping. I am tempted to just say f#*%$! it and throw a compressor at it, but I know my luck will make something else stop working.
 
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