AC Compressor Clutch help

i have been searching but i hate how if you type in "AC" its too short... and if you put AC Clutch you get regular clutches!!!!!... ahhh... whatever..

ok, old owner had the system converted, new compressor, new lines... thing stopped working... the compressor is not siezed up, i can turn the front clutch area by hand... whats throwing me off is when i turn the ac on in the cab the amp meter DROPS hard... something is grounding out or something..

what would the process of elemination be? what should i be looking at?

Sorry if it has been discussed before, i simply cant find it.

JOe

damn compressors are expensive

JOe

Does the clutch still turn when it engages? What happens if you have the blower on low? Does the air get cold?

The gauge is a voltmeter not ampmeter. Check your grounds.

i unpluged the lead going to the compressor (it Y's to ground on top, then inside the clutch).... with the compressor unplugged i can turn the AC on and the blower works, ect but of course, does not get cold (duh)....

once i plug that back in and turn the ac on the volt meter just about pegs down the scale and the compressor/clutch does not engage... it does not click or rotate the compressor itself.

i can rotate the shaft of the compressor by hand (engine off of course) so it doesnt appear to be siezed... but maybe a short inside the clutch i think.

my dad used to do HVAC and we hooked up the guages and its good, it is filled and there is proper pressure. (i posted this before i could ask him)... but him and I think its the compressor.

i think im gonna take my chances at the junkyard... maybe look for one rear ended and flush the oil and recharge.

JOe

The FSM says the current draw at the clutch coil should be between 2 and 3.9 amps with system voltage 11.5-12.5V. If the current draw is 4 amps or more, the coil is shorted and needs to be replaced. You might be able to find a boneyard compressor that you can scavenge the coil from. Replacement is pretty straightforward and doesn't involve loss of R134A if the compressor is otherwise OK.

-Ed Rico

shouldnt a fuse be blowin if there was truly a short

There is a 25 Amp fuse in that circuit. If your voltage dropped so radicaly when you turn the AC on, I would expect the fuse to blow. You already unplugged the clutch and did not see the voltage drop, so it has to be through the clutch circuit. I am thinking your voltage readings are in error (in addition to the AC problem). As previously mentioned, I would look for a bad ground as the cause of the low voltage reading.

Yep, sounds like the clutch is toast.

If you want, with the engine shut off, disconnect the same wire you did above (the Y) and jump it straight to the battery +. This should engage the clutch and you'll hear a loud CLICK like a giant relay. If it doesn't or if the connector sparks a lot (like jumping across the battery terminals), then it's shorted out.

You can replace the clutch but there's not a lot of room to get the puller in there unless you unbolt the compressor. You don't have to disconnect any lines so you won't loose your charge. Clutches are pretty expensive so a JY is a good option.