AC clutch is not picking up on a 1995 Ford F-150 XLT, 4.9L, 159,000 miles with AC in normal or max. Truck AC or defrost hasn't been used in 12 months (my mistake...) I have 12 volts after disconnecting clutch pressure cycling switch. Jumpered this with a paper clip. Disconnected AC clutch cable connector and I'm getting 0 volts... This does not make sense. Clutch spins freely with some resistance by hand.

Is there something else I am missing?? 15 amp fuse is good. Relay?

 

Is there any refrigerant left in the system?

 

What's the static system pressure, and what's your ambient temperature right now (where are you)? If it's below 70psi, get the leak professionally repaired before continuing.

 

Guys, I do not believe there is very little R-134a; I bumped the shrader valve and a little discharge was observed.

After smacking my head around, I read a few more posts and rechecked the jumper and it was a litlle loose, retested the A/C by bumping the clutch plate with a piece of wood and it intermittently moved and a little smoke came out of it and hurried and shut it down so I would not damage the compressor, if it is still OK. I believe it could be the clutch... Would the clutch job be a DIY???

I did not check pressures, but I hope to test it tomorrow.

Compressor, I hope is OK....

Thanks for your guy's initial responses.

I sure wish I would have found this forum earlier in my F-150 days... Such a wealth of info.

 

...NOT very little... What exactly did you do, and what do you think that tested? Where did the smoke come from? Was the engine running? Was the clutch getting power?

You REALLY should take it to a pro.

 

Steve,

First off.. I do the very best I can.. I wish I could bring everything to a professional, but sometimes you have to learn a little on your own, my mistake... What I wanted to test was whether the clutch would engage or not. It appeared that it may have bound up a little and a little assistance with a piece of wood, with the engine running, was what was needed (this was performed by a guy in one of the previous posts and appeared this technique was not condemned). I shut off the AC after the clutch was engaging and disengaging intermittently. The smoke was coming from the front plate next to the pulley.

Yes, I plan on having a professional evacuate the system, look for leaks, then recharge it with freon and the PAG oil specified by the sticker attached next to the radiator.

The question I have: Does the smoke that came from the clutch air gap area point to the clutch or something bigger?

Respectively, Kurt

 

I can't tell since you didn't answer all my questions. I do the best I can, too, but I can't see your truck. You have to write it, and all I can do is read what you write. If you write something confusing, I'll be confused. So take an extra second or 4 to proofread your post, and try to imagine how it comes across to someone who wasn't there.

If the clutch DID have 12V when you hit it with the wood, I'd test the coil's resistance and the strength of its magnetic field. If it DIDN'T have 12V, I'd guess the compressor is seized, AND the system is discharged (probably through an overheated shaft seal at the center of the clutch).