Hey guys, i have had a problem that i need some advice on.

My truck just hit 270,000 miles and things are starting to break down some, as expected. The latest issues is the AC System. My AC has worked flawless the entire life of this truck except for a few things. The clutch / compressor has had a tick sound for years as it was engaged and the blend door has always been noisy. Now just recently, the ac started blowing cold and warm randomly and now it just all together quit working.

Since then, i pulled some fuses and noticed the #11 fuse was blown. I put a new fuse back in and when i turned on the AC it burned up immediately. I disconnect the AC compressor and it no longer blows when i turn on the system, so i am assuming it has something to do with the compressor / clutch. Also in the last few weeks there is a sound at startup that almost sounds like a grinding noise. It is real loud at startup but after 10 -15 seconds it reduces 80% or so. You can still hear the noise but it is greatly reduced. it almost has the sound of dragging something across a sandy floor.

My question is this... do you think this could just be clutch related? or should i replace the compressor and clutch? the ac worked fine when it engaged, but now i can't get it to engage because like i said earlier it pops #11 fuse immediately.

Any help would be appreciated.

Thanks.

 

Remove the serpentine belt and check the compressor pulley for degraded bearings.

 

will do. thanks projectSHO89.

 

Just to close this thread....

After closer inspection and taking the belt off i noticed the ac clutch was in real bad shape. the bearing was completely falling apart and the winding in the field coil was coming to pieces. Instead of opening up the system, i just decided to replace the clutch. I removed the intake duct, fan/shroud and the belt. Once all this was removed i was able to access the clutch rather easily. i did have to use a 3 jaw puller to remove both the pulley and field coil. once everything was back together, the system now works without blowing a fuse and the under hood noise is completely gone.

thanks for the reply projectSHO89, you put me on the right path.

 

Yeah, that's what I figured. The failed bearing allowed the inside of the pulley to rub on the coil and, once the insulation was gone, caused a short to ground through the pulley.

FWIW, you were probably thisclose to having the pulley seize and lock up the motor.

Glad it worked out!

 

I had this same problem on my '00 Dakota a few years ago. Compressor was good, but the bearing was shot and tore up the field windings.

Just as a tip, make sure your new a/c clutch is properly adjusted. I was taught to make sure it is roughly business card thickness for the gap.

 

projectSHO89 - absolutely feel blessed that the whole thing didn't lock up as you described... about 1/3 of the ball bearings were missing in the bearing... it looked pretty bad.

ManualF150 - i actually used a business card to measure it, since i couldn't find my feeler gauge around midnight. haha.

Everything is working much better now. Thanks for the replies guys.