jdbeck

hi folks!

I have an 05 express 3500. 22K miles.

appreciate any tips on how to solve this:

About 1 yr ago, I snapped an a/c belt. so I replaced both belts, main and a/c and the a/c tensioner. (it was a bit wobbly ) .

Lost another belt 6 months later.

Now 2 more belts in 4 months this spring.

The pulleys look great. no sign of a gouge or burr.

My only clue is that occassionally, the van makes a noise in the rt front under acceleration that sounds like a guy with an impact gun beating on a stuck nut.

The van is more likely to snap a belt on a warm start. ie - drove to grandma's. inside for 1hr or so, then start up. wifey has lost the belt 2 times in that scenario.

my guess : too high pressure in the a/c causing compressor to chatter. but I gotta be sure before tearing into that beast.

Thanks !

jeff

stewdogg

So is the belt snapping within a second or so after startup or is it smelling like rubber before it snaps (and takes a min or so)? It sounds like it could be some pullys out of alignment.
If you suspect the ac compressor of being the culprit then you could pull the compressor/ac relay to stop the compressor from kicking in. When the compressor turns on does it make any kind of grinding noise?

jdbeck

No burning rubber smell. mainly the problem happens on acceleration. like pulling out from the driveway, or a parked position. the 'impact gun' noise happens then. (but not on a regular basis, which is why this is a bugger to track down.) Switching off the a/c stops the 'noise' . Could it be the a/c clutch or maybe belt slap?? The damaged belt looks as if someone pulled it apart. They snap across the width of the belt cleanly, with a few fibers visible. sort of like putting the belt to a stress test. No griding from compressor normally. Obviously, i can't tell if it is grinding while driving. But up on ramps, no belt on, the pulley rotates freely and smoothly.

stewdogg

Does the A/C work? Sounds like a stuck a/c compressor to me. I wonder if the "impact" sound is the belt jumping the a/c pulley because it won't turn?