W124 Serpentine / Bearing question
This weekend I pulled the serpentine belt off of the '90 300E to replace it and check the bearings on the front accessories. After some recent posts on fan pulley bearing failures I wanted to take a look. Well, the replacement belt I had was the wrong length, so I'll get to do the job again, but it's easy anyway (maybe 20 minutes if you've done it a few times).
With the belt off I checked each accessory and idler by pushing and pulling to simulate a side load from the belt and also by giving them a spin to listen for "rollerskate" bearing sounds and check the smoothness. I found no clunky bearings and no noise. The fan pulley bearing spins very freely and will keep free wheeling for 15 seconds or so just with a spin by hand. The other idlers will go for 5-10 seconds as well. I think they're in good shape, but it seems that most of the grease must be gone if they spin so freely.
M.B.DOC, Mike Freeman, do these pass the test? Anybody else have comments or experience to share? I'm thinking that I'll leave them alone, but start performing this test every 5,000 miles or so to keep an eye on things. Does that sound like a good plan?
Experience is something you don't get until just after you need it.