One job I do not look forward to is one day having to replace my belts (V-belts, fan belts, whatever they're called). I've been looking to see how I can extend their life, slow down the process of cracking and deteriorating. Here are a few things that I've learned. Please comment, disagree, or offer some other tips.
1. Any grit, sand, etc. on the pulleys will accelerate wear--thus it helps to keep the pulleys clean and free of grease that would cause grit to stick to them.
2. Maintain proper tension--too little tension causes belts to slip leading to "varnishing" of the belt.
Too much tension is also bad for bearings. To obtain a good tension, I've been using the "just enough to stop the belt from slipping" method. This involves either tensioning just to where the squealing stops, or in the case of the alternator belt, just to where the red "not charging" dash light is not coming on, especially when idling.
I like this method because it seems logical, but it wasn't perfect. I was still getting some alternator belt slip when starting a cold engine until it warmed up a bit. I was also getting a squeal when turning on the A/C, but this would also go away after 20-30 seconds. ButI think that I've finally cured this (see below).
3. Do not use "belt dressing" or "belt conditioner"--I could find nobody who likes this stuff, except for maybe as a temp fix for a slipping belt that either needs tightening or replacing. Also, nobody seems to believe that this stuff extends belt life, and may in fact cause deterioration.
4. White lithium grease--this was told to me by an old school mechanic. It has to be the stuff in a can, not a spray. At first I was skeptical and thought it may cause more slipping. But it eliminated all squeals and the red "not charging" light when cold. You can brush it on the pulleys with a small brush and rub it into the belts with your fingers. Do not use too much. Just enough to smooth, moisten, and "soften" the belts a bit. The only downside may be that the pulleys might be more prone to hold sand or grit. I will have to check and clean them, probably every 3000 miles, and then repeat the lithium application.
