Every manual I've seen has all kinds of specs for the "Vee" belts,
> serpentine belts, and Gates belts. Typically, they tell you to adjust the
> idler to a certain deflection at so many pounds force at the center.
> Tighter for new belts and looser for used. Another method is with an
> expensive special too. A third method is to use a torque wrench on a
> tensioning bracket. This is often impossible with the engine in the car,
> so I don't quite get the logic for a field manual.
>
> Well, here's a better method and it works on all friction belts. Start
> tightening the belt while applying a rotational force to the driven pulley
> by hand. For instance, the alternator belt. If you can turn the pulley by
> hand easily (the crank being stationary), the belt is too loose. Turn in
> both directions and adjust for the maximum resistance. If the pulley can
> just be turned in the belt with maximum hand turning effort, the belt is > okay.
>
This may be fine for you but before anyone does this regularly they should definitely get the feel for it by using a belt tension guage to tighten the belt to the correct tension, then turning it.
This also only works on alternator pulleys, pulleys on things like smog pumps are much larger, have much more surface contact, and will seize up before the belt has proper tension.
It also doesen't work that well on cheap rebuilt alternators where the pully has gone through a bead blaster and now has high friction.
There are also short cuts for bolts and nuts. No need for torque wrenches.
> Snug down your bolts, then give an extra 1/8 to 1/4 turn with a quick
> "umph" on the wrench. Do it in one quick motion rather than in steps,
Once again, this is fine if your tightening some non-critical part like a radio speaker hold down bracket or some such.
But it's really stupid on any kind of serious load bearing fastner. (like a head bolt)
Ted