Advice for maintaining belt tension

[GordMay]

Originally Posted by Bluechart

Caution: over tightening the belt can damage the water pump bearing.

After adjusting the belt to your engine specs, tighten the adjustment bolt AND the alternator pivot bolt. On my engine the deflection for a new belt is 6-8mm, used belt is 8-10mm.

I have marked the bracket with a line as a reference.

The proper tension, for operating a V-belt drive, is the lowest tension, at which the belts will not slip, at peak load conditions.
There are several methods, used to measure proper belt tension, including:
* the Force-Deflection Method. [see #1 below],
* measuring the Frequency, of a vibrating belt.

[1] “Proper Belt Tensioning” ~ by BesTorq power transmission products
➥ https://www.bestorq.com/library/techinfo/whytension.pdf


See also:

“Belt Tension Calculator” ~ by Gates
➥ https://www.gates.com/us/en/knowledg...alculator.html

“Recommended Belt Tensions” ~ by Dayco
➥ https://www.daycoaftermarket.com/wp-...T_TENSIONS.pdf


FWIW: As a very rough guide, I used to expect about 1/4" - 1/2" of finger push deflection, for every foot of pulley separation.