Topic: How tight is tight

[zowtiak]

Hey everyone! i finally got my wrenches ready to adjust my serpentine belt on my 95 YJ with the TJ adjuster. The belt flops a little bit, and does not look like it is going to fall off, but how do I know how tight is tight? 
The "book" shows I need to get a Nippondenso belt doo-dah to measure it. YIKES. Should it have a little play or be taught (sp?) this is a hard one to describe, so if i can offer more info i gladly will.

[zowtiak]

I am replying to myself.
anyway, i found this while surfing:
" Proper tension is about 1/2” of deflection per foot. So if you have one foot of belt between pulleys then the belt should move about 1/2” off of centerline."

Thoughts?

[smashcoast]

1/2" is good.

[Jeffy]

It needs to be tight enough that it doesn't slip.  Any tighter and you're just stretching the belt and putting more load on the pulley bearings.  General rule of thumb is about 1" deflection between the largest span between two pulleys.

[zowtiak]

Thanks. i owe you both a beer , if ever in S.Oregon.

[dwtaylorpdx]

With a serpentine belt I always use the 90 degree twist on the longest segment.
If you can just twist it 90, with your fingers its darn close.

Dave

[Dylan]

I've always used the "1/2 inch deflection with firm thumb pressure in the middle of the belt" approach... works for serpentines and v-belts.

[sharpxmen]

not sure if this is the right way to do it, i have been twisting it to 90deg on the longer side between pulleys - any less is to tight.