alternator belt spec

ive tried searching on here as well as google.

about a month ago i replaced my alternator and ever since it has squealed pretty loud on initial startup for a second.

i cannot find the spec for how much movement the belt should have up and down.

anyone have an idea? im sure its not tight enough

 

Quick test:

Start the truck, put on the lights, switch to high beam and rev it up to 4,000 for a second. Chances are if the belt is too loose it will squeal.

 

The dealers have an SST for measuring proper tension/deflection. What I do when a belt squeals, is to tighten the belt a little more and see if the squeal is gone. If not, tighten it up a bit more. You don't want it too tight, or it could shorten the life of the belt and/or bearings.

 

it squeals when revved up after startup. seems to me like its too loose. i will tighten tomorrow and try again.

i was thinking maybe there was a measurement, but ill just tighten little by little until it stops

 

You want roughly 1/4" deflection at mid-belt when it is tightened. That's what I use and recall reading at some point. Works for me.

 

thanks! will try to figure a way to roughly measure it

 

I thought it was 1/4" too!!

But yeah just keep going till she stops that terrible noise, but if you go till the belt is so tight it has no deflection youve got something going on...

 

The eraser on a new pencil (remember those? wooden things that people used to write with) is 1/4 inch long.