Calculating v-belt tension - Honda to Mitsubish - help

I'm trying to solve problem with a Mitsubishi v-belt tension
without using a service manual. I've been told that it should be
possible to deflect the belt about 1/4" in the center of its run
with finger pressure. But I will try one other trick since they break
too often. A service manual for a 1986-1989 Honda Accord says
to apply 22 pounds of pressure then:

The 5" span alternator/water pump wide belt should deflect 4-
6 mm new, 6-9 mm old. The 9" span narrow AC belt should
deflect 10-12 mm. The 12" span narrow power steering belt
should deflect 14-17 mm.

If:

5" = 5 mm, wide belt
9" = 11 mm, narrow belt
12" = 15 mm, narrow belt

Then:

7 " = what mm, narrow belt?

The narrow belt spans 7" on my Mitsubishi's alternator/
water pump compared to my Honda.

Thanks

 

Set it loose. Start engine. If it squeal, add more tension. If it's a new
belt, it would squeal again overnight with a bit of driving. Add a bit
more tension, and that will set it for life.

 

it's one of those things you just get a feel for. Too loose and it will
squeal and too tight will cause worn out bushings/bearings.

 

That makes sense. I just came back from installing a new belt.
It squeals when I set it to deflect at 7 mm. So I set it at 4-
mm and it doesn't squeal. I guess my work is done. Thanks.

I think I've found the reason my belt breaks too often. I'd been
using cheap aftermarket belts. I compared a genuine belt and
the aftermarket belt during my installation today. It was a huge
difference. The aftermarket is tiny, flimsy, rubbery compared to
the larger, rugged leather-like genuine belt but costs 4 times more.

Tibur

 

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Tibur,

The cheap belts are sometimes uneven in thickness, which makes them hard
to adjust, and lots of vibration when spinning. Can't be too good for
your bearings either.

'Curly'

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