Date:         Wed, 24 Aug 2011 11:18:35 -0400
Reply-To:     David Beierl <dbeierl@ATTGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Beierl <dbeierl@ATTGLOBAL.NET>
Subject:      Re: V-Belt tightness -- how to determine?
Comments: To: Rocket J Squirrel <camping.elliott@GMAIL.COM>
In-Reply-To:  <4E550713.2040606@gmail.com>
Content-Type: text/plain; charset="us-ascii"; format=flowed

At 10:13 AM 8/24/2011, Rocket J Squirrel wrote:
>How much pressure do you put behind your thumb when testing? I can
>deflect the belt anywhere from not much to a lot more by pressing harder!

Bentley 27.21 gives the tension specs...our belts are just over a
meter long so use the larger spec.  "Thumb pressure" means the amount
of pressure an ordinary person can exert with his thumb with
reasonable exertion.  It's a common-sense measure - use your common sense.

The actual spec is in pounds of linear tension in the belt and I
wouldn't be surprised if it were in the neighborhood of 125 lb for
our belts.  It would be measured by a spring gauge that deflects a
controlled length of belt, undoubtedly like the one Steven
mentioned.  But everyone has a thumb.  If the belt squeals when the
weather is cold, recalibrate your thumb 21.47% tighter.

Note that the spec is tighter for a new belt.  A new belt is defined
by at least one belt mfr. as one with less than five minutes of running time.

Yours,
David