it works on properly tensioned belts too.
the overall layout and arrangement matters too of course.
you can't do it on 'just any' v-belt.

you might think it silly.....
but say you are replacing a water pump on say .........an old toyota
truck.....4 cylinder.
On some engines there are 3 belts, and thus 3 adjustments.
if you can just flip those belts off...........or one or two of them.......
what you save is ......digging through horrible grease and crude, and
figuring out how the adjustment works.
Sometimes the adjustment system is obvious - sometimes it's very, very
cleveraly hidden.
so you save having to figure out out to de-adjust the belt tension,
and you save having to de-adjust it, once you figure out how.

then going back together........you save having to adjust tension at all.
Unless of course, they need adjusting anyway .....
but in cases where you just need the belt off briefly, and it's not hard to
do safely ......
it's a good time saver.
and of course everyone knows that you mark v-belts as to which way they
turn, so when putting a used one back on, you keep it going the same way it
was before.
Scott

----- Original Message -----
From: "neil n" <musomuso@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Monday, October 26, 2009 3:57 PM
Subject: Re: Change a VW Fan Belt In 5 Seconds?

> On 10/26/09, David Beierl <dbeierl@attglobal.net> wrote:
>> At 05:28 PM 10/26/2009, Scott Daniel - Turbovans wrote:
>
> ....
>
>> I think it's a cute trick, but I notice the belt wasn't at working
>> tension beforehand. .....
>
>
>
>
> Yah I saw that too. Looked all floppy like.
>
> Lets see him remove an adjusting shim while it's running!
>
> Or remove the alt belt off an air cooled Vanagon!
>
> Ha!   ;)
>
>
> Neil.
> --
> Neil Nicholson '81 VanaJetta 2.0 "Jaco"
>
> http://tubaneil.googlepages.com/
>
> http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engines