alternator belt adjustment

[jpsenft]

I would like to eliminate a belt squeal before leaving for Williamsburg.   Referring to the diagram from the tech section

http://www.sl113.org/wiki/uploads/Electrical/alt1.jpg

What steps need to be done to  slightly tighten  my alternator belt?   I guess I don't see from the picture how tightening (or loosening) the adjuster nut 2 moves the alternator AWAY from the block to tighten the belt.  Which bolt(s) need to be loosened before adjustment?   What drives the alternator away from the block to tension the belt?  Do I need to use a pry bar to push alternator away and then tighten everything?
Thanks,
Jim

[WRe]

Hi,
First  loose nuts 3 and 7 a little bit to make the alternator free to move.
Now you can tighten/loose the belt with nut 2: up to tighten, down to loose.
With nut 1 (counter or lock nut) you fix nut 2 after adjustment.
Don't forget to tighten nuts 3 and 7 again.
...WRe

[jpsenft]

Thanks....This is what I thought, but I still don't understand how loosening the adjuster nut 2 (up the shaft) "pulls" the alternator out with it, thereby tightening the belt.  Even if nut 3 is loosened, what pushes the alternator out (tighter)?
Thanks again,
Jim
230SL

[WRe]

Hi,
Look here at parts 89 and 97: www.sls-hh-shop.de/en/230-280SL-W113/15-Electrical-Equipment-at-Engine/15-c-Starter-and-Generator/.
Nut 2 pulls/pushes the clamp block with the clamp screw 3 through it's channel.
...WRe

[jpsenft]

Thanks!  That explains it.  My problem was thinking the adjusting nut was a simple nut.  Could not see the lower half of the nut assembly which actually "pulls" the alternator out.
Jim