Hi all;

I'm attempting my first tune up on my 84 Vanagon, DH series motor, and
have some head scratchers.  In order to set the idle RPM to the
specified 850, I have to turn the idle adjustment screw so far
counterclockwise that I can hear air start to be sucked in by the screw
threads.  Intuitively, this seems excessive but not having done this
before I don't know.  Is  this normal?  The idle speed was about 700 RPM
before I started playing with it.

When I checked the timing, it is advanced from TDC.  I understand that
this is done some times to increase power.  My problem is more basic
though in that my Bently manual does not explain how to actually change
the timing.  How do I go about advancing or retarding the timing?

thanks much for the help

Matt