I'm with Mike on this.  The OEM Vanagon setup has two pulleys of DIFFERENT
diameter on the water pump.  The crankshaft has a double pulley (same
diameter).  The outer pulley of the crankshaft drives the smaller outer pulley
of the water pump.  The inner pulley of the water pump is larger in diameter
and drives the alternator.  It is POSSIBLE to use a single belt from the inner
pulley of the crankshaft to the inner pulley of the water pump to the
alternator (they do line up).  However, this effectively lowers the rotational
speed of BOTH the water pump and the alternator as compared to the OEM setup.
 Not sure if this slower rotational speed actually hurts anything, but it is
not the same as stock.

Maynard Southard  (OvO) '79
'86 Double Cab Diesel "Col. Potter"
'82 Westy Diesel "Reinhardt"
'82 Vanagon GL Diesel "Sluggo"
'93 EV GL "Klinger"
'00 Golf GLS TDI "WooHoo"
'84 Jetta GL TD "Donor"

On Thursday, May 16, 2002 12:12 PM, Michael Snow <mwsnow@COX.NET> wrote:
> F.J. Stefanovich wrote:
> > Get one belt that will fit from alternator - water pump -
> > crankshaft pulley
> >
>
> The diesel Vanagon pulleys are not in the same plane.  Two belts are
> required.  At least some diesel cars (like my Golf) have a single belt,
> but they also drive the water pump at much lower RPM.  I would seriously
> question whether you could reliably turn the Vanagon water pump with the
> minimal belt to pulley contact provided by the single belt setup used on
> diesel cars.
>
> Mike Snow