Bryan,  you directly jumpered across the heavy 
terminals.  That will spin the motor but as you 
found out on this type of starter it won't engage 
the pinion with the ring gear.  To do that you 
have to energize the control terminal, which is 
either of the two spade terminals sticking out of 
the [forward-facing] back of the starter 
solenoid.  One of those should have a #10 wire 
from the ignition switch plugged into it.  The 
other is spare or has a little wire plugged in that has no function I know of.

If it cranks well by jumping the control 
terminal, then either the wire from the switch 
isn't plugged in, or the switch is bad.  If it 
doesn't, the starter solenoid is bad, and tapping 
the side of it firmly with a hammer a couple times may free it up temporarily.

David

At 11:03 AM 10/23/2015, B Feddish wrote:
>How do I test to see if it’s the starter switch?
>
>Thanks,
>Bryan
>
>Sent from Mail for Windows 10
>
>
>
>From: Jim Felder
>Sent: Friday, October 23, 2015 11:00 AM
>To: vanagon@GERRY.VANAGON.COM
>Subject: Re: Trouble starting
>
>
>Starter switch?
>
>Jim
>
>On Fri, Oct 23, 2015 at 9:46 AM B Feddish <uprightbassghost@hotmail.com>
>wrote:
>
> > I am scheduled to leave later today on a camping trip.� �  The van battery
> > was dead because I left the interior light on 
> the other day.�  I charged the
> > battery and turned the key but nothing happened. I tried to jump start but
> > nothing.�  The starter makes no sound 
> whatsoever.�  If I crawl underneath and
> > connect to 2 large connections together the starter spins but does not
> > engage.
> >
> > What are the next trouble shooting techniques to determine what is wrong?
> >
> > 1983.5 WC
> >
> > Thanks,
> > Bryan
> >