Date:         11 Sep 1995 14:14:25 -0700
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         "Harvey Chao" <Harvey_Chao@smtp.svl.trw.com>
Subject:      Re: Need a speedometer

                      RE>Need a speedometer                        9/11/95

Posted to the net after seeing another message indicating more than one of us
has had this problem.
==================================================


[delete] The speedo works, but the odometer/tripometer is dead. Sure would
like to
have an odometer/tripometer again, especially since my gas gauge
is flaky, and I was using the tripometer to keep track of when to
fill up the van. The only one I could find near Cleveland was
$250, which sounded high to me. Could one of you guys fix me up
with one? How much would it cost? Any help would be appreciated

Lisa

A common failure mode for VDO speedo/odometer/tripmeters is the gear that
drives the tripmeter off of the odometer.  This is a small plastic (nylon?)
gear on the extreme right end (as you look at the face of the speedo)of either
the trip or odometer shaft that transfers motion from the upper (odo) to the
lower (Trip) shaft.  

To access this, you have to pull the speedo.  I had this same problem with my
'81 Rabbit.  What happens is that this little gear cracks radially, and then
doesn't grip the shaft tightly enough to turn with the shaft and transmit
torque to the other shaft.  

A fix I have known to work for gears is as follows (memory is dim here) --

The cracked gear has a smaller diameter hup than the teeth that engage the
other gear.  The outside diameter of this shaft was an excellent fit for the
inside diameter of a vw pushrod tube.  My mechanic showed me how to use a
hacksaw and slice off a "doughnut" from an old aircooled pushrod that would
fit over the gear's hub and hold the thing together tightly enought to resume
it's function.  If I remember, the complications are:
1)  not all pushrods have the same inside diameter, you need to "find the
right one"
2)  You need to pull the speedo and then the particular gear off of the shaft,
make the rapair and then re-assemble.  The gear in question can be slid on and
off the shaft with a carefully applied pair of needle nose pliers.
3)  In unlucky cases, the crack will either go all the way across the gear, or
there will be more than one crack and the gear will then be in more than one
piece.
4)  Some people have tried to glue the gear back together, but I think the
problem is that most glues won't properly "grip"/adhere to the plastic.
5)  In lieu of a section of pushrod, try a visit to a good hobby/model store. 
If I remember, they stock 12" lengths of thin wall brass tubing in concentric
sizes.  Maybe you can get something there that you can slice a section from
that will do the job.

However - It occurs to me that although the speedo faceplate may vary between
Vanagons and rabbits, it is a fair bet that a VDO speedo of the same year
vintage regardless of vehicle (as long as the top end speed markings are the
same) is a VDO speedo, and you may be able to cannabalize parts.  Just be
aware that this was not an uncommon problem, and a used speedo may have the
same problem.

Another possibility is ask that place I told you about in LA if they can fix
your speedo or if they will sell you a replacement gear.
Harvey