<VV> Speedo

[Eric S. Eberhard]

The speedo and odo are driven by the same cable -- in different ways 
in different locations on the cable.  The odo is gear driven, the 
speedo is magnet driven.  They are not directly related except via 
the cable.  The odo is spot on.  I was trying to see if the cable 
first went through the odo, then the speedo.  In that case a "short" 
cable (or not properly seated cable) would cause this problem.  Since 
the problem of the "warm up" is more likely to be cable related ... 
it makes me lean that way, although the NOS cable I have is 1/2 inch 
less inserted into the speedo with same result (e.g. the portion of 
the cable past the seat is shorter).  That is why I am trying ... to 
see how it works ... I am going to try one more cable and then take 
apart the one out of the car ... and see where it goes.  Note also it 
CANNOT be stripped ... a piece of cable shoved in and turned with a 
dremel works perfectly (e.g. I can moderate the speed smoothly 
although the slightest slippage and it runs up to 100 mph).  So the 
one in and out of the car also behave the same with the dremel.  If 
they were stripped they would not work.  If the magnets fell off they 
would not work.  Also when it failed completely (stuck on 100), it 
went to zero when the cable was removed ... again indicating the 
cable was somehow holding it up there ... although since it is 
magnetic ... so I am rambling but I think it is not yet conclusive 
and this is mostly because I cannot picture how the internals of the 
speedo are.  Note that after the one stuck on 100 went to zero after 
lubing it, I swapped in the other speedo.  It also stays at zero -- 
when I removed it, it was working perfectly except for the problem of 
needing to "warm up" in the winter (just like the other).   So that 
kind votes against the speedos because not only would the two have to 
be broken in the same way, the one would have had to change it's 
behavior while sitting on a shelf -- in order to match the installed 
speedo.  At least the group has given me ideas and made me feel not 
so stupid as it is not so obvious ... Eric

Does anyone have a nice used or NOS speedo around?

Eric


At 01:27 PM 11/1/2011, you wrote:



> >I believe Harry but the situation is odd.  I had the problem, changed
> >the speedo, and had the same problem.
>
>When you are dealing with 50 year old parts, it is perhaps more 
>likely (than odd) that they would both exhibit the same failure, 
>mostly cause they are both the same age.  Finding one that works 
>would perhaps be the odd man.  If the odo works, and I do mean 
>accurately, not just changing on occasion, what do you think is 
>driving it if not a properly working speedo cable?
>
>The first gear set in the speedo head runs the odo, and then the 
>second set runs the speedo needle (magnetically) -- it doesn't take 
>much to keep the needle from moving, but more likely the shaft to 
>that gear has gotten stuck in the housing (lubrication is 50 years 
>old)and stripped the plastic gear on the other end.  Both units. 
>Normal failure.
>
>Bill
>
>Bill


Eric S. Eberhard
(928) 567-3727          Voice
(928) 567-6122          Fax
(928) 301-7537                           Cell

Vertical Integrated Computer Systems, LLC
Metropolis Support, LLC

For Metropolis support and VICS MBA Support!!!!    http://www.vicsmba.com

For pictures:  http://www.vicsmba.com/ourpics/index.html

(You can see why we love this state :-) )