[Vwdiesel] Funky Odo

[LBaird119 at aol.com]

In a message dated 6/26/2005 1:19:00 PM Pacific Standard Time, 
scameron at compmore.net writes:

> They are calibrated in 2 ways, adjusting the tension of the spring, , and a
> magnetic "shunt" across the gap in the magnet .
> The magnetic "shunt" across the gap can be moved to shunt more or less of
> the flux, varying the pull or drag the magnet exerts on the drum.
> 


  Don't think they adjust the spring.  I watched and asked a bit as a guy 
was calibrating one.  First the needle is set to the mark below the 
stop peg.  Then the speedo is run at the rpm indicated by the little 
number on the bottom of the gauge face.  If it falls on 60mph then 
he pretty well quits there.  Otherwise he adjusts the magnetic pull 
on it.  I believe he said there was a depth adjustment for how much 
of the drum is set inside of the other.  Didn't mention anything about 
a shunt but different speedos sure could be different in that respect.
    Loren