<VV> Erratic Tach with Crane/Allison Ignition

[tony.underwood at cox.net]

---- Mikeamauro at aol.com wrote: 
> "...Hi Mike,
> 
> I have the Crane XR700 ignition  on our Greenbrier but not the Safeguard
> unit.  Never a problem with the  tach up until about a month ago.  It is a
> Spyder tach and I suspect that  it is just old components causing the
> problem..."
>  
> Thanks Dan... I believe I should temporarily patch in another  known good 
> tach to see if the problem goes away with another tach.   



Keep in mind the factory style tachs are not that difficult to repair if it's an electronic issue and not a meter movement problem.   
Schematics are available courtesy of the membership here.   Ask for a link and they'll post them... or I will if I can remember the url...   lol  


tony..