[AT] IGNITION advice needed

[Stephen Offiler]

Hot coil and sudden shutdown are classic symptoms of a bad coil.  I'd
replace it with a proper 12V coil.  It may seem to work if you add an
external resistor, but the coil is already compromised.  The problem that
causes the sudden shutdown is an insulation breakdown on the secondary
winding (high voltage side).  When cooled back down the tractor runs again
because thermal contraction moves the failed parts slightly.  It is still
failed.

SO

On Sun, Oct 15, 2017 at 1:33 PM, Ronald Cook <ron at lakeport-1.com> wrote:

> A friend brought me an A John Deere with carburetor problems.  He wanted
> me to get it running right for him.  The carb was no problem and the
> tractor runs decent until it shuts off unexpectedly.  Sometime in the
> past, someone has converted the WICO mag to operate like a distributor.
> This is a 1948 model, so it is 12-volt.   It is using an external coil
> that is not internally resisted.  Just a hot 12-volt source from a
> switch to the coil.  It gets hot.  Will this set up work alright if I
> put a resistor in the system or get an internally resisted coil?  If it
> were mine, I would put a distributor on it and it would be fine. Or
> overhaul the mag so it would work.
>
> Ron Cook, Salix, IA
>
>
> _______________________________________________
> AT mailing list
> http://www.antique-tractor.com/mailman/listinfo/at
>