(ET) e-15 eats reverse relays

["Pieter Litchfield" <plitch attglobal net>]

Gang:

My e-15 w/bucket loader has a nasty habit of eating the reverse relay - it
welds or fries the contacts while in reverse, or when switching from 
reverse
to forward modes.  Over the past several years it has eaten 3 or 4.

I am now using the improved Bill Gunn relay, and while definitely stronger,
the tractor's demon is stronger still.

I had assumed that perhaps the motor of a rolling  tractor acts as a
generator and that shifting too quickly from reverse to forward might allow
the motor to weld contacts (or something).  I do notice a spark when the
rely breaks contacts with the reverse contacts if I shift it without the
motor coming to a standstill, even with the tractor in neutral.  No spark
seems to occur when the motor is completely stopped.  However, this could
just be coincidental with something else - like a component that looses a
charge over a short time.

I do have the complete "homeowner's repair manual", but I ain't no 
engineer,
so I look at the pretty pictures of wires and remain more or less clueless.

I'll ask Bill when I order more relays, but does anyone else want to 
venture
a suggestion as to why I eat relays?

Thanks!