Re: (ET) New failure mode...

["SteveS" <ssawtelle fcc net>]

I had a somewhat similiar problem (E12S) - reverse ok, forward 
intermittent.
In my case the the reverse relay contacts had welded. One reverse contact
welded the common and wouldn't let it touch the forward contact.  Well
actually it finally did and blew off the end of the relay.....

Is this the problem I've heard that arises from not stopping completely
going from forward to reverse?

Did someone find a better protected version of this relay - I don't like
those contacts out in the open.

- SteveS
E12Ss
E20 (which I got running this weekend!)




----- Original Message -----
From: "Elie, Larry (L.D.)" <lelie ford com>
To: "Elec-trak list" <>
Sent: Monday, June 30, 2003 10:21 AM
Subject: (ET) New failure mode...


> Well, it's new to me, and even Bill hadn't seen it...
>
> My E12 was working fine until last fall, suddenly I couldn't go forward
> sometimes.  Move the control a few
> times and it would take right off.  Hmm...  I checked the manual, then 
> the
> forward contactors.  They were
> fine.  I replaced the reverse micro-switch.  Slowly the problem got 
> worse,
> until it only went forward about
> 10% of the time.  I finally called Bill Saturday.  He said I must either
> have a bad contactor or a bad reverse
> switch as the speed control runs the same circuitry forward and reverse,
and
> reverse was fine.  I agreed that
> this is what it looked like, but I'd already tried everything.  I could
see
> the control closing all the
> micro-switches.  Foreword just wouldn't work....  Then, while engaged
> 'forward' I pushed the start (first) micro switch with a small blade
> screwdriver, the motor started instantly.  What had happened is the
circular
>
> plastic speed control spirals that close each micro-switch had worn more
> from forward than reverse, the start
> switch was not closing most of the time; the switch moved but not enough.
A
> simple bend of the bracket with
> pliers of perhaps .050" was PLENTY and the control works fine now.  I
called
> Bill back with the tip, and I'm
> letting everyone here know too as this was NOT an electrical problem; 
> just
> mechanical wear.  Since the
> E12/14/15 use the same sort of plastic controls, and all our tractors
> probably have about the same amount of
> wear, I'm expecting others to begin to see this behavior eventually.
>
> Larry Elie
>
> _______________________________________________
> Elec-trak mailing list
> Elec-trak cosmos phy tufts edu
> https://cosmos.phy.tufts.edu/mailman/listinfo/elec-trak
>