Re: (ET) Mower motor stopped

[David C Robie <mycroftxx1 juno com>]

YES IT IS.   (1) testing with an ohmmeter, the commutator bars will
normally test as 'shorted together'.  The only way to get a true reading
on an armature winding is to use an armature growler, which rebuild shops
have.   But the armature is not your problem.

(2) A bearing shop can press on a new bearing.  All ball bearings have
numbers on them which reference to standard numbers.

(3) As to the field magnet, you are fortunate that it didn't crack up
into small pieces.  Clean the area that it goes on real good with
solvent, get it squeaky clean.  Same with the backside of the magnet. 
But before you do this, make a mark on both magnet and case as to the way
it came out so you can put it back in exactly the same place and the same
direction.   There is a 2 part  epoxy product called 'JB WELD' ,
available in hardware stores that has successfully reattached countless
field magnets, even mended ones that came out in several pieces.  Use it
as directed, smear the entire back of the magnet and clamp it tight to
the case in the exact position it was before, shown by it's outline in
the case.  Do not worry about the wear marks on the magnets, just be sure
there are no magnetic particles stuck to either magnet or debris stuck to
the armature when you reassemble.
       Note that case reassembles only one way.  There are tiny notches
and tits in end pieces, likely painted over.  These gotta line up for
reassembly.
     This writer knows a former GE Electrack dealer local to here who
retired from his business just because he was sick of reattaching and
otherwise fixing deck motor field magnets.  I can relate to that,  so am
I.  But it's gotta be done. It's the easiest (and cheapest) way to get
mowin again.

Before putting her together, look at the brushes and their holders. It is
common that a burr builds up at the bottom of these holders and restricts
free brush motion.  If so, using a fine stone rather than a file, remove
the burr and check for free motion.  If the brushes are too worn,  the
pigtail pulls up tight or catches at the brush top to keep the brush from
contacting the commutator.  So get new brushes from Harold (in PA) or if
not badly worn, route their leads so as not to hang up.  Make the
commutator clean with extra fine non metallic (scotchbrite) abrasive
never use steel wool.  Do the cleaning in the 'across' direction, not
inline with easch bar so as not to create tiny ridges that wear brushes. 
Copper is soft, although it looks hard to you it's easy to scratch with
abrasive.  Or anything.

Before puttng her back on the deck, test with a 12V battery.  Torque will
be enough to roll her off the bench so hold her down tight.  Like between
concrete blocks.

Best of luck 2U

Dave
Weymouth MA




On Wed, 18 Oct 2006 01:21:30 +0000 bill4betty att net (Bill Alburty)
writes:
> On my E-12, one mower motor stopped. I took it apart and found the 
> lower bearing very rough. One magnet had come unglued and had wear 
> marks on part of it. The armature looks good to me. No gouges and 
> the commutator bars are clean. Brushes look good but the commutator 
> bars are electrically shorted together. I think it was pretty hot 
> due to the bad bearing. I haven't been able so far to pull the 
> flange off the shaft so that I can remove the bearing. Is this thing 
> fixable?
> 
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