[AT] Starter trouble

[Mike Sloane]

I have had various starter problems over the years. If you are "clueless 
on electrical", you might want to take yours to a competent auto 
electric shop (not one of the chain auto parts places).

The first thing I do with a starter problem (that isn't just bad 
grounds) is take the starter out and set it on a vise, attach  one end 
of a jumper cable to a battery and the other to the starter frame 
(starter motors don't care about polarity). Then I hook the other clamp 
to the other battery terminal and then touch the free clamp to the stud 
on the starter. There should be a hefty spark and the starter will try 
to jump as it spins. If you don't get something like that, you will have 
to start by taking things apart or take it to the shop for an "overhaul".

If a starter was working fine one day and then dead the next, it isn't 
likely that the problem is brushes or commutator (at least in my 
experience), as those problems usually result in just slowing down over 
time. Also, just because you have continuity at the switch doesn't mean 
a whole lot - your switch needs to be able to handle a couple hundred 
amps, not just the tiny amount needed to test "continuity".

I did have one starter where the wire connecting the stud actually broke 
away from the stud underneath, leaving me with no connection, but I 
consider that a very rare situation.

If you decide to disassemble the starter (just two long bolts), there 
are some things to look for: little bits of solder inside the housing 
(resulting from overheating and the solder melting), bare wires in the 
windings of the field coils (a sign that the front bushing has worn so 
much that the armature has rubbed the field coils), broken brushes, dark 
commutator (it should be shiny copper color), or any other obvious sign 
of damage.

Let us know how you make out, as everyone's experience (good and bad) is 
helpful as a learning too for others.

Mike

Ben Wagner wrote:
> Hello,
> 
> My starter on my Super A has all of a sudden quit working.  It was going 
> one minute, just a quick turn over, and the next time I pushed the start 
> rod the starter didn't turn.  I recharged the battery... still no life 
> out of it.  So I pulled the starter out of the tractor, and tried it 
> again.  No life out of it.  The switch works, I tested it for continuity 
> this morning.  Obviously, something in the starter motor itself is 
> making it not work.  I made sure it didn't bind, so I know it turns 
> freely.  What do you think is wrong?
> 
> Thanks, 'cause I'm clueless on electrical....
> Ben Wagner
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