B&S 12V starter quit working

Captn Cliffy

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I have a B&S engine 280707-0128-01 on a Snapper RER. First question, is it normal for the positive terminal on the starter motor to be grounded? It's a B&S 12v 4-9/16" housing starter motor. With the push-button starter switch closed, I have 12V to the positive terminal on the starter, but it does nothing. I discovered that the positive terminal on the motor is grounded - if I put one voltmeter lead on the starter motor terminal and the other on the positive battery post, I get 12V. So, the starter terminal is grounded. Is this normal?
 

StarTech

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Well you are kinda contradicting yourself here. IF you got a 12v at the starter terminal with the push button starter switch depress it can't be shorted. If you reading the second way with the starter push button not depress sounds right as the starter has extremely low ohm-age as it pulls close to 80 amps cranking. Now starter can be shorted but you would notice cables getting very very hot and sparks flying when you attempt direct connections.

Even free spinning the starter will pull 15 to 25 amps depending which internals it has.
 

tom3

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I'd guess you're getting a ground through the starter windings with the open circuit.
 

Captn Cliffy

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Figured out the reason why the starter wouldn't do anything, and I'm embarrassed to say. The negative battery cable isn't really a cable, but a woven strap. I had checked for continuity, and it seemed fine, but further investigation found it bad (see picture). I replaced the negative cable, and it starts right up again.Bad Ground Strap.jpg
 

StarTech

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Yes that cable would check fine with a meter but the area is a high resistance path to high currents. I have things like at some wire terminal where you register voltage until loaded.
 
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