DC Motor question

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Squisher

Lifer
Aug 17, 2000
21,204
66
91
Think of the application folks:

Starter motor pulls a couple hundred amps for a few seconds. Thus corroded wire CAN drop enough voltage across the corrosion to cause the problem.

Think how a starter motor works, and BTW - Rubycon was right the whole time.

The issue isn't in the motor. It's in the solenoid.

In order for the starter to engage, first the solenoid must actuate fully - usually there is an actual switch involved.

If the voltage presented from the battery across the corrosion were something like 11.1V (say 1.3V dropped across the corrosion) and the solenoid needs at minimum 11V to function, what would happen if the voltage dropped to 10.9V the next day? The solenoid wouldn't engage, the motor wouldn't turn, and at most you would get a series of clicks as the solenoid weakly tries to pull the gear into place. At worst it would hear nothing as the battery discharges through the closed coil without doing any work and just heats up.

This is precisely why you never really hear a 'weak starter' anymore. The solenoid gives out well before RPM of the motor is affected.

I'm not getting a series of clicks, I'm getting a definitive clunk (makes me think solenoid is engaging, but motor won't turn). Never-the-less I'm buying what you're selling, and have a new wire loom (+ and -) on order from the dealer.