Comments by "Mikko Rantalainen" (@MikkoRantalainen) on "See Thru Starter In Slow Motion" video.

  1. Great work demonstrating this kind of old school starter. The ingenious part of this design is that if the gears do not mesh, the starter motor will not be connected to electric power at all. All the spinning of the pinion gear is just springs inside the mechanism that gets pushed by the solenoid. Some pinion gears have some kind of forced release mechanism in case the solenoid hangs while in starting position. If the pinion doesn't release, the engine will spin starter motor too fast and the coils in the anchor will be thrown away by high g-forces. That will typically destroy the starter and may take the teeth from the flywheel, too. I think the video would have been more interesting if you had included info about what can go wrong and what happens then. The most common failure mode for the solenoid is facture in the fork that tries to connect the solenoid to the pinion because the spring in pinion is supposed to pull the solenoid away from the contacts.
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