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rotorwrench · 12-13-2021, 10:48 AM

The starter engages the bendix as soon as it starts to turn. The centrifugal force with the spiral teeth on the gear shaft pushes it into the ring gear. The solenoid only functions the starter motor. When the engine fires, it can kick the bendix back out prematurely. Now it is normal for the bendix to kick out when the engine fires but if the engine has a fuel delivery problem, a weak spark, or a vacuum leak that can't carry it though the start cycle after the bendix has already been disengaged then the starter will overrun the bendix and you have to wait till it stops turning before another start attempt. If everything is working well with the engine then it will complete the cycle with a lot more reliability.

On 12-volt, it just turns a lot faster. It can still disengage prematurely though.

12-13-2021, 10:48 AM	#12
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,440	Re: Solenoid disengages gear prematurely The starter engages the bendix as soon as it starts to turn. The centrifugal force with the spiral teeth on the gear shaft pushes it into the ring gear. The solenoid only functions the starter motor. When the engine fires, it can kick the bendix back out prematurely. Now it is normal for the bendix to kick out when the engine fires but if the engine has a fuel delivery problem, a weak spark, or a vacuum leak that can't carry it though the start cycle after the bendix has already been disengaged then the starter will overrun the bendix and you have to wait till it stops turning before another start attempt. If everything is working well with the engine then it will complete the cycle with a lot more reliability. On 12-volt, it just turns a lot faster. It can still disengage prematurely though.