flywheel and starter not cooperating

[bones66]

so i was having a hard time starting my truck recently and then it finally died. i pulled off the starter and lo and behold the starter and flywheel teeth were ground way down. does anyone know why this would be happening and what i should do to prevent this happening again?

 

[Anime]

Could be either from just holding the key too long when starting, or an electrical issue such as the starter or fender solenoid engaging the starter longer than necessary.

If the starter still works, just a new gear drive on it would be an inexpensive fix (possibly rebuilding and putting in a new brush assembly while you're at it), perhaps replacing either or both solenoids as well.

Otherwise if a new starter goes on and fixes the problem, then it was likely the starter mounted solenoid or just an issue with the starter motor.

If you do go new, or even if you just replace parts, you may want to check the starter every so often to see if it's getting the teeth chewed up, though if the flywheel is in really bad shape, it might chew up the starter gear just from normal contact when starting.

 

[Roadrunner777]

A failing starter can do this, if it is not retracting the drive gear correctly after start. A new starter fixes the cause. I don't know what the criteria is for replacing the flex plate/ring gear that has been worn like this.

 

[safn1949]

Also starter alignment,it might need to be shimmed.That was a big problem with GM cars when I worked on them.