Nasty gear!  From the pictures it looks like you got a rough cut gear without the finish grind. Too much metal. You can compare the profile of the bad gear to a good gear by using three pins (similar to thread gauging) and a micrometer.

The bad news is that I don't think your investigation is over. How does the mating gear look? Is it worn as well? Was the bad gear hardened? At a minimum you should inspect the replacement gear at 25, 50 and 100 hours.

If you send me the bad gear and a good gear I can compare their profiles and hardness in our metrology lab.

Until you are sure of the cause of the problem you don't know if the pin is still in the hand grenade.

Brent,

 

Thanks for the offer, I just may send them to you after I talk to E-Mag folks.  You may be right about a tad too much metal in the teeth.

 

The grenade is safely on the bench.  Thus, the good news is that there is no further personal danger to me or the engine since the mag holes are now covered and the electronic ignition timing is accomplished by sensing magnets imbedded in the aft face of the flywheel on about a 4 inch radius.  A better and more accurate scheme for the dual EI systems without having to deal with synchronizing pulses or unequal gear lash.

 

I have no future use for the mag driver gear teeth so I did not examine them. I don't remember which (left or right) drive I took the bad driven gear out of since I didn't notice the problem until I removed the gears from the Hall sensor modules.  However, the driving gear either previously drove the good one or the good impulse coupler gear (sent away with the old LASAR mags) for over 220 hours without damaging them.