TOPIC: BEWARE the Aftermarket Pinion Nut (Driveshaft)

Evinrude part number 310422. Down in the gearcase it hold the pinion gear onto the driveshaft on 60's era larger Starflites.

I ordered a new one of these and what arrived was a thin nyloc nut. I used it, torqued it correctly and closed up the gearcase.

Last run of the year I was headed back to the dock when the engine started making a very ugly metal on metal sound and would not shift out of forward.

Long story short, the aftermarket pinion nut is thicker than original and was being ground down, it picked this weekend to start shedding sizable pieces. Prior to this there were no noticeable metal flakes in the oil.

Good news is I have another lower waiting for me to find why the reverse wire has no continuity, but otherwise good condition.

But this aftermarket nut did a real number on the gearcase, reducing it to emergency use only status.

Not sure how the nut could have caused that. If it was actually too large in some way you would have found out much sooner. Looks to me like a gear lost a tooth...

Was the shimming of pinion gear checked ???

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Nut looks OK to me.