1965 Merc 3.9hp Has a Hole in the lower casting

[Teseal]

Just finished up working on this little Merc getting ready to finial test and noticed the small hole in the lower casting just above the gear box. Anyone have any idea how, why, or what? It's such a round, clean hole can it possibly be a bad spot in the casting just rotted through?

 

[racerone]

I think they all have that hole.----Any water in the gear oil.----Has to be there to drain water from a cavity.

 

[1960 Starflite]

It is to drain water from the shift shaft area of the lower unit. Keep it open, especially in freezing areas.

 

[Teseal]

Yes racerone, I replaced the prop shaft seal because I found water in the gear box. Wasn't aware of the drain hole thx Starflite. For sure tho I will check the oil after I run it for awhile.

 

[Teseal]

Looks like its good to go, Thx to you both for your time and attention.