I have a 9.9 mercury outboard motor 1995 I think. After winter I took it out of the boat house to get it ready for summer. My problem is when I was moving the motor around by hand I seen some gear case oil come out from a hole just to the left of the top gear case oil screw. The gear oil didn't come from the screw itself, so I'm wondering what this hole is for? Is this suppose to be a plug or something like that in this hole. My thinking is that this hole would be under water and to me that would mean water would get in and ruin the gears. Can anyone tell this DIY person what this is for and do I need to buy a part for it. Thank you for anyone taking the time to answer this. Ron in Mississauga Ontario Canada.
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