Ehh,  probably won't hurt anything.  I'd change the oil as soon as convenient.

I’m not quite sure! I’d have to look back at the files!

Well, it’s August, last in the water a year ago, so... never.

While you’re at it, you may as well replace the gear oil in the leg if you haven’t already. When was the impeller last replaced?

1.) Drain oil
2.) Refill
3.) Enjoy the water

I have a boat and I wasn’t paying attention and I added 200 ml of gear lube to the crankcase instead of engine oil. I ran the boat a little bit but not a lot. How bad is this?

Accidentally added gear lube to crankcase on boat