"Remove lower drain plug (
"Remove lower drain plug (the large screw, not the one with the Philips head on it).
Remove top screw.
Allow oil to drain. If it there is water present or the oil is a gray milky color, then you will need to work on the gearcase seals.
Fill from the bottom plug with SAE 90 hypoid gear oil until oil runs out the top. I use a differential pump screwed to a 1 liter oil bottle. While keeping a little pressure on the oil tube/bottle, close up the top plug. Remove the oil tube/bottle and quickly replace the plug.
If so equipped, also drain the carb sediment bowl (it's a small glass bowl attached to the side of the powerhead).
Make sure the exhaust tower weep holes are free to drain (yours has at least one somewhere between the waterpump and the upper part of the gearcase).
Grease the swivel, throttle, gearshift grease points with marine grease.
Do not store your motor upside down or with weight on its skeg."