I have a 2005 40HP mercury outboard with an oil injection system that leaks oil when the motor is tilted up. The oil has the color of the oil that the reservoir (blue/green) is full of. Can't see anything obvious.
Check the oil tank and all oil lines for leaks. I had to replace all my oil lines because they decomposed. They looked fine but they all started leaking and if you disturbed them they would crack and crumble.
