Engine Oil Leak on a 4 stroke

[beaker]

I've got at 2000 F80TLRY and its leaking oil down the lower cowling. I don't see any in the bottom of the engine when I take off the upper cowling. Does this sound like the oil seal at bottom of the crankshaft? Other than the oil pan gasket, what are the other seals/gaskets that could spring a leak?

No water in the oil, drained that today. I do have a yamaha manual and I'm looking for the most likely fix. I just fixed a problem with a fuel vent that allowed water in the tank twice. Could any symtoms of this cause the oil seal problems (vibration, overpressure...)?

Thanks in advance for any help.

[beaker]

I'm thinking bout pulling the power head and checking the lower crankshaft seal as well as inspecting the oil pump once its exposed. Are there any other places I should look for as oil leak paths down the lower unit?