Changing / checking engine oil Marcus 5of (500) thunderbolt redband

[Pipjes]

Title should say Mercury.50 bhp
..grr predictive text !!!
newbie here.. Please forgive me if I sound dim I relaying this from my husbands notes!!
We were given the above .. and we want to know how to check the engine oil ?
Husband is a vehicle mechanic so a complete novice with outboards... but we stuck on how to replace old oil as we believe this outboard has been sitting for at least 3 years .. it starts well ...

 

[galamb]

This should be a 2 stroke motor, so no engine oil - oil is premixed 50:1 with the gas on these models.

There is gear oil in the lower unit (gear case) and that should be changed. I may also need a water pump service if it's been sitting - an impeller would be minimum and perhaps a gasket/seal for the water pump cover.

Being a vehicle mechanic, with the help of a manual (a Selocs manual available at many marine places or on-line) should allow him to do all the little maintenance jobs that would be required.

But if it starts already there shouldn't be much needed.