Skipper’s Outboard Motor Guide is a convenient lie-flat water (and oil) proof reference to all types of outboard engine.
There is advice on how the engine works, how each part interacts, dos and don’ts, fault-finding and troubleshooting tests, all illustrated with detailed exploded diagrams to show how to fix problems.
There is advice on: Oil systems, Cooling, Gears, Plugs and points, Circuits, and, Electrics.