Anyone any good with outboards?

[guindilias]

Have an old Yamaha 50 (pre oil injection, suspect late 1980s), which is supposed to be electric start. Has been sat uncovered for a few years (cowling on, but no boat cover).
Finally got it to start and run by shorting the +ve of the battery straight to the starter, but the key (Yamaha 703 forward controls) won't spin up the starter.
I presume there is a solenoid/relay somewhere that could be dead? Any advice appreciated!

[guindilias]

Well, a happy ending after all that! Went through the wiring backwards from the starter, and it turned out to be the (extremely hard to get to!) starter solenoid. £50 later and it starts first time on the key. Thanks for the help!