Rubber Key Boot Melted

[reelchaser]

I have twin 250 two stroke outboards on a 30ft Pursuit. One day I decided to run only one engine to catch up and equal the other outboards hour meter. For some reason one engine has two hours more than the other enginewhen I bought it.
Anyway I couldn't start the other outboard when I was ready to go back. I finally got back on one engine and reset the engine breaker. The breaker kept popping every other time we used the boat. I noticed that the key for this engine was full of black goop. I realized that the rubber key boot had melted.

Can anyone explain this and the reason that the engine breaker keeps popping every once in awhile.

Thanks for your help.

[rodbolt17]

most likly a poor ground connection someplace.
however Yamaha never set up the hull wiring and did not use breakers.
someone has monkeyed with it.
by now you may also have a bad keyswitch.
your really going to need someone skilled in electrical issues.
google yamaha outboard dealer locator.
find a dealer near you with a master tech.
if you cannot find that at least when you call the dealership make sure the tech has at least one certification on the wall for Electrical from kenesaw GA.