150 2 stroke Yamaha

[white013]

What would make my engine start trimming up all on its own and will not let me trim back down unless I power off engine and restart then it does again.

[robert graham]

Just a guess, but maybe a bad trim motor relay. Could also be a faulty trim switch. Do you have a Yamaha Manual with wiring diagram to help? Good luck and hopefully one of our electronic gurus here can nail this down for you.Let us know what you find.

[white013]

no I do not have manual do you have diagram. thanks

[boats.net]

Probably have water in one of trim switches and need to be replaced, disconnect engine trim switch to see if still trims on it's own.