Mercury 9.9 hp standard pull start 4 stroke 209cc year 2006

by Mark Hensh
(Norwich, Norfolk, UK)

Mercury 9.9 hp switch

its a very reliable, fault free engine with few hours until day before yesterday when it wouldn't start. No spark and fault finally traced back to the sealed magnetic "Run Stop" toggle switch. This looks like a $2 toggle about 1 cubic inch of totally sealed black plastic with a red plastic toggle on the front which can accept a lanyard "kill" which will actually just flip the toggle to "stop" if it's jerked off by the operator. A simple on off toggle switch wont work for some reason on this circuit, so for the moment I've disconnected the earth to ground wire to allow easy starting once more and I manually ground that lead when I want to stop the engine. Not ideal and I'm looking for a simple switch that will do the job as I refuse to pay Mercury the £54 they want for something that will still give them a good profit if they sell for a tenner. I finally managed to find a circuit diagram and schematic for this engine yesterday and the circuit shows a magnetic stop switch. No details such as normally off normally on", no power and powered resistences etc but I've seen much more complex and well made switches which IF somebody could tell me about the Mercury switch data, would do the job for a much more reasonable price. Any ideas please?