A follow-up on this as I finally had a chance to work on it yesterday. Been fishing too much, and just shutting the engine off by hand.
I will start with how the system works on my Yanmars which will hopefully help others who run up against this issue.
First, the Yanmar is a run without power motor, The solenoid engages to shut off the fuel. So the solenoid is only momentarily engaged, probably no more than 3 seconds at a time when shutting down.
Components in the system are:
ignition switch,
stop button
relay
and solenoid.
When the ignition switch is turned on, the wire to the stop switch is provide with 12 volts and the stop switch is “hot”. When the stop button is pushed, voltage is provided to the relay which closes and completes the circuit to the solenoid.
Also, when the ignition switch is turned on, the wire that powers the solenoid is also “hot”.
So, two wires from the switch on the dash on the bridge go all the way along the side of the boat, into the bilge area onto the port side of the motor, across the back of the motor (laying across the area just forward of the the bell housing) and finally to the relay. Probably some 25-30 ft. The relay just dangles there, behind the oil filter and very low in the bilge area. And of course there is a wire from the relay up to the solenoid, which is only about 2 feet away. Thus there is a wire from the ignition switch to the relay that is hot whenever the ignition is on.
The problem arises from that “always hot” wire to the relay always setting in a rather wet environment.
When I unplugged the relay, this one wire was badly corroded. No surprise as it is always hot. So badly corroded that the spade on the relay broke off in the socket!!
I managed to get everything fixed and all is back to stock. I can’t believe that I was able to recover the socket!
To my way of thinking, the relay should be wired as part of the dash and not setting in the bilge So a short wire from the switch to the relay and another short wire from the stop button to the relay. And a long wire from the relay to the solenoid, which is only hot when the stop button is pushed. I think Tony has a name for the type of engineering used on this motor
Another way to look at this is to let my finger be the relay. In this case I think that would be a much safer set-up than what is there now. As long as the stop button can handle the current required.
For now it is all stock and works. I can shut down from the fly bridge again.
If anyone has questions, please ask. I hope I was clear enough to be understood.
Bill F.
.
