I have a 'stop' and 'off' switch to cut off the fuel in a Yanmar 2GM diesel. The 'stop' switch has failed to work. How do I determine if it is the switch or where the problem is? I need to go below and manually stop the fuel pressing the plunger on the solenoid. I had the start button on this same panel fail to the tune of $147 just for the replacement rocker switch. Is the Yanmar type 2 panel just junk?