Small Engines (Lawn Mowers, etc.): Electric shut off switch for two honda gx 160, honda gx 160, sensor wires

Question
I have a pump system that uses two gx 160. each has it's own shut-off switch. I want to wire these together so one switch shuts off both motors. There is a small oil minder on each and one yellow wire going to the factory switch on each motor. This should be fairly easy but I'll be darned if I can get it to work the way I want it to.
Thanks,
Bob

I cut each yellow, spliced both to one side of a switch and then added a wire from the other side of the wsitch to ground. Should be simple make or break but I geuss not.

Answer
Make sure that the low oil sensor wires stay intact or they won't operate independantly.
Check for continuity between ground and your wires on the switches.
Connect the ground wires for each engine together and then connect the other 2 wires together.
Now hook up the grounded wires to one side of the switch and the other wires to the other side.
Check for continuity before starting.
Let me know what happens and we can go from there.
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