Hi I have got an out board motor (seagull forty plus, if that makes a
difference) that works fine but annoyingly has no electric cut off
switch.
Does this have mechanical 'points' or some electronic ignition module?

You should be able to easily short a low-voltage control point (shorting
across points is typically done), for a Kill switch. If you make it a
momentary switch like many lawn mowers, you won't have to remember to
turn it on again.

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Regards, Terry King ...In The Woods In Vermont

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