A freelance model of a horizontal open crank petrol engine as used 50 to 100 years ago to drive pumps, saw mills etc. Ignition is by small modern electronic device intended for use in model aircraft, tucked away under the engine with a magnet in the flywheel. The governor is hit and miss so that when the engine over revs the exhaust valve is held open and the automatic inlet valve doesn't open.
Very ingenious!
Manorfarmdenton 6 months ago