These engines are usually to be found fitted onto ride on lawnmowers and garden tractors.

They are overhead valve and will have a rocker cover with the letters OHV cast or stamped into the front. The spark plug will be set fairly deep and to the side of the rocker cover.

This series of engines are usually to be found on ride on lawnmowers but can also be found on industrial walk behind mowers, paddock cleaners (poo pickers) and other equipment.

They have side valve (L-Head) configuration with the spark plug near the centre of the cylinder head.
The head is flat with vertical cooling fins and often has a flat, pressed steel cover plate over most of the fins
with a hole for spark plug access