It is 6hp and has no spark plug. There is a compression relief lever to facilitate hand cranking. They, Otto Hintz and his son Otto, Jr., used this engine for a long time but someone used calcium chloride for anti-freeze and left the stuff in the cooling system so that a number of holes have been eaten through the cast iron. I believe by some careful welding, reboring and a new piston, etc., it can be restored. Cylinder head and cylinder valves seem to be restorable.