The water cooled aircraft engines maked before second war had welded thinn steel sheet as water jacket around the cylinder and there was not dismantable cylinder head also the cylinder head was welded to cylinder, let us say the cylinder was complete with cylinderhead and water jacket to save weight. Crank shaft and cam shaft was hollowed, the crankcase was maked light as possible.

Your engine are stationary engine or marine engine, best as slow running engine, maybe not more than 1000-1500 rpm. Puf-puf-puf..