Here is at translated description of the engine casting set etc.
This model engine is a model-like replica, the engine that Karl Benz installed in his first motor car in 1886. This is a water-cooled single-cylinder, four-stroke engine with intake valve. The exhaust takes place via an exhaust valve inserted in the cylinder head. The slide as well as the outlet valve are driven by a control shaft. The motor vehicle was driven by a pulley, also wedged on the control shaft. The dimensions of the engine correspond to a scale of approx. 1/3. This model engine is for operation with commercially available mixed gas
(Propane / butane). As in the original, the cooling takes place with water, which circulates in the cylinder due to the temperature difference. Due to its small cooling surface, the engine is not designed for higher speeds in continuous operation. The cast part set of this model motor contains 7 unprocessed cast parts in cast aluminum and gray cast iron, one piece of cast round for the liner and the drawing documents.
Parts still required for assembly such as piston rings, spark plugs, ignition coils and etc. can be found under "Engine accessories" and can be ordered at the same time. The price nominated on the web site is 290Euro plus postage
From JohnSamphier member.