The new engine brought out by the Dayton Motor Car Company, owing to complete changes in design and construction, is one of the most efficient and well-constructed motors on the market to-day. As can be seen from the illustration, the water-jacketed valve chambers surmount the cylinders, and form part of two integral castings. The inlet and exhaust valves are upon opposite sides, and each pair of valves is operated by a double rocker arm having a central roller bearing provided with a grease cup. Each pair of cylinders is fitted with a copper water jacket having four corrugations. The water is circulated by a centrifugal pump of generous size, which is gear-driven from the cam shaft. The shaft which drives the pump. also rotates a Bosch high-tension magneto, which is located upon a bracket at the rear of the motor, if the purchaser desires magneto ignition. The 30—35-horse-power motor shown has a bore of 4%, inches and a stroke of 5 inches. The valves are all 214 inches in diameter. The crankshaft is a drop forging of nickel steel and is offset % of an inch from the center of the cylinders. This offset gives the greatest leverage, and reduces to a minimum the friction of the pistons on the side walls of the cylin-.ders. The bearings are all positively oiled by a stream of lubricant, which is drawn from an oil well separate from the crank case proper, and is forced to all the bearings by means of a gear pump. Special oil rings fastened to the crank cheeks carry the oil which comes from the crankshaft bearings, and feed it by means of centrifugal force to the pins. The camshaft bearings are also positively oiled. The fan is mounted upon two Timken roller bearings, and is provided with a thumb-screw adjustment for tighthening the belt. The flywheel is bolted to a flange, which is forged on the end of the crankshaft. The transmission is mounted in an aluminium case formed of one solid casting, and all the bearings in the transmission are of the roller type. There is not a nut or screw anywhere in the gear box which can loosen and get into the gears. The telescoping shaft of the transmission is fitted with a long, plain, roller bearing, while all the other bearings are of the Timken type. The gears are all made of chrome nickel steel, and the shafts of a special high-carbon steel. Both the propeller shaft and the floating rear axle run on Timken roller bearings. Internal and expanding brakes are fitted on the rear wheels, and consist of steel bands lined with camel's hair belting. The internal brake bands are 2lh inches wide, and are operated by a pedal. The other brakes are operated by a lever beside the driver's seat, and it is also possible to use the motor as a brake by cutting off the ignition. By opening the auxiliary air valve, which can be done from the seat, the motor will draw in only pure air while it is being used for braking. The ordinary ignition equipment of the motor consists of a four-unit coil and storage batteries, and the magneto is only fitted in case two systems are desired.
This article was originally published with the title "The New Stoddard-Dayton Engine" in Scientific American 97, 19, 346-347 (November 1907)