Abstract: An air-cooled, reciprocating piston, internal combustion engine has at least two adjacent cylinder barrels with a plurality of cooling ribs lying substantially perpendicular to the longitudinal axes of the barrels on at least part of the periphery thereof. The intake ports of the cylinder heads are located on the cooling air inlet side while the exhaust ports are located on the cooling air outlet side, and an air deflection cover overlies the cylinder barrels on the cooling air outlet side. The cylinder barrels are provided on the cooling air outlet side with cooling ribs lying substantially parallel to the longitudinal axes of the cylinder barrels. The air deflecting cover is of a configuration such that at least some of the cooling air flowing, in the area adjoining the crankcase, around and between adjacent cylinder barrels, is deflected toward these parallel lying ribs, so that essentially the total flow of cooling air supplied may be used to cool the hottest area of a cylinder barrels.

Abstract: A hydrodynamic power transmission unit is constructed with cylindrical bearings positioned in the annular space between the outer hollow driver shaft and the concentrically disposed inner driven shaft and flow channels are provided to not only supply lubricating oil to the cylindrical bearings independently of the drive fluid supplied to the impeller and turbine discs but also to remove the spent lubricating oil in a way that it does not mix with the drive fluid. The resultant transmission unit, which can be used as a clutch for driving the cooling fan of an internal combustion engine, is more reliable and less expensive than prior art transmission units, and less noisy.

Abstract: An air-cooled, reciprocating piston, internal combustion engine which includes at least one cylinder head which includes inlet and exhaust ducts having inlet and exhaust valves with stems, the stems extending parallel to one another, said valve stems being oriented with respect to a longitudinal axis of the engine such that a plane passing therethrough will lie at an acute angle to the longitudinal axis of the engine. The external walls of the cylinder heads which provide the inlet and exhaust ducts, together with a central area arranged between the ducts, form, in the cylinder head section facing away from the cylinder, at least one arcuate or S-shaped cooling air duct when positioned adjacent a similarly constructed cylinder head.

Abstract: A reciprocating piston internal combustion engine having a plurality of heads, a glow plug associated with each one of the pistons, a source of DC voltage, and a control for providing heating power to the glow plugs. The engine also has engine oil and transmission oil flowing therethrough, and a fan for cooling the oil. A first switch turns the fan on and off. There is included a central electronic control which includes thermistors for sensing a temperature related to the temperature of the engine and for providing a connection from the source of DC voltage to the glow plugs when the sensed temperature is below a predetermined value and for disconnecting the source when the sensed temperature is above the predetermined value. A duty cycle rate generator alternately connects and disconnects the source of DC voltage to the glow plugs above the preset value at a duty cycle rate which ranges from 0 to 100 percent and which depends on the voltage level of the source of DC voltage.