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The system that completely obviates the need for lubrication.
The shafts which carry the spheres are supported on sealed bearings, and that's it: no oil is needed to be pumped up to the cylinder head. No fuss, no mess. The benefits are enormous, perhaps even greater than is at first realised. First and perhaps most important, valve train inertia is reduced drastically, such that there is no longer any mechanical limitation /within reason... to the valve timing and opening/closing speeds.
Safe engine operating speeds for the Coates engine will theoretically be restricted only by the mechanical limitations of the major rotating assembly (crankshaft, conrods and pistons), rather than the valve train as on poppet valve engines.
But the lack of oil in the cylinder head area is also a great advantage, as in a conventional engine some of the oil required to lubricate the valve train inevitably finds its way into the combustion chamber, to the detriment of combustion cleanliness and efficiency. Valve guides, for example, are a real problem area in modern engines as designers look to reducing running clearances in an endeavour to meet ever more stringent emissions targets.
The transfer of the rest of combustion to the cylinder head, and hence to the coolant, is also much more effective through the spherical valves, meaning that temperatures in the cylinder head and especially in the combustion chamber can be kept much lower. Ultimately this should mean that leaner mixtures can be burnt safely, and/or higher compression ratios may be utilised, to the benefit of power, fuel economy and emissions
How Does It Work. ???
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