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CRANKSHAFT.

The crankshaft is in one piece of exceptional stiffness. It is supported by roller bearings everywhere. The propeller thrust is taken by a single thrust race, so mounted that it absorbs thrust in either direction. The patented system of double oil circulation cools the crankshaft and big end.

LUBRICATION.

The lubrication is on the dry sump principle. Any excess of oil is collected in an extension at the bottom of the crankcase and pumped back to the tank through a filter. The pressure pump delivers oil to the hollow crankshaft which is drilled with a double system of holes, out and return, so that the oil circulates from the front to the extreme back and to the front again, where it is freely delivered to the timing gear. This system not only keeps the crankshaft and big ends cool, but makes the lubrication of the crankpins absolutely sure, as the oil is supplied to them from the out and return lines. A second filter is inserted between the pressure pump and the crankshaft. Both oil pumps and filter are mounted in front of the engine and are consequently quite accessible.

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