Roberts 4X In-line 4 Engine

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Roberts 4X In-line 4 Engine

The Model 4X engine was built by the Roberts Motor Company of Sandusky, Ohio. An important design objective was light weight, which was achieved through the extensive use of aluminum and magnesium alloys in the cylinders and crankcase, and a hollow crankshaft. This engine was manufactured in 1911 and powered a Curtiss-type, float-equipped aircraft (hydroplane) built by Harry H. Ford.