Inboard engine

Inboard engine means a four stroke marine SI engine that is designed such that the propeller shaft penetrates the hull of the marine vessel while the engine and the remainder of the drive unit is internal to the hull of the marine vessel.

Source

40 CFR § 91.3

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Scoping language

The following definitions apply to this part 91. All terms not defined herein have the meaning given them in the Act.

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