Any vessel that is driven by machinery of any kind is a 'power driven vessel' as defined by the International Regulations for Preventing Collisions at Sea. A motorboat is a vessel featuring a jet pump of propellor that is driven by an internal combustion engine. They vary greatly in size from small 4 meter vessels to vast luxury yachts.
An engine that is installed inside the boat is called a powerplant.
A removable engine attached to the boat is known as an outboard motor.
Outboard Motors
This motor in this type of vessel contains the internal combustion engine, gear reduction / transmissionand the propellor. It is installed at the rear of the boat.
Inboard / Outboard Motors
These are a combination of powerplant and outboard features. Like the outboard motor, the engine is contained inside but the gear reduction and propellor are on the outside.
Inboard Motors
The shaft and the propellor are the only external elements of an inboard boat. There are two types of inboard configurations: v-drive and direct drive. In a direct drive, the powerplant is mounted near the middle of a vessel whereas, in a v-drive, it is at the back of the boat facing backwards.
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