Marine Engine/Drive Variations
The AERA Technical Committee offers the following information regarding marine engine/drive variations.
There are two basic types of sterndrive arrangements.
"A" The engine is mounted inside the boat. The transmission/drive unit is
outside, attached to the transom. Power is transmitted via a coupler and
"B" The engine and transmission are mounted inside the boat. The drive unit is outside, attached to the transom. Power is transmitted via a typical clutch and pressure plate assembly, which is electrically actuated. Clutch actuation occurs automatically when shifting, and requires no attention from the operator of the boat.
The engine and reverse gear (transmission) are mounted inside the boat. A propeller shaft is connected to the reverse gear (transmission) and is run out of the hull through a shaft log with packing gland. With this type of drive, the engine can be installed with the flywheel facing forward or aft.
This is a modified inboard installation. The engine is mounted with the flywheel forward. The V-drive is mounted to the flywheel end of the engine facing forward. A propeller shaft is connected to the rearward facing end of the V-drive and is run out of the hull through a shaft log with packing gland.
The engine is mounted inside the boat with the flywheel end aft. A high speed pump is connected to the engine. The pump draws in water through an intake grate, increases its velocity and forces it out through a directionally adjustable nozzle, which is mounted outside the boat.
The AERA Technical Committee