Outboards

As well as providing propulsion, outboards provide steering control, as they are designed to pivot over their mountings and thus control the direction of thrust.

Combined with modern waterproof battery packs, electric outboards are also ideal for yacht tenders and other inshore pleasure boats.

Fuel economy on both direct injected and four-stroke outboards measures from a 10 percent to 80 percent improvement, compared with conventional two-strokes.

Historically, a majority of outboards have been two-stroke powerheads fitted with a carburetor due to the design's inherent simplicity, reliability, low cost and light weight.

Many large outboards are equipped with power trim, an electric motor on the mounting bracket, with a switch at the helm that enables the operator to adjust the trim angle on the fly.

Most available electric outboards are not as efficient as custom drives, but are optimised for their intended use, e.g. for inland waterway fishermen.

This means saltwater is not pumped through the engine block as is the case with most outboards but still has to be pumped through the heat exchanger Other Outboard Motoring Method Vietnamese-style "Shrimp Tail Outboard Motor" Schematic.