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An Overview of Kerosene Outboard Motors An Alternative Energy Outboard

yamaha kerosene outboard

A fleet of Kerosene-fueled outboard fishing boats in Asian waters head out to sea.

Learn how Kerosene Outboard Motors Power Small Fishing Boats in the Third World

Depending on where you live in the world, you may or may not know about kerosene outboard motors. These bi-fuel motors are popular in the third world, mainly in Asia, where governments significantly subsidize the price of kerosene.

The reason for this fuel subsidy is because kerosene, also known as home light oil, is used for cooking and for lighting. In India the subsidized price is about 15 cents a gallon with the intent of discouraging the cutting of wood for cook fires (deforestation). So cost is about 1/3 the price of gasoline in places like Thailand, Sri Lanka and India. Kerosene motors are bi-fuel. Which is to say they start up on gasoline and then transition to kerosene once engine temperature is high enough to vaporize the kerosene so its fire can be lit with a sparkplug.This is not new technology. In fact it dates back to the 1930s.

Yamaha kerosene outboards on the beach in Asia

Yamaha Marine kerosene-outboard fishing boats pulled up on an Asian beach

Kerosene outboards cost less to operate than gas outboards, but are not without their problems.

Kerosene outboards are better suited for trolling or long hauls, rather than for short trips. Because kerosene burns at a higher temperature than gasoline and combustion is not as efficient, exhaust smoke is copious and quite stinky. Kerosene outboard longevity is reduced to only about half that of its gasoline counterpart. Kerosene outboards are carbureted, two-stroke outboard motors with power ratings from 9.9-horsepower to 40-hp. Which means they mix two-stroke oil with both their gasoline and kerosene fuel.

Kerosene outboards listed by brand name and horsepower
Horsepower 8 9.9 15 18 25 30 40 55 185
Yamaha * * * * *
Suzuki * * * *
Tohatsu * *
Evinrude *
Mercury Racing *
yamaha kerosene ouboard motor

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