2 Stroke Engine Phase Out

Since December 31^st 2006 traditional "carburetted” 2-stroke engines have not been imported into this country, initiating a major phase out of this type of engine.  However, the ban is not retrospective so as long as your 2-stoke continues to work you can still use it! 

To meet the new emission regulations outboard companies are now replacing their carburetted 2-strokes with either a 4-stroke engines or a "direct-injection" 2-stroke.  As a result of this new technology, the new direct injection models now being produced meet all the relevant emission regulations in Europe and North America.

In addition to significantly reduced emissions, the direct injection 2-stroke models also have significantly reduced fuel consumption rates and in many cases, even better than a comparable 4-stroke model. 

Advantages of Direct Injection 2-strokes over carburetted 2-strokes

-          Significant reduction in emissions and considerable reduction in fuel consumption – save money and the environmental impact.

-          Eliminates the need for a choke giving easy and quick starts in all weather conditions.

-          A smooth, consistent idle which produces significantly less vibration.

-          Quiet and practically smokeless operation.

-          No need to pre-mix oil and fuel.

-          Consistently smooth transition from low to high speed.

Direct Injection 2-strokes vs. 4-stroke engines

-          Manufactures now have a dilemma over which engine to produce at which horsepower as both comply with the relevant emissions regulations.  Most manufacturers are taking a “two-pronged” approach and producing a combination of direct injection and 4-stroke engines depending on the horsepower of the motor.

-          The major problem with 4-strokes is weight and the heavier the boat the poorer the performance and the more fuel the boat will use.  Four stroke motors are inherently heavy due to the number of parts required compared to a 2-stroke motor.

-          TLDI® motors on the other hand use our existing and proven 2-stroke blocks and combine that with our advanced DI technology to produce a lighter, “new technology” motor.  In fact our 90 TLDI® weighs up to 24% less than competitor’s 4-stroke 90 hp motors.  This weight savings gives the TLDI® better acceleration and performance than a 4-stroke.

Direct Injection and size of outboard.

- 2-stroke direct injection is very suitable for larger outboard engines because this technology provides all of the advantages of a 4-stroke engine whilst the lighter weight gives the direct injection better acceleration and performance over a 4-stroke.

- One reason the direct injection technology is generally not applied to smaller motors is because these engines rely on electric programming to control the operation of the motor and the electronic fuel pumps. These electronics are powered by the battery and although the direct injection technology could be adapted to smaller motors, few boaters want to carry a battery when using a small motor on an inflatable boat or a dinghy.

Fuel economy of DI

The direct injection systems achieve a dramatic increase in fuel economy over conventional 2-strokes and will also provide better fuel economy than a comparable 4-stroke while travelling at cruising speeds.

References
Nissan Marine  - http://www.nissanmarine.com/tech_talk/tldi_faqs.html
Nissan/Tohatsu UK (based in Lymington)

For more information visit www.thegreenblue.org.uk