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Tohatsu Direct-Injected
40 Horse Outboard Motor

Studio photo of Tohatsu 40hp tldi outboard

Compared to equivalent conventional two strokes, Tohatsu's 40-horsepower motor offers improved fuel economy and significantly reduced exhaust emissions.

Compared to equivalent conventional two strokes, the new 40 horsepower motor offers improved fuel economy and significantly reduced exhaust emissions. Beyond a soft footprint on the environment, its biggest claim to fame is razor sharp acceleration.

TLDI Stands For
Two-Stroke Low-pressure Direct Injection.

For those who may be unfamiliar with the technology behind the name, the acronym TLDI stands for Two-stroke Low-pressure Direct Injection. Unlike competitors Mercury, Evinrude and Yamaha, whose outboards also rely on high-pressure direct injection, the Nissan/Tohatsu direct injection method relies on low pressure direct injection.

TLDI Air Compressor TLDI Direct Injection TLDI ECU

TOP LEFT: The air compressor atomizes the fuel
TOP RIGHT: A view of the TLDI combustion chamber
BOTTOM: The electronic control unit manages engine operations

Tohatsu and Nissan Outboards Build a Mid-Range, Direct Injected Two-Stroke Outboard Motor Dubbed the 40 TLDI.

That said, just like Mercury Marine’s DI Optimax engines, Nissan/Tohatsu’s direct injection is based on the good work done by the Australian think tank, Orbital Engine of Australia. Direct injection works its magic by relying on pressure to break fuel molecules into microscopic droplets (smaller than 10 microns).The expanded surface area exposes a greater volume of the gasoline to oxygen. That makes for a cleaner burn.

Besides its new 40 horsepower model, Nissan and Tohatsu also build TLDI motors rated 50, 70 and 90 horsepower. Below 30 horsepower all the motors are four-strokes.All of the two company’s current four stroke and TLDI motors meet the stringent EPA 2006 and CARB 2007 emissions regulations. The real eyebrow raiser, the warranty term provides four years of coverage from the date of engine installation. Nissan and Tohatsu outboards are marketed in the U.S. by Tohatsu America.

Tohatsu/Nissan 40 TLDI Specifications:
Engine (No. of Cylinder) 3
Output 40 hp (29.4 kw)
Displacement 697 cc (42.5
Bore x Stroke 68 x 64 mm (2.68 x 2.52 in)
Starting Electric
Control Type Remote Control or Tiller Handle
Gear Shift Forward - Neutral - Reverse
Gear Ratio 1.85:1
Propeller Selection Range 7" - 15"
Transom Height 15", 20"
Fuel Unleaded Gasoline (87 Octane)
Oil Type Premium TCW-3
Fuel Tank Optional
Weight* 205.7 lbs. (93.5 kg)
Alternator Output 12V, 280W, 23A
Max. RPM Range 5,150 - 5,850
Direct Fuel Injection S
Inductive Ignition System S
Start In Gear Protection S
Thermostat Controlled Cooling System S
Through-The-Prop Exhaust S
Power Trim and Tilt S
Variable Idle Speed 700, 800, 900 rpm