40 HP 2-Stroke TLDI Outboard

TLDI Model MD40

The Tohatsu 40hp TLDI® is one of the smallest engines available with air-assisted direct injection technology. This outboard has all of the benefits of new and improved 21st century technology without compromising power or performance.

We have added this new low-pressure air/fuel delivery system to our proven engine block to give you an outboard superior to al others. It provides exceptional fuel savings over 4-Strokes and conventional 2-Strokes alike and is very gentle on the environment.

If you're looking for a tiller model, we now offer a multi-function tiller handle as standard equipment. This tiller handle includes all controls conveniently located on the handle for easy access giving you more control, better maneuverability and increased safety. And our 40 hp TLDI® outboard weighs up to 15% less than competitive 4-stroke outboards and meets EPA emission regulations.

When clean, mean outboard power is what you need, look no further than the Tohatsu 40hp TLDI®.

Tohatsu 40 hp TLDI® Benefits:

  • Air assisted direct fuel injection system that provides excellent fuel economy
  • Extremely quiet operation
  • Excellent horsepower-to-weight ratio
  • Lightweight and compact
  • Available in short (15”) & long (20”) shaft lengths
  • Ultra-low emission, EPA and CARB approved
  • 5 Year limited warranty

High Performance and Easy Operation:

  • Inductive ignition system for reliable starting
  • Outstanding acceleration
  • Oil reservoir located on the top of the motor for quicker and easier refill onboard
  • Multi-point oil injection system to more completely lubricate vital engine components
  • Power Trim & Tilt
  • Remote control box**

Fundamentals for User Convenience and Reliability:

  • Through-the-prop exhaust for a quieter ride
  • Thermostatically controlled cooling system for consistent engine temperature
  • Stainless steel water pump housing liner for outstanding durability
  • High grade marine aluminum alloy that provides the ultimate protection against corrosion
  • Zinc coating on internal water passages for superior corrosion resistance
  • User adjustable idle and trolling speeds
  • Tachometer and Trim & Tilt Gauge**
  • Aluminum propeller

Warning & Protection:

  • Low oil level warning (visual and audible)
  • Overheat warning (visual and audible)
  • Battery voltage warning (visual only)
  • Start-in-gear protection for safer engine starting
  • Safety lanyard (an essential protection feature standard on all Tohatsu outboards)
  • Over-rev. limiter

** Remote control models


The TLDI® series are Tohatsu's award winning outboard motors that have an established reputation for being compact in size while demonstrating highly desired features such as low emissions and high fuel economy that are demanded by the new generation of boaters.

They are powered by a direct fuel injection system and a 32 bit ECU (Engine Control Unit). The ECU gives precise fuel injection instructions in accordance to the operating conditions detected by the multiple sensors located on the motor. The TLDI® outboard motors meets all of the emission regulations stipulated by EPA (Environmental Protection Agency) and CARB (California Air Resources Board).


Three step trolling speed control

Multi-Function Tiller Handle is available on select models. The multi-function tiller handle features an ergonomically designed shift lever for easy and convenient shifting as well as a longer throttle grip with 110 degrees rotation for easier maneuverability.

All controls on the new multi-function tiller are conveniently located on the handle for easy access and control. More specifically, the gear shift, throttle control, trim switch, safety lanyard cord, TLDI® warning lights, and electric start key switch are all integrated in the tiller handle.


Engine Control Unit Engine Control Unit (ECU)
The 32 bit engine control unit controls the fuel injection and ignition timing for TLDI® outboards.


Three step trolling speed control

Air Compressor
One of TLDI®'s essential engine components that is the driving force in achieving stabilized fuel injection.


Engine Control Unit

Direct fuel Injection into Cylinders

Due to the intrinsic design of the chamber on the cylinder head, the finely atomized fuel mist created by the fuel injector is injected near the spark plug to achieve ideal combustion.


Three step trolling speed control

Multifunctional Tachometer

The tachometer informs the operator of potential problems through the meter indicator and warning lamp. (Remote models only.)


Engine Control Unit

3-Step Trolling Speed Control

The idling speed can be set to any of the three rpm ranges, 700, 800 or 900, by adjusting it on your key switch. This feature allows you to select the ideal trolling speed for maneuvering during a variety of current and wind conditions.


Engine (No. of Cylinder) 3
Output 40 hp (29.4 kw)
Displacement 697 cc (42.5 cu.in)
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 or Recommended
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


  • S: Standard Features
  • O: Optional on Certain Models
  • * Weight specification is based on the lightest version. Specifications and descriptions are subject to change without notice.



    Parts Book Type Brand Model Book Year Book #
    Download TLDI Tohatsu MD40A 2001 002-21049-1
    Download TLDI Nissan NSD40B 2003 002N21049-2
    Download TLDI Nissan NSD40B (AQ) 2006 002N21049-3
    Download TLDI Tohatsu MD40B 2003 002-21049-2
    Download TLDI Tohatsu MD40B (AQ) 2006 002-21049-3
    Download TLDI Tohatsu MD40B2 2010 002-21048-2
    Download TLDI Tohatsu MD40B2 2011 002-21048-3
    Download TLDI Tohatsu MD40B2 2012 002-21048-4
    Download TLDI Tohatsu MD40B2 2013 002-21048-5
    Download TLDI Tohatsu MD40B2 2014 002-21048-6
    Download TLDI Tohatsu MD40B2 2015 002-21048-0AE

    Request Quote


    Prop Type Load* Diameter Pitch Blades Standard Equip. Part # Comments
    aluminum light 11 15 3   3T5B645320  
    aluminum light 11.1 14 3   3T5B645290  
    aluminum light 11.1 13 3   3T5B645270  
    aluminum moderate 11.4 12 3   3T5B645250  
    aluminum moderate 11.6 11 3   3T5B645230  
    aluminum heavy 12.1 9 3   3T5B645180  
    aluminum heavy 11.2 8.7 3   348B641071  
    aluminum heavy 11.4 7.1 4   348B641081  
    stainless steel  NA 10.25 17 3   PT4050REBP17  
    stainless steel  NA 10.5 17 3   NM889410170  
    stainless steel  NA 10.375 17 3   PT4050SCBP17 semi-cleaver
    stainless steel  NA 10.25 16 3   PT4050REBP16  
    stainless steel  NA 10.375 16 3   PT4050SCBP16 semi-cleaver
    stainless steel  NA 10.375 15 3   PT4050SCBP15 semi-cleaver
    stainless steel  NA 10.5 15 3   PT4050P15  
    stainless steel  NA 10.5 14 3   PT4050P14  
    stainless steel  NA 10.5 13 3   PT4050P13  
    stainless steel  NA 10.5 12 3   PT4050P12  
    stainless steel  NA 10.75 11 3   PT4050P11  

    Repair Kits/Electrics

    Part Number Description
    3T5-87322-3 Water Pump Repair Kit (MD40/50)

    Fuel Tanks + More

    Part Number Description
    3B770-2004M Fuel line hose (primer bulb assembly & fuel connectors)
    3FF70-2004M Fuel line hose (no connectors/fittings; fits all models)
    3B2-70260-1 8mm (5/16") fuel connector (engine male) - TLDI 40-90B
    3B270-2501M 8mm (5/16") fuel connector (engine female) - TLDI 40-90B
    99999-37851 Tohatsu Water/Fuel Separator Kit (includes one filter)
    99999-37801 Replacement 10 micron filter (for Tohatsu Water/Fuel Separator)
    99999-UF10K UNIKAS UF-10K Water/Fuel Separator Kit (includes one filter)
    99999-UF10RF Replacement 10 micron filter for Unikas UF-10K (includes replace o-ring)