Tohatsu 115 hp outboard motor MFS115A ETL

Tohatsu MFS115A ETL 4-stroke outboard motor

This engine has a displacement of no less than 1995 cc, giving this completely newly developed engine a very high torque.

Test by boote-magazin.de:
Significantly more thrust: by changing the exhaust manifold in the new model series, Tohatsu has managed to generate significantly more torque in the lower RPM range.

In the outboard motor market, it is difficult to distinguish your product too much from the competition. Of course, in the major BOOTE comparison tests, we always point out strengths and weaknesses in terms of consumption, noise level, and acceleration. The latter is measured by the time taken to reach a certain speed, and the results can differ by a few seconds. But outboard motors with the same performance otherwise look very much alike. None is noticeably stronger than the other, none particularly weaker.

When developing the new engine series between 75 and 115 hp, the Japanese manufacturer Tohatsu set its main goal to stand out from the market. But how? Should the new engines be even more economical or even quieter than those of the competition? Economical and, of course, quiet. Above all, the new engines should have the highest torque in their class across the entire RPM range and reach their top speed the fastest.

At the same time, the developers wanted to set aside the old rule that "displacement is nothing but displacement" – because more displacement would mean it would become significantly heavier, and weight is always a disadvantage. So they asked themselves how they could increase the engine's power without increasing the displacement and found another way: "Why not design an exhaust manifold that has never been used on an outboard motor before?"

The task of an exhaust manifold is to discharge exhaust gases as efficiently as possible. If a manifold is well-designed, it can significantly improve performance, especially in the lower RPM range. Tohatsu calls the result of this long development process "4-2-1 Performance Tuned Exhaust," a geometrically optimized exhaust system. Instead of merging all four exhaust manifolds into one exhaust pipe as is customary with the 4-1 concept, the exhaust ports of cylinder 1 (top) and 4 (bottom) and those of cylinders 2 and 3 are first merged into two exhaust pipes. These two exhaust pipes then merge into a common pipe. A concept that has long been known in the tuning scene for older cars, but is very unusual for outboard motors in this form.

Merging according to the 4-2-1 method with exhaust pipes of exactly the same length creates a suction effect that intensifies the exhaust gas flow from the engine. Simply put, the pistons do not have to struggle to push the exhaust gases out through the valves first; a negative pressure supports them. In practice, this simple but intelligent modification ensures impressive acceleration behavior and the engine actually reaches its top speed faster.

We tested the new 115 hp model on the Elbe and were impressed by the power control, especially in the RPM range between 3500 and 4500 rpm. The high torque is clearly noticeable there. Acceleration feels different from anything known from four-stroke engines of the same size: the boat lifts its bow for a moment, then drops back down and literally starts to run. The test boat, a Valiant V-570 RIB, reaches a speed of 50 kilometers per hour after 6.7 seconds and continues to accelerate without significant reduction to a top speed of 72 kilometers per hour with the Tohatsu 115 hp.

Tohatsu has even managed to meet all the specifications it set for itself: the Tohatsu MFS115 AETL is well below or in the middle of the field between the Yamaha F115 (2.1 l, 163 kg), Yamaha F115B (1.8 l, 177 kg), Suzuki DF115A (2.0 l, 187 kg), and Honda BF115 (2.3 l, 220 kg). Tohatsu offers the best torque-to-weight ratio. Due to the small displacement, the Tohatsu engine is also extremely economical. In the engine RPM range between 3000 and 3500 rpm, it consumes only 0.32 or 0.35 liters of gasoline per kilometer, giving it a theoretical range of 304 kilometers (fuel tank capacity: 100 liters) when cruising efficiently. At full throttle, the engine requires almost twice as much fuel (0.62 liters/kilometer), which is also perfectly fine by comparison.

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Speeds

• With a Gemini WR550 RIB with 350 kilograms of boat weight, you sail with a 115 hp outboard motor at a maximum speed of 80 kilometers per hour.
• With a Ryds 630 VI Sport with 690 kilograms of boat weight, you sail with a 115 hp outboard motor at a maximum speed of 74 kilometers per hour.
• With the Reitdieper 730 Tender Sloop 7 meters with 870 kilograms of boat weight, you sail with a 115 hp outboard motor at a maximum speed of 57 kilometers per hour.

Water Displacement
According to a rule of thumb, for fast-planing boats, you need 1 hp for every 10 to 20 kilograms of total weight. Based on this, this outboard motor is suitable for 1 to 2 tons of total weight.
For displacement hulls, 1 hp per 150 kilograms to 200 kilograms is sufficient; then the engine is adequate for 17 tons to 23 tons of total weight.

Tohatsu 115 HP outboard motor MFS115A ETL
The design of the MFS115 is based on the best-selling models, the MFS40 / 50/60 and the MFS9.9 / 15/20. The legacy of the best-performing and most reliable engines has been passed on with a dynamic design and refined details to our all-new MFS115 4-stroke outboard motor with the first innovative features in the industry.

The groundbreaking technology, the 4-2-1 Performance Tuned Exhaust, provides unparalleled torque across the entire RPM range. The higher the torque, the better the hole-shot, which translates into higher speeds. Higher torque also means less resistance, which in turn means more sailing options; it can be applied to any type of boat. From light to heavy, recreational or professional use.

The synergy between the 4-2-1 Performance Tuned Exhaust and our precisely tuned ECU programming, MFS115 offers strong acceleration when needed to get the boat on plane faster and enable you to reach top speed faster.

Equipped with standard features such as a Variable Idle System that allows you to change the idle speed from 650 to 850 rpm, a low gear ratio (2.08:1) giving you the higher torque at low RPMs that your boat needs, a freshwater flushing system designed to simplify routine flushing, and a powerful 41-amp alternator, the MFS115 offers the industry-leading features you expect from Tohatsu.

Standard features include:
• Variable idle system to adjust idle speed from 650 to 850, in 50 rpm increments, for better trolling control
• Low gear ratio (2.08:1) provides low-end torque and better top-end performance
• Freshwater flushing system designed to make routine flushing easier

SPECIFICATIONS

• Power 115 hp
• Lubrication: 4-stroke
• Weight 178 kilograms
• Starting: Electric
• Steering type: Remote control or tiller handle
  
• Gear shift: Forward - Neutral - Reverse
• Fuel system: Injection
• Number of cylinders: 4
• Displacement 1995 cm3
• Maximum power 85 kW
• Wide open throttle range: 5150-5850 revolutions per minute
• Bore × stroke 84x90 mm
• Trim/tilt method: Power trim - Manual trim/tilt
• Shaft length: L (20'' = 51 centimeters)
  
  

At Marinaut, this includes:

• Rigging cord kit B standard vertical mounting panel without switch box/remote control (part number 3YU-84556-1).
• • tachometer*
  • trim gauge
  • wiring harness
  • ignition switch
  • kill switch
  • communication cable kit.
    
    
  • or on request Side mount kit B Side-mount switch box with mounting kit, tachometer, trim gauge, wiring harness with ignition switch, kill switch and communication cable kit (part number 3UH-84555-1).
    
    
  • Trim gauge* (2" diameter) shows the angle of the engine for optimal performance and efficiency. Features a domed lens to minimize glare in direct sunlight, a fog- and scratch-resistant coating and chrome bezel.
  • Tachometer with a range of 7,000 rpm (10 cm diameter) features a chrome bezel and is illuminated for good visibility in the dark. Features a domed lens to minimize glare in direct sunlight and a fog- and scratch-resistant coating. The tachometer informs about possible problems, such as low oil pressure, low battery, and overheating, via built-in warning lights.
  • propeller aluminum with 3 blades and hub kit (connection between the propeller and the propeller shaft) aftermarket*.
    • 24-liter fuel tank with fuel hose with primer bulb, aftermarket (55 liters surcharge €195
    • Engine oil

    • Delivery inspection.
      The included aftermarket aluminum three-blade propeller and hub kit, the 24-liter fuel tank with fuel hose and primer bulb, engine oil, and delivery inspection have a combined value of €475.

• *or propeller OEM Tohatsu aluminum with 3 blades and hub kit Surcharge €419.

  Available propeller sizes:

	Water displacement	Diameter	Pitch			Article number
	Light	13.2	21			3HKB64545-0
	Light	13.2	19 (most supplied)			3HKB64541-0
	Average	13.3	17			3HKB64536-0
	Average	13.5	15			3HKB64532-0
	Average	13.7	13			3HKB64527-0
	Heavy	14	11			3HKB64523-0
	Heavy	14	9			3HKB64518-0

BENEFITS

• Dynamic design with refined details
• Exciting sailing performance
• Superior durability and optimized weight
• Excellent fuel consumption due to unique SOHC-4V design
• Performance-inspired engine sound and the quietest at idle
• Tuned ECU programming
- Available in long (20”) & ultra-long (25”) shaft lengths

High performance and easy operation

• 4-2-1 Performance Tuned exhaust generates high torque to get you on plane faster
• A precisely tuned ECU ensures strong acceleration when needed
• Electronic fuel injection
• Microcomputer-programmed ignition system for faster starting
• Powerful 41-amp alternator
• New and improved gearcase with wider splash plate and anti-ventilation plate
• Adjustable steering friction and trim tab for less steering effort
• Power trim and tilt

Fundamentals for user-friendliness and reliability

FEATURES

4-2-1 Performance Tuned Exhaust
Isometric aggregate exhaust manifold "4-2-1 Performance Tuned Exhaust" maximizes torque and acceleration performance. This unique design is an industry first and can only be found on Tohatsu outboard motors. By designing each exhaust passage to be of equal length, merging the exhaust of each cylinder creates extra suction that helps pull the exhaust out of the engine. This completely eliminates the possibility of exhaust interference and dramatically improves performance.
Video with details available on this page.

Excellent torque
Of the 4-2-1 Performance Tuned exhaust, the MFS75/90/100/115 has the highest torque, allowing you to get on plane faster and reach top speed faster than any other competitor.

Data based on research conducted and collected by the Tohatsu Engineering Department

Superior durability and optimized weight
For high durability and weight reduction, Tohatsu has optimized every relatively heavy component, such as cylinder head, exhaust manifold, engine base, oil pan, lower unit, etc. A special anodized process has also been used on all major aluminum components for longer engine life.

Excellent fuel efficiency
MFS75/90/100/115 has a unique SOHC-4V design in its class, where competitors are either SOHC-2V or DOHC-4V. Spark plugs are strategically placed in the center of each combustion chamber for the most efficient combustion with optimal heat conduction, resulting in strong operation and fuel efficiency.

Quiet engine
With the equal-length intake manifold, the 4-2-1 Performance Tuned exhaust, and the precisely tuned ECU, the MFS75/90/100/115 delivers an exciting and performance-oriented engine sound. Also within the high-capacity Idle Port, sounds reflect off each other to dampen the exhaust flow, which contributes to the lowest noise at idle.

Maneuverability
With its refined ECU programming, the MFS75/90/100/115 is designed to improve acceleration when needed to get the boat on plane faster. When you give full throttle, the ECU recognizes this and fires in all four cylinders simultaneously. At the same time, the ECU optimizes and delivers sufficient air and fuel, making the air/fuel mixture more suitable for rapid acceleration to generate higher torque. The higher the torque, the stronger the acceleration you get, resulting in improved hole-shots and thus faster planing. The upper and lower mounts and the gearcase have also been optimized for direct steering response and maneuverability and greater stability.

Option: TOCS 4.3-inch LCD color display with information about:

• Engine speed
• Engine operating temperature
• Battery voltage
• Fuel consumption
• Tilt/trim gauge*
• Total engine operating hours in hours
• Total fuel consumption
• Fuel tank level(s)
• Current consumption
• Course/speed
• Various warnings
• Self-diagnosis system

With NMEA 2000, J1939 CAN Bus and connection.

It is also possible to order a package of original Tohatsu analog built-in gauges for the same price; tachometer, speedometer, hour meter, trim gauge, voltmeter, and fuel gauge.

WHY TOHATSU