Japanese engine manufacturer Tohatsu is presenting its new MFS150A outboard motor at boot Düsseldorf. The model delivers 150 hp and is designed to score points with its low weight. Tohatsu claims that the engine is up to 60 kilograms lighter than competitor products in this power class. This is achieved, among other things, by an intake manifold made of high-performance plastic instead of metal. The intake manifold guides the fuel-air mixture from the carburettor to the cylinders.
Engine design and technology
The MFS150A works with an overhead camshaft and four valves per cylinder. The camshaft controls the opening and closing of the valves. With an overhead design, it sits directly above the valves in the cylinder head. According to the manufacturer, this design is intended to improve fuel combustion and optimise heat dissipation. Tohatsu has developed a new camshaft and valve system for this model that is specially adapted to the engine.
Performance data and consumption
According to the manufacturer, the MFS150A achieves a five per cent higher top speed than previous models. Acceleration is said to be two per cent faster. At 2,000 revolutions per minute and fully open throttle, the engine consumes 15 per cent less fuel. These values are based on measurements taken by the manufacturer. According to Tohatsu, this means more agile handling and lower operating costs for boaters.
Noise development
Tohatsu claims that the MFS150A is significantly quieter than comparable engines. At idle, the noise level is said to be up to 34 per cent lower than that of competitor models across all frequencies. A newly developed idle control valve and a modified throttle valve are responsible for this. The idle control valve controls the air supply at low engine speeds and ensures that the engine runs smoothly.
Exhaust system
The engine utilises a 4-2-1 performance exhaust system. This designation describes the structure of the exhaust system: four cylinders first lead to two manifolds, which then flow into a common tailpipe. This design is intended to prevent exhaust interference. This refers to disruptive pressure waves that occur when exhaust gases from different cylinders influence each other. The system is already used in the Tohatsu MFS140 model.
Design and colour variants
Visually, the MFS150A differs from previous Tohatsu models. The manufacturer has added three-dimensional side stickers and changed the rear design. Buyers can choose between two colours: Aquamarine Blue and Beluga White. The motor is available in different shaft lengths. The shaft length determines how low the propeller sits under the boat's transom. Tohatsu also offers a counter-rotation version. In this version, the propeller rotates in the opposite direction, which is intended to improve the handling characteristics in multi-engine installations.
Technical data
- Performance: 150 HP
- Weight saving: up to 60 kg compared to competitor models
- Valves: 4 per cylinder
- Camshaft: overhead
- Consumption reduction: 15% at 2,000 rpm (manufacturer's specification)
- Acceleration: 2% faster (manufacturer's specification)
- Maximum speed: 5% higher (manufacturer's specification)
- Noise reduction when idling: up to 34% (manufacturer's specification)
- Exhaust system: 4-2-1 performance system
- Colours: Aquamarine Blue, Beluga White
- Availability: Various shaft lengths, optional counter rotation
Jan-Ole Puls
Editor Test & Technology
