PRODUCT INFORMATION FOUR-STROKE / Electronic Fuel Injection

Suzuki’s Award Winning Technology The product of unrivaled expertise and world class technology, Suzuki’s four-stroke outboards have long been on the cutting edge of outboard performance winning acclaim and awards for their advanced technology, innovative ideas, and designs. We were the first to introduce a digital Electronic Fuel Injection four-stroke; an idea that allowed the DF60 and DF70 to receive further recognition from the International Marine Trades Exposition and Convention when they captured the IMTEC Innovation Award. We were the first to offer an automotive type self-adjusting timing...

s "The Ultimate" DF250 Relying on experience we’ve gained through the manufacture of not only outboards, but technologically-advanced motorcycles and automobiles, our engineers have put decades of knowledge into the design, development, and production of an all new V6 motor designed specifically for outboard use. This new V6 holds some of our most advanced innovative ideas to date, making it a showcase for Suzuki’s advanced four-stroke outboard technology. The flagship DF250 is the industry’s first 250PS (184kW) V6 four-stroke outboard and the most powerful outboard ever built by Suzuki. Its...

s The Ultimate in Performance Torque Curve DOHC 24-Valve with VVT Delivers High Performance Our engineers designed a 3.6-liter V6 engine—the largest displacement found in the industry thus far—and an aggressive cam profile designed specifically for the DF250 to create the industry’s first 250PS (184kW) four-stroke outboard. However, our goal was not just to create an outboard that could deliver 250PS (184kW), but to create an outboard that could deliver high performance that suits its 250PS (184kW) output along with the many benefits that a four-stroke can deliver. A high performance camshaft...

The common idea is that the intake valve opens after the exhaust valve is fully closed however, the intake valve actually starts opening before the exhaust valve fully closes, creating a momentary overlap in the timing where both valves are open. Using VVT (Variable Valve Timing) in the DF250, this overlap can be increased or decreased by altering intake timing with the camshaft, thereby optimizing camshaft timing for low range and mid range operation. As the DF250’s camshaft is already setup to deliver maximum output at high rpm, a change in timing in this range is mostly unnecessary. Increasing...

Multi-Stage Induction longer, curved manifold pipe. The length of the pipe is designed for entering the most suitable volume of fresh air into the chamber to improve combustion and boost lowend torque. As rpm pass a preset threshold, the valve on the direct intake pipe opens up letting air enter directly into the combustion chamber. Short, straight and lacking resistance it gets a greater volume of air into the chamber, increasing the engine’s ability to breathe at high rpm, thus improving high speed power output. The engine cover is designed with a large air intake, which extends from the back...

Two-Stage Gear Reduction the DF250 to turn a 16-inch diameter propeller, which, while being larger than the 14-1/2-inch diameter propeller found on the two-stroke DT225, is also larger than those previously used on a V6 outboards. The propeller used on the DF250 is specially designed for greater acceleration and maximum speed. Along with greater acceleration, the gear reduction in combination with the four-stroke engine’s wide power band is capable of handling a wide variety of loads, which is a significant benefit to boaters whose loads vary from day to day. With such a high performance engine...

s Compact Designs Engine Cover Profile Comparison 55-Degree Bank Angle Creates a Compact V6 With the DF250, one major design objective our engineers set out to realize was to design and produce a compact, narrow profile motor. This was met by abandoning the 60-degree bank angle normally utilized in V-type blocks and designing an all-new V-design block using a 55-degree bank angle—an industry first. When compared to the industry norm of 60-degrees, as shown in the engine cover comparison, the difference in size is quite clear. Brand A V6 Four-Stroke DF250 Cylinder Block Offset Drive Shaft 55°...

Cam Drive System Two-Stage Cam Drive System 20:32=1.60 The two-stage cam drive system utilized in the DF250 incorporates both gears and a chain. The system’s first stage gears transfer power between the crankshaft and the drive shaft (32:40) while the second stage utilizes a chain to deliver power from the drive shaft to the camshaft (20:32). This allows for the use of smaller diameter cam sprockets, which in turn allows for a reduction in valve angles also reducing the size of the cylinder head. The timing chain is equipped with an automatic hydraulic tensioner to keep the chain properly tensioned....

s Excellent Fuel Economy s Low Emissions Multi Point Electronic Fuel Injection Comparison As Suzuki was the first in the industry to incorporate multi point electronic fuel injection in a four-stroke outboard with the DF60 and DF70, it is only natural that the DF250 would incorporate the same. Along with Suzuki’s Multi Point Sequential Fuel Injection, the DF250 incorporates an ECM (Engine Control Module) which constantly monitors crucial data, in real time, from a series of sensors placed in critical areas on the engine. This comprehensive network of sensors includes the Manifold Absolute Pressure...

Tilt Limit Switch efficiently, the ECM relies on a very powerful 32-bit computer which instantly calculates the optimum amount of fuel to be injected at high pressure into each of the cylinders by the Multi Point Sequential Fuel Injection system. This system greatly reduces exhaust emissions allowing the DF250 to pass both the EPA 2006 regulations and CARB 2008 regulations, the strictest exhaust regulations to date, while providing lower fuel consumption, smooth starts, crisp acceleration, smooth performance and maximum efficiency. The motor tilt system incorporates a user settable tilt limit...