2003 Innovation
Award Winner
Way of Life!
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 oil bathed, self-adjusting timing
chain in a four-stroke engine with performance-enhancing dual overhead cams and four valves
per cylinder. This brought us recognition again, when our DF40 and DF50 received the IMTEC
Innovation Award making Suzuki the first manufacturer to receive this distinguished award two years in a row,
and also giving us our third IMTEC award, again an industry first. DF90/115 and DF140 were the first to offer an
offset driveshaft with a two-stage cam drive system and two-stage gear reduction system, making them the most
compact outboards in their class.
At its first showing at a special preview at the Miami International Boat Show, the DF250 captured the NMMA
(National Marine Manufacturers Association) 2003 Innovation Award making this the fourth of six Innovation Award
for Suzuki.
DF225 Cool White
DF250 Shadow Metallic Black / Cool White
Torque Curve
Compact High Performance Engine
The DF225 and DF250 all utilize a 3.6-liter DOHC, 24-valve V6 engine that produces 225hp / 250hp in their respective
configurations. At 3614cm3 these engines feature big displacement, but innovative design makes them light and the most
compact outboards in their class. Key features shared by these powerful four-strokes include Suzuki’s digital sequential
electronic fuel injection controlled by a 32-bit onboard computer and Suzuki’s offset driveshaft, which allows for the use of a
larger prop. In addition to that, the DF225/250 utilizes multi-stage induction to provide low-end torque. And the DF250 has
variable valve timing for even more low and midrange torque.
TORQUE (50N•m)
with Multi-Stage Induction
without Multi-Stage Induction
DOHC 24-Valve with VVT Delivers High Performance (DF250)
A high performance camshaft designed to deliver 250 hp produced the wanted power output, but to get the
strong mid and low-end torque outboards need when accelerating requires altering valve timing. In general,
only using a camshaft setting like those found in racing engines produces an engine that develops insufficient
low and mid range torque. This is because the valve timing for intake and exhaust differs according to load
and engine speed.
Graph Illustrating the Variance in
Valve Lift Using VVT
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
Torque Curve
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 the overlap is necessary during
acceleration in the low and mid power range, but
no change in timing is required for stable idling.
In the DF250’s VVT system there are two
chambers within the VVT actuator, one on the
phase angle forward side and another on the phase angle backward side, to
which hydraulic pressure is continuously applied to change the valve timing of
the intake cam. When the engine is stopped, idling or other times that there is
no oil pressure in the system, the VVT actuator locks, disengaging the system.
Multi-Stage Induction (DF225/250)
The DF225/250 utilizes multi-stage induction to enhance engine performance by changing the length of intake manifold pipes according to engine speed.
The system utilizes two intake manifold pipes per cylinder, one operating at low engine speed and another operating at high. When the engine is operating at
lower rpm, air enters the combustion chamber through the 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 low-end torque.
Multi-Stage Induction Module
As rpm pass a preset threshold, 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 also designed with a large air intake, which extends to both sides to
provide maximum airflow into the cowling.
Two-Stage Gear Reduction
With such a high performance engine now at our disposal, losing any
power in the propulsion system would be a waste, so our engineers chose an
efficient means of supplying maximum propulsion. A propeller rotating at high
speed in the water has a tendency to slip and when two propellers of the same
pitch but different diameters are rotated, the smaller propeller will slip more
than the larger. So to obtain maximum propulsion, spinning a larger diameter
propeller with a suitable pitch is the answer.
But to spin a larger propeller, more torque in the propeller shaft becomes
necessary. In order to obtain the required amount of torque however, the
corresponding increases in weight and resistance due to the use of larger gears
and a larger gearbox do not always provide effective results. The answer to this
dilemma is found in the use of a two-stage gear reduction system that provides
the necessary torque without adding unwanted bulk and weight.
The DF225/250 utilize a first stage gear reduction (32:40) between the
crankshaft and driveshaft, and a second stage reduction (12:22) in the lower
unit’s gear case, resulting in an overall gear ratio of 2.29. This is the largest
gear reduction ratio found in any outboard over 200HP two-strokes included.
Such a powerful reduction allows these outboards to turn a 16-inch diameter
propeller. (14-1/2-inch diameter propeller found on the competition) For this
reason, a propeller specially designed for greater acceleration and maximum
speed is used on these 4-Stroke V-6 outboards. Along with providing 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.
55-Degree Bank Angle Creates a Compact V6
Cylinder Block
Offset Driveshaft
One major design objective our engineers set out to realize was to
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 becomes quite clear.
Offset Driveshaft
Suzuki’s utilization of an offset driveshaft has proven successful
in reducing the size of the outboard. The DF225/250 benefit from this
same design which positions the crankshaft in front of the drive shaft,
simultaneously moving the outboard’s center of gravity forward. This system
adds to the compactness of the outboard and provides an improvement in
power performance. It also places the engine’s axis of inertia, the point where
vibrations produced by the engine are at a minimum, up over the upper engine
mount thus greatly reducing vibration.
Two-Stage Cam Drive System
The two-stage cam drive system utilized in the DF225/250 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. This system provides years of maintenance-free operation.
Direct Ignition
An advanced direct ignition system used in both of these V6 outboards
utilizes integral type spark plug caps with ignition coils. While reducing the
number of parts and simplifying the wiring system, this arrangement also
greatly reduces electronic engine “noise” that can interfere with VHF radios,
fish finders and other marine electronics. Controlled by the outboard’s powerful
32-bit computer this system provides each cylinder with optimum spark
strength and timing.
Keeping The Engine and Components Cool
Fitted with fan blades the flywheel serves a dual purpose by efficiently
expelling heat from within the engine cover out of the side of the cowl, keeping
the temperature within the cowl under control.
Water circulating around the oil jacket located at the base of the V-bank
cools oil flowing through the pipe, keeping oil temperature under control. This
contributes to the cooling of the engine thereby enhancing durability.
The DF225/250 also utilize piston cooling jets, each of which shoots a stream of
oil onto the underside of the piston to aid in cooling. Fine nozzles deliver a welldefined stream that is precise and accurate. The engines are also equipped
with another cooling jet that shoots a stream of oil onto the main cam chain
and drive gear to keep those components cool as well.
Suzuki Anti-Corrosion Finish
Suzuki has formulated a new anti-corrosion finish that both increases
the durability of the engine and protects those parts of the aluminum exterior
that are constantly exposed to saltwater. The Suzuki Anti-Corrosion Finish is
an specially formulated advanced finish that offers maximum bonding of the
finish to the aluminum surface for an effective treatment against corrosion.
Since 2004, the Suzuki Anti-Corrosion Finish can be found on all four-stroke
models from the DF9.9B and up.
Multi Point Electronic Fuel Injection
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 DF225/250 would
incorporate the same. Along with Suzuki’s Multi Point
Sequential Fuel Injection, the DF225/250 incorporate
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 Sensor, Crankshaft
Position Sensor, Intake Air Temperature Sensor,
Cylinder Wall Temperature Sensor, Camshaft Position
Sensor and Exhaust Jacket Temperature Sensor. To
Injector & Manifold Module
process all of this data efficiently, the ECM relies
on a 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
DF225/250 to comply with both the 2010 EPA* regulations and CARB**
Three Star Ultra Low Emission Standard, the strictest exhaust regulations
to date, while providing lower fuel consumption, smooth starts, crisp
acceleration, smooth performance and maximum efficiency.
CARB 3 Star
The DF225/250 have received the CARB threestar rating which identifies engines that meet the
California Air Resources Board’s Ultra Low exhaust
emission standards. The most stringent exhaust
emission requirements for outboard motors.
Exhaust emission standards set by the U.S.
Environmental Protection Agency.
** Exhaust emission standards set by the
California Air Resources Board.
Multi Point Sequential Electronic Fuel Injection
Fuel Tank
Low Pressure Fuel Filter
Squeeze Pump
Low Pressure Fuel Pump
Fuel Filter
Purge Control Valve
Crankshaft Position
Sensor (CKP Sensor)
Shift Position Sensor
High Pressure
Fuel Pump
Oil Control Valve (OCV)
Evaporation Hose
Fuel Cooler
Ignition Coil
Camshaft Position
Sensor (CMP Sensor)
Pressure Regulator
Neutral Switch
Intake Manifold
Vacuum Switching
Valve (VSV)
Starter Relay
Cylinder Head
Idle Air Control
Valve (IAC Valve)
Throttle Body
Main Relay
Cylinder Block
Spark Plug
Intake Air Temp Sensor
(IAT Sensor)
Exhaust Jacket
Temp Sensor
Oxygen Sensor (Service tool only)
Pilot Air
Adjust Screw
Cylinder Wall Temp Sensor
Manifold Absolute Pressure Sensor
(MAP Sensor)
Throttle Position Sensor
High Output Alternator
Alternator Output
The DF225/250 are equipped with a high output alternator that delivers 54 A(12V) of
electrical power. Designed to produce a majority of this power at low rpm, around 38 A is
delivered even at 1,000rpm. It delivers a generous amount of current to keep an assortment
of electronics up and running.
5000 (rpm)
Tilt Limit Switch
The motor tilt system incorporates a user programmable tilt limit switch, which prevents the motor from
tilting beyond a predetermined position. This can be used to protect both the boat and motor from damage
that can occur when tilting the motor.
Tilt Limit System
New Suzuki Water Detecting System
Water in the fuel can be the source of poor combustion, lower power output, and corrosion. To help protect the engine from
moisture in the fuel, the DF225/250 utilizes a water detecting fuel filter that alerts the operator with both visual and audio
warnings when water is present in the fuel.
Other Features
Counter-rotation models are available for the DF225/250 in 25-inch transom lengths for compatibility with a wider range of offshore boats.
Lower cover separates into two sections to allow easier access for maintenance to the V6 engine.
An oil change reminder system, built into the Multi-Function Tachometer (Optional), informs the user with a flashing oil lamp when it is time
to change the oil.
Oil changes are easy with the oil drain plug located on the port side of the down housing, the oil filler cap on the top of the cylinder head, and
a spin-on oil filter.
A comprehensive monitoring system built into the Multi-Function Tachometer (Optional) detects abnormalities in the running of the outboard
to provide information and alerts so that appropriate measures can be taken before the problem becomes serious.
A tradition of Innovation
Suzuki Motor Corporation
Suzuki history begins with the founding of Suzuki Loom Works by Michio Suzuki in October 1909. Realizing that weaver wanted to produce cloth both vertical and
horizontal patterns, he developed an automated loom capable of weaving patterned cloth from space dyed yarn. His commitment to innovative engineering was the
start of an uncompromising focus on creating products that meet people’s needs and offer new life style possibilities.
While the company has evolved, diversified, and expanded since then, we have always honored our founder’s commitment to innovative engineering. His philosophy
lives on in the “Way of Life!” brand slogan and our dedication to provide our customers with value packed products that bring satisfaction and meet their needs.
Suzuki Motorcycles, ATVs & Scooters
Suzuki’s full lineup of motorcycles, ATVs and scooters lead
the industry with cutting-edge technology, convenient
features, unrivaled performance and superior quality.
With a broad lineup that includes sportbikes, cruisers,
motocross, dual-sport, adventure, scooters, ATVs and more –
Suzuki has built its reputation on performance and innovation.
Suzuki’s motorcycles, ATVs and scooters have
revolutionized the industry and redefined their categories.
The rugged KingQuad ATV line celebrates 30 years as the
“First on 4-Wheels.” The legendary GSX-R line, which
practically invented the modern sportbike when introduced
in 1986, celebrates the unprecedented milestone of over 1
million units produced worldwide. Suzuki’s other product
lines, including Burgman scooters, Boulevard cruisers
and V-Strom adventure motorcycles, continue to innovate
and set the industry-standard for performance, features,
quality and value.
DF300A with Lean Burn. 2011 followed up with additional
design changes for the DF300AP to include the NMMA
Innovation Award Winning (Seventh Time) Select Rotation
drive system. In 2012 Suzuki introduced the NMMA
Innovation Award –Honorable Mention- DF20A/15A with
Battery-less EFI/Lean Burn and the redesigned DF115A/
DF140A with Lean Burn. In the same year, Suzuki also
added the DF250AP with Lean Burn, Select Rotation and
Suzuki Precision Control. These outboards deliver clean
running economical operation with Suzuki’s Lean Burn
Technology. At Suzuki, our goal is to build outboards that
Suzuki Outboards
Ranging from the world’s first 300 hp four-stroke outboard
to the portable DF2.5, Suzuki offers a comprehensive
lineup that represents state-of-the-art design and
technology. These engines offer great fuel efficiency and
environmentally responsible operation that meet many of
the toughest emission standards – worldwide. In 2008
Suzuki introduced the first “New Generation” four-stoke
outboard motors, the DF90A and DF70A, followed by
the DF60A in 2009. 2010 was another big year with the
introduction of the NMMA Innovation Award Winning (Sixth
Time) DF50A/40A with Lean Burn and the redesigned
WEIGHT (lbs.)
BORE X STROKE in. (mm)
n V-design
Four-stroke DOHC 16 valve
X: 25
X: 25 XX: 30
X: 580
X: 580 XX: 591
Multi Point Sequential Electronic Fuel Injection
V6 (55-degree)
220.5 cu. in. (3,614cc)
3.74 x 3.35 (95 x 85)
225 hp / 5500 rpm
250 hp / 5800 rpm
5000–6000 rpm
5500–6100 rpm
On the track, Suzuki has captured major championships
around the world. The experience, knowledge and expertise
gained on the track produces race proven, leading
edge technologies that are utilized in every vehicle we
make. Suzuki supplies you with the best combination of
performance, durability, reliability, efficiency, ease-of-use,
and value. It’s why Champions Choose Suzuki. So, what
are you gonna ride?
8.5 qt. (8.0 ltr)
Solid State Direct Ignition
12V 54A/3000 rpm
Power Trim and Tilt
2.29:1 (Two-Stage Gear Reduction)
Through Prop Hub Exhaust
Suzuki Motorsports
To learn more about Suzuki, visit your local Suzuki dealer or go to
are highly efficient, deliver low fuel consumption and high
power output while placing less stress on the environment.
× 17
x 18 1/2
x 20
x 21 1/2
Cool White
3 x 16 x 23
3 x 16 x 24 1/2
3 x 16 x 26
Shadow Metallic Black / Cool White
Engine Block using a 55-degree
Bank Angle
n DOHC 24-valve Engine
n Variable Valve Timing (DF250)
n Multi-Stage Induction (DF225/250)
n Multi Point Sequential Electronic Fuel
n Direct Ignition
n Offset Driveshaft
n Two-stage Gear Reduction
n Two-stage Camshaft Drive System
n Flywheel Designed with Fan Blades
n 54A Alternator
n Counter Rotation Models Available
n Tilt Limit Switch
n Oil Change Reminder System
n Low Oil Pressure Caution
n Over-Rev Limiter
n Overheat Cooling Water Caution
n Self Diagnostic System
n Neutral rpm Limiter
n Anti-Corrosion Protection
n Freshwater Engine Flush Port
n Large 16-in. Diameter
* The weight of the motors are “Dry-Weight,” not including propeller.
* Boats and motors come in a large variety of combinations. See your authorized dealer for correct
propeller selection to meet recommended RPM range at W.O.T.
Please read your owner’s manual carefully. Remember, boating and alcohol or other drugs don’t
mix. Always use a USCG-approved life jacket. Please operate your outboard safely and responsibly.
Suzuki encourages you to operate your boat safely and with respect for the marine environment.
SUZUKI MOTOR CORPORATION reserves the right to change, without notice or obligation, equipment,
specifications, colors, materials and other items to apply to local conditions. Each model may be
discontinued without notice. Please inquire at your local dealer for details of any such changes.
Actual body colors may differ slightly from the colors in this brochure.
The three-star label identifies
engines that meet the California Air
Resources Board’s most stringent
exhaust emission requirements for
outboard motors.
Suzuki’s four-stroke technology
is compliant with EPA’s stringent
2010 exhaust emission standards
and 2010-later evaporative
emission standards set by the U.S.
Environmental Protection Agency.
P.O. BOX 1100 BREA, CA 92822-1100
DF225/250 Product Information 2016 99953-22550-016
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