PRODUCT INFORMATION

DF250T/225T
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 DF70 and DF60 to receive further recogni-
tion from the International Marine Trades Expo-
sition and Convention when they captured the
IMTEC Innovation Award. We were the first to offer
an automotive type 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 DF50 and DF40
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.
DF140 and DF115/90 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 2003
Miami International Boat Show, the DF250T captured the
NMMA (National Marine Manufacturers
Association) 2003 Innovation Award
making this the fourth Innovation
Award for Suzuki.

DF250T

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Innovative Compact High Performance Engine
Delivers the Ultimate in Power and Performance
The engine was designed from the ground up, Delivering 225 HP, the DF225T provides the
specifically for outboard use, by Suzuki engineers who largest displacement in its respective category while
drew on decades of knowledge gained through the its narrow profile makes it, like the DF250T, one of the
manufacture of not only outboards, but also lightest and most compact outboards in their class.
technologically-advanced motorcycles and automobiles.
The product of their labors was an all-new 3.6-liter
DOHC, 24-valve V6 engine that held some of our most
advanced and innovative ideas to date. For the US
market, we created two configurations, each of which
is designed to deliver the ultimate in power and
performance.
The DF250T was the marine industry’s first V6
250 HP four-stroke outboard and Suzuki’s most
powerful outboard built to date. With 3.6 liter displace-
ment and producing 69 HP per liter, it held the greatest
power to displacement ratio and the greatest power
to weight ratio the industry had ever seen in the four-
stroke category.

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THE DF250 — THE ULTIMATE IN PERFORMANCE
DOHC 24-Valve with VVT Delivers High Performance
Torque Curve
Our engineers designed a 3.6-liter V6 engine — the larg-
with VVT
est displacement found in the industry at the time — and
an aggressive cam profile designed specifically for the
DF250T to create the industry’s first V6 250 horsepower
four-stroke outboard.

TORQUE
However, our goal was not just to create an outboard
without VVT
that could deliver 250HP, but to create an outboard that
could deliver high performance that suits its 250HP out-
put along with the many other benefits that a four-stroke
can deliver.
A high performance camshaft designed to deliver 250
horsepower produced the wanted power output, but to
LOW MID HIGH
get the strong mid and low-end torque outboards need ENGINE SPEED
when accelerating requires altering valve timing. In gen- * At the comparison test, Multi-Stage Induction System of the motor was operated.
eral, only using a camshaft setting like those found in
racing engines produces an engine that develops suffi- VVT Actuator
cient low and mid range torque. This is because the valve
timing for intake and exhaust differs according to load Intake
and engine speed.
The common idea is that the intake valve opens after Camshaft
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 Exhaust
both valves are open.

Diagram of VVT Mechanism VVT Actuator

Rotation Direction
Intk Cam Shaft
Cam Shaft Position Sensor

Intk Cam Shaft Ex Cam Shaft

Crank Shaft Retard

Advance

Crank Shaft Position Sensor Oil Oil

Filter Pump
Drain
Crank ECM
Position
Duty Control
Throttle Opening Angle
Throttle Sensor Target
Water Temp Advance
Water Temp Sensor Oil Control Valve (OCV)
Oil Pan
Cam Position
Manifold Pressure Feed
Map Sensor* back
Actual Valve Engine Oil Pressure
Timing
*Manifold Absolute Pressure Sensor Signal
 Using VVT (Variable Valve Timing) in the DF250T, this Multi-Stage Induction (DF250/DF225)
overlap can be increased or decreased by altering intake The DF250 and DF225 utilize multi-stage induction
timing with the camshaft, thereby optimizing camshaft to enhance engine performance by changing the length
timing for low range and mid range operation. As the of intake manifold pipes according to engine speed. The
DF250T’s camshaft is already setup to deliver maximum system utilizes two intake manifold pipes per cylinder,
output at high rpm, a change in timing in this range is one operating at low engine speed and another operat-
mostly unnecessary. Increasing the overlap is necessary ing at high. When the engine is operating at lower rpm,
during acceleration in the low and mid power range, but air enters the combustion chamber through the longer,
no change in timing is required for stable idling. curved manifold pipe. The pipe’s length is designed to al-
In the DF250T’s VVT system there are two chambers low an optimum volume of fresh air into the chamber to
within the VVT actuator, one on the phase angle improve combustion and boost low-end torque.
forward side and another on the phase angle backward As rpm pass a preset threshold, the valve on the direct
side, to which hydraulic pressure is continuously applied intake pipe opens up letting air enter directly into the
to change the valve timing of the intake cam. When the combustion chamber. Short, straight and lacking resist-
engine is stopped, idling or other times that there is no ance it gets a greater volume of air into the chamber, in-
oil pressure in the system, the VVT actuator locks, disen- creasing the engine’s ability to breathe at high rpm, thus
gaging the system. improving high speed power output.
The engine cover is designed with a large air intake,
which extends both sides to provide maximum airflow
Graph Illustrating the Variance in Valve Lift Using VVT into the cowling.

Advance
40 Movable Angle

Ex Valve Intk Valve

Valve Lift

Retard

Crank Angle
Valve Overlap

Air Flow in Multi-Stage Induction Module

Lower rpm High rpm

Close Open
Two-Stage Gear Reduction Along with greater acceleration, the gear reduction in
With such a high performance engine now at our dis- combination with the four-stroke engine’s wide power
posal, losing any power in the propulsion system would band is capable of handling a wide variety of loads, which
be a waste, so our engineers chose an efficient means is a significant benefit to boaters whose loads vary from
of supplying maximum propulsion. A propeller rotating at day to day.
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
■ Compact Designs
larger. So to obtain maximum propulsion, spinning a larg- 55-Degree Bank Angle Creates a Compact V6
er diameter propeller with a suitable pitch is the answer. With the DF250 and DF225, one major design objective
But to spin a larger propeller, more torque in the pro- our engineers set out to realize was to design and
peller shaft becomes necessary. In order to obtain the produce a compact, narrow profile motor. This was met
required amount of torque however, the corresponding by abandoning the 60-degree bank angle normally uti-
increases in weight and resistance due to the use of lized in V-type blocks and designing an all-new V-design
larger gears and a larger gearbox do not always provide block using a 55-degree bank angle—an industry first.
effective results. The answer to this dilemma is found When compared to the industry norm of 60-degrees, as
in the use of a two-stage gear reduction system that shown in the engine cover comparison, the difference in
provides the necessary torque without adding unwanted size becomes quite clear.
bulk and weight.
V6 Cylinder Block
Propeller Diameter Comparison

DT225 DF250T/225T

The DF250 and DF225 utilize a first stage gear reduc-

tion (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 55°
largest gear reduction ratio found in any outboard over
200PS (147kW) two-strokes included. Such a powerful
reduction allows these outboards to turn a 16-inch diam- Engine Cover Profile Comparison
eter propeller, which, while being larger than the 14-1/2-
Brand A V6
inch diameter propeller found on the two-stroke DT225, is Four-Stroke
also larger than those previously used on a V6 outboards.
For this reason, both outboards are equipped with a
propeller specially designed for greater acceleration and
maximum speed.
DF250T/225T

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Offset Driveshaft Two-Stage Cam Drive System
Suzuki’s utilization of an offset driveshaft in the DF140, The two-stage cam drive system utilized in the DF250T
115 and 90 proved to be successful in reducing the size and DF225T incorporate both gears and a chain. The
of the outboard. The DF250T and DF225T benefit from system’s first stage gears transfer power between the
this same design which positions the crankshaft in front crankshaft and the drive shaft (32:40) while the second
of the drive shaft, simultaneously moving the outboard’s stage utilizes a chain to deliver power from the drive
center of gravity forward. This system adds to the com- shaft to the camshaft (20:32). This allows for the use of
pactness of the outboard and provides an improvement smaller diameter cam sprockets, which in turn allows for
in power performance. It also places the engine’s axis of a reduction in valve angles also reducing the size of the
inertia, the point where vibrations produced by the engine cylinder head. The timing chain is equipped with an auto-
are at a minimum, up over the upper engine mount thus matic hydraulic tensioner to keep the chain properly ten-
greatly reducing vibration. sioned. This system provides years of maintenance-free
operation.

Offset Drive Shaft Cam Drive System

20:32=1.60

32:40=1.25

32:40=1.25

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 in-
terfere with VHF radios, fish finders and other marine
electronics. Controlled by the outboard’s powerful 32-bit
computer this system provides each cylinder with opti-
mum spark strength and timing.

12:22=1.83

Plug Top Ignition Coil

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Multi Point Electronic Fuel Injection
As Suzuki was the first in the industry to incorporate into each of the cylinders by the Multi Point Sequential
multi point electronic fuel injection in a four-stroke out- Fuel Injection system. This system greatly reduces ex-
board with the DF70 and DF60, it is only natural that the haust emissions allowing all three outboards to pass both
DF250T and DF225T would incorporate the same. Along the EPA 2006 regulations and CARB 2008 regulations, the
with Suzuki’s Multi Point Sequential Fuel Injection, both strictest exhaust regulations to date, while providing low-
outboards incorporate an ECM (Engine Control Module) er fuel consumption, smooth starts, crisp acceleration,
which constantly monitors crucial data, in real time, from smooth performance and maximum efficiency.
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 Tem-
perature Sensor, Camshaft Position Sensor and Exhaust
Jacket Temperature Sensor. To process all of this data Electronic Control Module
efficiently, the ECM relies on a very powerful 32-bit com- (ECM)
puter which instantly calculates the optimum amount of
fuel to be injected at high pressure

Multi Point Sequential Electronic Fuel Injection (DF250)

Fuel Tank

Low Pressure Fuel Filter

Squeeze Pump

Low Pressure Fuel Pump Vapor Float High

Battery Separator Pressure
Fuel Filter

Purge Control Valve Flywheel

Crankshaft Position Magneto
Sensor (CKP Sensor)

Shift Position Sensor High Pressure

Fuel Pump
Oil Control Valve (OCV)
ECM
Evaporation Hose
Ignition Coil
Fuel Cooler

Neutral Switch
Pressure Regulator Camshaft Position
Sensor (CMP Sensor)
Injector

Intake Manifold

Vacuum Switching
Valve (VSV)
Starter Relay Cylinder Head

Idle Air Control Cylinder Block

Valve (IAC Valve)
Ignition
IG Switch Throttle Body
Main Relay

OFF Silencer
ST

Spark Plug Exhaust Jacket

Temp Sensor

Fuse
Oxygen Sensor (Service tool only)
Intake Air Temp Sensor Pilot Air
(IAT Sensor) Adjust Screw
Cylinder Wall Temp Sensor

Manifold Absolute Pressure Sensor

(MAP Sensor)
Throttle Position Sensor

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■ Durability and Reliability
Keeping The Engine and Components Cool Suzuki Anti-Corrosion Finish
Fitted with fan blades the flywheel serves a dual pur- Suzuki has formulated an anti-corrosion finish that
pose by efficiently expelling heat from within the engine both increases the durability of the engine and protects
cover out of the side of the cowl, keeping the tempera- those parts of the aluminum exterior that are constantly
ture within the cowl under control. exposed to saltwater. The Suzuki Anti-Corrosion Finish is
Water circulating around the oil jacket located at the a specially formulated advanced finish that offers maxi-
base of the V-bank cools oil flowing through the pipe, mum bonding of the finish to the aluminum surface for
keeping oil temperature under control. This contributes to an effective treatment against corrosion.
the cooling of the engine thereby enhancing durability.
Both outboards also utilize piston cooling jets which Acrylic Resin
shoot a stream of oil onto the backside of the pistons to Clear Topcoat

aid in cooling. Fine nozzles deliver a well-defined stream Acrylic Resin

Basecoat
of oil that is precise and accurate. The engines are also
equipped with another cooling jet that shoots a stream of Epoxy Primer
Undercoat
oil onto the main cam chain and drive gear to keep those
Suzuki Anti-Corrosion
components cool and lubricated as well. Finish

Suzuki Aluminum
Alloy

Flywheel Magneto

Piston Cooling Jet

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CARB 3 Stars
The DF250T and DF225T have received the CARB 3-Star
■ Convenient Function
rating, which identifies engines that meet the California Lower cover separates into two sections to allow easier
Air Resources Board’s 2008 exhaust emission standards. access for maintenance to the V6 engine.
The strictest exhaust regulations to date, they represent a
65% reduction in emissions from the EPA 2006 emission An oil change reminder system, built into the Multi-Func-
standards. tion Tachometer (Optional), informs the user with a flash-
ing oil lamp when it is time to change the oil.

Oil changes are easy with the oil drain plug located on
the front of the oil pan, the oil filler cap on the top of the
cylinder head, and a spin-on oil filter.

High Output Alternator A comprehensive monitoring system built into the

The outboards are also equipped with a high output Multi-Function Tachometer (Optional) detects abnormali-
alternator that delivers a total 54 A (12V) of electrical ties in the running of the outboard to provide information
power. Designed to produce a majority of this power at and alerts so that appropriate measures can be taken
low rpm, it generates around 38 A even at a low 1,000 before the problem becomes serious.
rpm—a generous amount of current to keep an assort-
ment of electronics up and running.

Tilt Limit Switch

The motor tilt system incorporates a user settable tilt MODEL SHAFT ROTATION COLOR
limit switch, which prevents
the motor from tilting beyond a DF225TX2 25” STANDARD BLACK
predetermined position. This can Tilt Limit System

be used to protect both the boat DF225TXW2 25” STANDARD WHITE

and motor from damage that can
occur when tilting the motor. DF225TXZW2 25” COUNTER WHITE

DF250TX2 25” STANDARD BLACK

Fuel Filter
The fuel system is equipped with a large and easy to DF250TXW2 25” STANDARD WHITE
maintain fuel filter which removes contaminants from the
fuel before they reach the engine to protect the engine DF250TXZ2 25” COUNTER BLACK
from damage.
DF250TXZW2 25” COUNTER WHITE

DF250TXX2 30” STANDARD BLACK

DF250TXXW2 30” STANDARD WHITE

DF250TXXZ2 30” COUNTER BLACK

DF250TXXZW2 30” COUNTER WHITE

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The DF250T and DF225T are available in
your choice of Pearl Nebular Black or
Cool White

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DF250T/225T SPECIFICATIONS DIMENSIONS
MODEL DF250T/225T
RECOMMENDED FORWARD
X: 25 XX: 30 (250T Only)
TRANSOM HEIGHT IN
STARTING SYSTEM Electric

WEIGHT LBS * X: 606 XX: 626

ENGINE TYPE DOHC 24-Valve

FUEL DELIVERY SYSTEM Multi-Point Sequential EFI
NO. OF CYLINDERS V6 (55-degree) 30 30
286 286
PISTON DISPLACEMENT IN3 220.5 458 458

BORE X STROKE IN 3.75 x 3.35

L:633 X, XX:612 L:1048 X:1148 XX:1263
MAXIMUM OUTPUT HP (PS) DF225T: 225 DF250T: 250 L:139 X, XX:159 L:742 X, XX:722

FULL THROTTLE DF225: 5,000-6,000

OPERATING RANGE RPM DF250: 5,500-6,100

L: 771 X, XX:766
1041
997
STEERING Remote

L: 1715 X:1834 XX:1961

OIL PAN CAPACITY QT 8.5
IGNITION SYSTEM Fully-transistorized

X, XX 53
:405

X:635 XX:762
L:3

L: 508
ALTERNATOR 12V 54A
ENGINE MOUNTING Shear Mount L:78 14
X, XX .5
:81
TRIM METHOD Power Trim and Tilt 9
L:6 :64
XX
X,
GEAR RATIO 2.29:1 6

L: 48
X, XX:47
GEAR SHIFT F-N-R
EXHAUST Through Prop Hub Exhaust Unit: mm

PROPELLER SELECTION (PITCH)** 17”-28”

* Dry weight, including battery cable, not including propeller and engine oil.
**Boats and motors come in a large variety of combinations. See your authorized dealer for correct prop. selection to meet recommended RPM range at W.O.T.
Please read your owners manual carefully. Remember, boating and alcohol or other drugs don’t mix. 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, 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.

DF250T/225T FEATURES
● V-design Engine Block using a ● Tilt Limit Switch
55-degree Bank Angle ● Oil Change Reminder System
● DOHC 24-valve Engine ● Low Oil Pressure Caution
● Variable Valve Timing System (DF250) ● Over-Rev Limiter
● Multi-Stage Induction (DF250/DF225) ● Overheat Cooling Water Caution CARB Three-Star Label EPA 2006 Label
The three-star label identifies Suzuki’s four-stroke
● Multi Point Sequential Electronic Fuel Injection ● Self Diagnostic System engines that meet the technology ensure
● Direct Ignition ● Neutral rpm Limiter California Air Resources compliance with EPA
Board’s 2008 exhaust emission 2006 exhaust emission
● Offset Driveshaft ● Anti-Corrosion Protection standards. Engines meeting standards set by the U.S.
these standards have 65% Environmental Protection
● Two-stage Gear Reduction ● Two Freshwater Flushing Ports lower emissions than EPA 2006 Agency.
● Two-stage Camshaft Drive System ● High Performance 16-in. Diameter exhaust emission standards.
● Flywheel Designed with Fan Blades Stainless Steel Propeller (Optional)
● 54A Alternator ● Multi Function Tachometer (Optional)
● Counter Rotation Models Available

Part No. 99953-22550-019

www.suzukimarine.com Printed in USA