Suzuki DF20A Specifications
| Engine Model: Suzuki DF20A |
| Engine Type: 4-stroke 2-cylinder OHC gasoline outboard engine |
| Total Displacement: 20.1 cu.in (327 cc) |
| Rated Engine Power: 20 Hp (14.7 kW) at 6300 rpm |
| Fuel System: Multi-point sequential electronic fuel injection |
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The Suzuki DF20A is a technologically advanced
portable outboard that sets new standards in its class. Its
groundbreaking Battery-Less Electronic Fuel Injection system operates
without the need for a battery, an industry first in this Hp class,
ensuring reliable starting and smooth running performance while shedding
unnecessary weight.
The addition of Suzuki's proven Lean Burn Control technology monitors
engine performance and operating conditions to deliver the optimal
air-fuel mixture, resulting in significant fuel savings and reduced
emissions throughout the operating range.
The engine features an Easy Start recoil system with exceptionally light
pull effort, making starts exceptionally easy for everyone. Built with
Suzuki's advanced anti-corrosion system for durability in marine
environments, the DF20A offers user-friendly operation combined with
state-of-the-art engineering. At just 44 kg, it is the lightest outboard
in its class, making it an ideal power source for small fishing boats,
inflatables, and as a dependable auxiliary engine.
Engine Model - Suzuki DF20A, DF20AE, DF20AR, DF20AT, DF20ATH
Engine Type - 4-stroke two-cylinder OHC gasoline outboard engine
Number of Cylinders - 2
Displacement - 327 cc (20.1 cu-in)
Cylinder Bore - 60.4 mm (2.38 in)
Piston Stroke - 57.0 mm (2.24 in)
Maximum Engine Power - 14.7 kW (20.0 hp)
Full Throttle Operating Range - 5300 - 6300 r/min
Idle Speed - 800 - 900 r/min
Fuel System Type - Multi-Point Sequential Electronic Fuel Injection with
Lean Burn Control
Fuel Pump Type - Integral with battery-less operation
Fuel Type - Unleaded gasoline (91 octane minimum)
Ignition System - Digital CDI
Cooling System - Water-cooled with thermostat and Fresh Water Flushing
System
Exhaust System - Through propeller hub
Starting System - Manual recoil or electric
Choke System - Automatic via EFI system
Gear Shift - Forward - Neutral - Reverse
Gear Ratio - 2.08:1
Steering System - Tiller Handle or Remote Control
Trim and Tilt System - Manual Trim and Tilt (5 tilt pin positions) or
Power Tilt
Transom Height (Short Shaft) - 381 mm (15 in)
Transom Height (Long Shaft) - 508 mm (20 in)
Dry Weight (Short Shaft, Manual) - 44.0 kg (97.0 lbs)
Dry Weight (Short Shaft, Electric) - 48.0 kg (105.7 lbs)
Dry Weight (Long Shaft, Manual) - 45.0 kg (99.0 lbs)
Dry Weight (Long Shaft, Electric) - 49.0 kg (108.0 lbs)
Alternator Rating - 12V 6A (manual start) or 12V 12A (electric start)
The powerhead is constructed around an inline two-cylinder configuration
with a displacement of 327 cc. The engine is a 4-stroke cycle gasoline
unit featuring SOHC valve mechanism with two valves per cylinder. The
cylinder bore inside diameter measures 60.400-60.415 mm, with a maximum
permissible out-of-round of 0.050 mm. The piston skirt diameter is
60.365-60.380 mm, resulting in a piston-to-cylinder clearance of
0.0271-0.0425 mm.
The piston pin outside diameter is 15.995-16.000 mm, with a piston pin
bore inside diameter of 16.002-16.008 mm, providing a clearance of
0.002-0.013 mm. The connecting rod big end inside diameter is
29.025-29.034 mm, with a crank pin outside diameter of 28.989-29.000 mm,
resulting in an oil clearance of 0.025-0.045 mm. Connecting rod side
clearance at the big end is 0.100-0.250 mm. The crankshaft journal
outside diameter is 31.989-32.000 mm with an oil clearance of
0.020-0.047 mm.
Maximum crankshaft runout is 0.040 mm and crankshaft thrust play is 0.6
mm. The piston rings include a top ring, second ring, and oil ring. The
top ring has a width of 1.02-1.04 mm and an end gap of 0.12-0.25 mm. The
second ring width is 1.21-1.23 mm with an end gap of 0.26-0.39 mm. Top
ring side clearance is 0.030-0.070 mm, while second ring side clearance
is 0.02-0.06 mm.
The cylinder head incorporates the SOHC valve train with two valves per
cylinder. The SOHC is mounted over the cylinder head and driven by the
crankshaft through a timing belt. Unlike conventional overhead valve
(OHV) engines, this design has no push rods, allowing more direct valve
movement that follows crankshaft rotation without delay. The cylinder
head warp limit is 0.050 mm. Minimum valve head thickness for both
intake and exhaust valves is 0.50 mm.
The intake valve stem outside diameter is 5.475-5.490 mm, while the
exhaust valve stem is 5.450-5.465 mm. Valve guide inside diameter for
both valves is 5.500-5.512 mm. Intake valve stem-to-guide clearance is
0.010-0.037 mm, and exhaust clearance is 0.035-0.062 mm. Valve seat
width for both intake and exhaust is 0.9-1.1 mm. The valve spring free
length is 33.16 mm. Intake cam height is 23.710-23.870 mm, while exhaust
cam height is 23.530-23.690 mm.
Camshaft journal outside diameter is 24.959-24.980 mm for the upper
journal and 22.959-22.980 mm for the lower, with an oil clearance of
0.020-0.062 mm. Valve lash is set to 0.16-0.20 mm for both intake and
exhaust valves.
The DF20A features a revolutionary Multi-Point Sequential Electronic
Fuel Injection system that operates without a battery, an industry first
in this Hp class. All-new components including an inline high-pressure
fuel pump, fuel cooler, vapor separator, fuel injectors, and a new
throttle body were designed to be as compact and lightweight as
possible. The system provides quicker starts, smoother running
performance, and superior acceleration in all operating conditions.
Suzuki's Lean Burn Control technology predicts fuel requirements based
on operating conditions and delivers the optimal air-fuel mixture to the
engine, resulting in remarkable fuel economy throughout the operating
range. A standard 12-liter external fuel tank is included with the
engine. The engine is designed to run on unleaded gasoline with a
minimum octane rating of 91.
The lubrication system is a pressure-fed wet sump design utilizing a
trochoid-type cam-driven oil pump to ensure reliable oil delivery to all
critical engine components. This pressurised system reduces friction and
wear, enhancing engine longevity.
The engine includes a replaceable cartridge-style oil filter. Engine oil
capacity is 1.00 liter of SAE 10W-30 or 10W-40 oil, meeting API service
classifications SG through SN. A low oil pressure warning system
protects the engine from operation with insufficient oil pressure.
Engine temperature is regulated by a water-cooled system with a
thermostat. Cooling water is drawn into the engine through intakes on
the gearcase and circulated by a rubber impeller water pump. A
thermostat maintains optimal operating temperature for combustion
efficiency and performance.
The Fresh Water Flushing System allows owners to easily flush cooling
passages with fresh water after use in salt or polluted water. A
cylinder temperature sensor prevents engine overheating. A tell-tale
port provides visible confirmation that the cooling system is
operational.
| Mid Section and Lower Unit |
The mid-section houses the driveshaft and provides the mounting
interface to the transom bracket. The engine mounting utilizes a shear
mount design to isolate and dampen vibration from the hull. The lower
unit contains the gearcase, which is filled with 0.25 liters of Suzuki
Outboard Motor Gear Oil or GL5 SAE 90 gear oil.
The gears provide a reduction ratio of 2.08:1, optimizing propeller
speed for effective thrust. The shift mechanism enables smooth and
positive engagement of Forward, Neutral, and Reverse gears. Exhaust
gases are expelled through the propeller hub for quieter operation.
Trim and tilt adjustments are available in both manual and power
configurations depending on model selection. Manual trim systems use a
pin in one of five tilt pin positions on the transom bracket. Power tilt
models provide smooth tilting of the outboard with greater convenience
and improved easier operation.
A tilt release lever on manual models disengages the lock for tilting
the engine out of the water for beaching, trailering, or storage.
Shallow water drive settings provide additional versatility for
operation in minimal water depths.
The DF20A is designed to use three-bladed aluminum propellers. The
standard propeller diameter is 235 mm (9.25 in). The standard propeller
supplied is a 3 x 9.25 x 10 pitch model.
A wide range of propeller pitches is available from 7 inches to 12
inches to accommodate different boat and loading conditions. Selecting
the correct pitch is crucial for allowing the engine to operate within
its recommended full-throttle RPM range of 5300-6300 for optimal
performance and efficiency.
The short shaft model, designed for a 381 mm (15 in) transom, has a dry
weight of 44.0 kg (97.0 lbs) for manual start tiller models. The short
shaft electric start model weighs 48.0 kg (105.7 lbs). The long shaft
manual start model, for a 508 mm (20 in) transom, weighs 45.0 kg (99.0
lbs), while the electric start version weighs 49.0 kg (108.0 lbs).
Models equipped with power trim and tilt have a weight of approximately
52.5-54.0 kg depending on shaft length.
Every 100 hours of operation or annually, the following tasks should be
performed: change engine oil, change gear oil, check spark plugs
(adjusting gap to 0.8-0.9 mm), inspect breather and fuel line, check low
pressure fuel filter, inspect sacrificial anodes, verify thermostat
operation, check propeller nut and cotter pin, and check battery
condition on electric start models.
Every 200 hours, in addition to the 100-hour checks, the engine requires
replacement of the oil filter, inspection and adjustment of valve lash,
inspection of the timing belt, checking and adjusting idle speed, and
inspecting the water pump and its impeller.
Every 300 hours, the spark plugs should be replaced with NGK MR6K-9, and
the water pump impeller must be replaced to prevent cooling system
failure. Every 400 hours, the timing belt should be replaced and the
fuel filter should be replaced. Engine oil capacity is 1.00 liter.
Gearcase capacity is 0.25 liters. Spark plug gap is 0.8-0.9 mm. Valve
lash is 0.16-0.20 mm for both intake and exhaust valves. Ignition timing
is 5-20 degrees BTDC.
Cylinder head bolt - 15 Nm first step, 30 Nm final step (11 lb-ft first,
21.7 lb-ft final)
Cylinder head cover bolt - 10 Nm (7.2 lb-ft)
Conrod cap bolt - 10 Nm (7.2 lb-ft)
Flywheel nut - 90 Nm (65.0 lb-ft)
Camshaft pulley bolt - 10 Nm (7.2 lb-ft)
Timing pulley nut - 50 Nm (36.0 lb-ft)
Side cover screw - 5 Nm (3.6 lb-ft)
Spark plug - 10-12 Nm (7.5-9.0 lb-ft)
Tiller handle bolt - 23 Nm (16.5 lb-ft)
Tiller handle bracket bolt - 23 Nm (16.5 lb-ft)
Steering friction adjuster nut - 9 Nm (6.5 lb-ft)
Throttle grip screw - 3 Nm (2.1 lb-ft)
Driveshaft housing bolt - 23 Nm (16.5 lb-ft)
Shallow drive arm bolt - 25 Nm (18.0 lb-ft)
Clamp bracket shaft nut - 43 Nm (31.0 lb-ft)
Propeller nut - 18 Nm (13.0 lb-ft)
Gearcase bolt - 17 Nm (12.3 lb-ft)
Water pump case nut - 6 Nm (4.3 lb-ft)
Bearing housing bolt - 8 Nm (5.8 lb-ft)
Power unit mounting bolt - 23 Nm (16.5 lb-ft)
Intake manifold - 23 Nm (16.5 lb-ft)
Throttle body - 11 Nm (8.0 lb-ft)
Low pressure fuel pump bolt - 10 Nm (7.2 lb-ft)
Fuel delivery pipe bolt - 11 Nm (8.0 lb-ft)
Starter motor mounting bolt - 23 Nm (16.5 lb-ft)
Engine oil drain plug - 9.5 lb-ft (13 Nm)
Oil filter cover bolts (6mm) - 6-8.5 lb-ft (8-11.5 Nm)
The Suzuki DF20A is engineered for a wide variety of watercraft
applications. Its compact size, light weight, and advanced features make
it an ideal primary power source for small fishing boats, aluminum
boats, jon boats, skiffs, dinghies, and inflatable craft including RIBs
for coastal waters or lakes. It is particularly well-suited for boats
requiring a portable outboard with advanced EFI technology and
exceptional fuel efficiency.
The engine is also a popular and dependable choice as an auxiliary motor
for larger fishing boats or sailboats, providing reliable power and
maneuverability. With its 20 hp output, advanced EFI technology
featuring Lean Burn fuel efficiency, and lightweight construction, it is
well-suited for recreational boaters and anglers seeking an efficient,
quiet, and reliable outboard for various water conditions.
The engine is saltwater rated and suitable for use in both freshwater
and saltwater environments when properly maintained, featuring Suzuki's
special anti-corrosion treatment to protect against corrosive elements.
The DF20A meets current European emission and noise regulations.
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