TOHATSU TLDI 40 User manual

SERVICE MANUAL
OIL
WASH
OILLEVEL
B

Chapter 1 Specifications
1. Specifications Table ......................................................................1-3
2. Outline Dimensions .......................................................................1-4
3. Background on TLDI......................................................................1-6
1

1-2

1-3
1. Specifications Table
MODEL 40A 50A
Item EPTO EFTO EFO
Overall length (approx.) 630 mm (24.8 in) 1120 mm (44.1 in)
Overall width (approx.) 345 mm (13.6 in) 384 mm (15.1 in)
Transom (S) 1227 mm (48.3 in)
Overall height Transom (L) 1354 mm (53.3 in)
(approx.) Transom (UL) 1481 mm (58.3 in)
Transom (S) 95.5 kg (211 lb) 98.5 kg (217 lb) 88.5 kg (195 lb)
Weight Transom (L) 96.5 kg (213 lb) 99.5 kg (219 lb) 89.5 kg (197 lb)
(approx.) Transom (UL) 99.0 kg (218 lb) 102.0 kg (225 lb) 92.0 kg (203 lb)
Transom (S) 403 mm (15.9 in)
Transom length Transom (L) 530 mm (20.9 in)
(outboard) Transom (UL) 657 mm (25.9 in)
Engine type 3-cylinder inline
Piston displacement 697ml (42.5 cu.in)
Bore & stroke 68 mm (2.68 in) x 64 mm (2.52 in)
No. of cylinders 3
Maximum output 29.4 kW 36.8 kW
Full-throttle range 5150~5850 rpm
Trolling 700 rpm
Idling 700 rpm
Full-throttle fuel consumption (approx.) 17 L/Hr (4.5 US gal/Hr)
Starting system Electric starter motor
Intake system Reed valve
Scavenging system 5-port loop
Exhaust system Through hub
Lubrication system Auto-mixing
Cooling system Forced water-cooling
Water temp. control Thermostat
Ignition system L-CDI
Ignition timing control Electronically advanced
Firing order 1-2-3
Sparkplug Champion RC10ECC
Alternator 12V 280W
Battery 12V 100AH
12V 120AH (0°C or low)
Trim angle 8°~24° 4°~24°
Trim angle settings 5 6
Maximum tilt-up angle 75°
Transom board thickness 31~70 mm (1.22 ~ 2.76 in)
Maximum steering angle 70° 80°
Gear shift Dog clutch (F-N-R)
Gear ratio 1.85 : 1 (13 : 24)
Throttle control Remote-control Tiller handle
Fuel tank 25L (6.60 US gal)
Oil tank 2L (2.1 US qt)
Fuel Unleaded regular gasoline
Engine oil Genuine engine oil or TC-W, 2-stroke marine outboard oil*
Gear oil Genuine gear oil (500 ml) or API GL5, SAE #80
*: Only those products that have been approved.

1-4
2. Outline Dimensions
M 1
M 2
P
NOS
G
HI
Q
D
F
C
B
J
Y
R
U
L
K
T
A
E
S

1-5
External Dimensions
Item Remarks
A 499 mm (19.6 in)
Transom (S) 728 mm (28.7 in)
B Transom (L) 855 mm (33.7 in)
Transom (UL) 982 mm (38.7 in)
Transom (S) 403 mm (15.9 in)
C Transom (L) 530 mm (20.9 in)
Transom (UL) 657 mm (25.9 in)
D 568 mm (22.4 in) Models EFTO, EFO
E 680 mm (26.8 in)
F 85 mm (3.3 in)
G 623 mm (24.5 in) Models EFTO, EFO
H 520 mm (20.5 in)
I 440 mm (17.3 in)
J 30-75 mm (1.2~3.0 in)
K 490 mm (19.3 in)
Transom (S) 800 mm (31.5 in)
L Transom (L) 910 mm (35.8 in)
Transom (UL) 1025 mm (40.4 in)
M1 384 mm (15.1 in) Models EFTO, EFO
M2 345 mm (13.6 in) Model EPTO
N 310 mm (12.2 in)
O 235 mm (9.3 in)
P 565 mm (22.2 in) Models EFTO, EFO
Q 120deg. Models EFTO, EFO
R 12deg.
S 35deg.
T 75deg.
U 161 mm (6.3 in)
Y 54 mm (2.1 in)

3. Background on TLDI
The abbreviation TLDI stands for Two-stroke Low-pressure Direct Injection and
is the name Tohatsu applies to direct fuel-injection system engines.
1. Two-Stroke Low-Pressure Direct Injection (TLDI)
TLDI is the name Tohatsu uses for two-stroke engines that utilize the air-assisted, low-pressure direct
injection system.
The air-assisted, low-pressure direct injection system has been combined with the L-CDI or (Long-arc
duration CDI ignition system and Engine Control Unit (ECU), which performs precision control of fuel
mixture, injection timing and ignition timing to maximize combustion efficiency in the TLDI-50 engine.
The result is better fuel economy, smaller size and greater power in a two-stroke engine.
2. Air-Assisted Low-Pressure Direct Injection
With TLDI, the air-assisted, low-pressure direct injection process involves using an air compressor to
pressurize the fuel supplied by the fuel pump to in order to propel or inject it directly into combustion
chambers in the form of a finely atomized mixture to achieve maximum combustion efficiency.
CARBURETOR TLDI
Compressed air
Pressurized fuel
ExhaustExhaust
Oil
Air
AirAir
Gasoline + Oil
Atomized fuel mixture
r
q
e
w
1-6
q Fuel injector
w Air injector
eSpark plug
rCarburetor

1-7
3. ECU Control
With TLDI, a network of connected sensors enables the Engine Control Unit (ECU) to precisely
regulates fuel mixture injection rate and ignition timing. The ECU also uses a stratified fuel feed process
to provide lean combustion in the low-speed range, while utilizing more homogenized change to ensure
the fuel mixture is distributed uniformly throughout the combustion chamber when operating in the high-
speed range to ensure maximum combustion efficiency.
L-CDI charge coil
Crank-position sensor
(CPS)
Throttle-position sensor
(TPS)
Water-temperature sensor
(WTS)
Oil level sensor
Battery
Key switch
Stop switch
#1, #2 & #3
Fuel injectors
#1, #2 & #3
Air injectors
#1, #2 & #3
Ignition coils
Tachometer
Warning indicators
Warning horn
Fuel-feed pump
(FFP)
Engine Control Unit
(ECU)
➞
➞
➞
➞
➞
➞
➞
➞
➞
➞
➞
➞
➞
➞
➞

Long-duration CDI (L-CDI)
The L-CDI or Long-arc duration CDI ignition system is used as the TLDI ignition system to maximize
combustion efficiency, fuel economy and minimize exhaust emissions. The L-CDI system offers a longer
plug sparking interval, via spark plug, than used with conventional two-stroke engines. This is designed to
ensure more complete combustion of the mixture in the chamber. L-CDI minimizes mis-firing and reduces
fluctuation in engine speed during idling to offer a much smoother engine feel when compared with
conventional two-stroke engines.
Throttle-Position Sensor (TPS)
The throttle-position sensor system is comprised of TPS1 and TPS2. These are used in combination to
detect throttle butterfly valve, position advancer arm position, and to relay the information to the ECU.
Crank-Position Sensor (CPS)
The crank-position sensor is designed to sense the encoder located above the ring gear on the flywheel in
order to detect crankshaft position and transmit the information to the ECU.
Water-Temperature Sensor (WTS)
Positioned on the water jacket installed on the cylinder, the water-temperature sensor (WTS) is used detect
temperature of the cooling water in the cylinder and relay the information to the ECU.
Oil Level Sensor
The oil level sensor is used to detect the level of remaining oil and relay the information to the ECU.
The oil level sensor operates by lighting the indicator on the tachometer and sounding the beeper when
engine oil is low.
Air Injectors
The air injectors are used to inject a fine mist of fuel and air into the combustion chamber for each piston.
The ECU determines the mixture and timing for injecting fuel according to current engine operating
conditions based on information relayed from the various sensors.
Fuel Injector
The fuel injectors supply the fuel in the air rail to the air injectors via the set pieces. The ECU determines the
mixture for injecting fuel according to current engine operation based on information relayed from the
various sensors.
1-8

1-9
4. Fuel Supply System
!0
IN
OUT
Starting the engine activates the fuel pump e, which draws
gasoline from the fuel tank qand routes it through the fuel filter wto the vapor separator r. The gasoline is pressurized in the
fuel-feed pump FFP t; then passes through the high-pressure filter yto the air rail u, from there it is injected into the
combustion chambers. The fuel regulator iregulates components tthrough uin order to maintain gasoline at a differential pressure of 80 kPa (11.4 psi). Any excess gasoline is depressurized and diverted through the FFP case oand back to the vapor separator r. The returned gasoline contains air bubbles left over from being pressurized at t. These bleed from
the top of the vapor separator rto the throttle body !0 and is fed to the air intake system.
q
ot
r
u
i
w
e
y

1-10
5. Air Supply System
e
r
q
t
w
Starting the engine operates the air compressor w, draws air in through the air filter qand
sends compressed air through to the air rail e. From there, the air is drawn in through the air filter qand used as the air intake when injecting the pressurized gasoline into the combustion chamber pressurized by the air compressor w.
The air regulator rregulates components w and ein order to maintain air at the optimum
combustion pressure of 550 kPa (79.8 psi). Any excess air is depressurized and sent to the exhaust tand discharged from the bottom of
the cylinder.
Exhaust
Intake

1-11
6. Oil Supply System
Starting the engine operates the oil pump q, which draws oil from
the oil tank wand routes it through the oil filter eto the oil pump q.
The oil pump channels the oil through four ports to #1 air box r, #2
air box t, #3 air box yand the air compressor u. Ports r, tand
yserve to lubricate the engine’s pistons, while port (7) lubricates
the air compressor.
TLDI includes a recirculation system in which the excess oil from the
air compressor uis diverted to #3 crankcase ifor use in
lubricating the drive gear q. Any oil left over from there is diverted to
#1 crankcase oand the crankcase !0 where it is added to oil from
rand tand reused to lubricate the engine.
q
w
e
r
t y
u
i
o
!0
Check valve
Check valve

1-12

Chapter 2 Servicing Information
1. General Precautions for Servicing...............................................2-3
2. Specifications and Standards Used in Servicing .......................2-4
3.
Lists of Points for Applying Sealant, Adhesive and Lubrication .........2-10
4. Torque Table.................................................................................2-16
5. Special Tools................................................................................2-17
2

2-2

2-3
1. General Precautions for Servicing
Users of this manual should observe the following general precautions when
conducting disassembly and assembly work.
(1) Make sure that the outboard motor is securely mounted on a work stand before starting work.
(2) Take care not to scratch or damage painted surfaces and the mating surfaces where cylinders, the
cylinder head, the crankcase and other parts are joined.
(3) Always replace packing, gaskets, O-rings and split pins with new ones when reassembling engine parts.
Make a point of replacing snap rings as well.
(4) When replacing, be sure to use genuine Tohatsu brand parts and lubricants or products recommended
by Tohatsu.
(5) Always use the recommended special tools to ensure work is done properly.
(6) When disassembling and assembling components, make note of position marks, adding your own
marks if none are provided, as a way to ensure the various parts and components are properly mated
when being reassembled.
(7) To prevent smaller parts, such as bolts, nuts and washers from getting lost or damaged, where possible,
lightly insert or tighten them back in their original locations.
(8) As normal practice, check disassembled parts for any wear or damage by first wiping them clean; then
washing them in solvent.
(9) With reassembly operations it is essential to observe precise detail in centering, vacuum sealing,
lubricating (with oil or grease), packing parts and components, and connecting wiring and piping. Also
ensure there are no blockages in fluid lines.
1) When reassembling parts requiring numerous nuts and bolts (cylinder, crankcase etc.), begin by
alternately tightening diagonally opposed inner bolts, moving in a concentric circle; then tightening
the outer bolts. This will ensure that engine parts are assembled evenly and securely. (Use the
same procedure in the reverse order when disassembling.)
2) When installing oil seals, be careful not to scratch or reverse the sides that mate with the shaft and
always apply grease to the lip surfaces.
3) Confirm the correct quantity and thickness when applying sealant. Applying excessively will result in
the excess portion being excreted into or outside of the case, potentially causing damage. Adhere
strictly to the written instructions when applying adhesives.
4) Apply penetrating oil spray to nuts or bolts that are difficult to remove due to rust and wait 5 minutes
before removing.
5) For the various inspection specifications, torque values, special tools, and the points where sealant,
adhesive and grease are to be applied, refer to the relevant tables.
6) The various nuts, bolts and washers referred to in this manual are listed below.
Name Type Diameter Length
H820 Hexagon bolt 8 mm 20 mm
N8 Hexagon Nut 8 mm
L8 Hexagon Nut 8 mm
W8 Plain washer 8 mm
SW8 Spring washer 8 mm
Screw 620 Pan head screw 6 mm 20 mm
( 10 )Observe all necessary safety procedures to prevent accidents and injury during work operations.

2. Specifications and Standards Used in Servicing
Name of Part Item to check Standard values
•67.96 mm (2.676 in)
Piston
•Top: 0.22 to 0.37 mm
(0.009 to 0.0145 in)
Piston ring •
Second and third: 0.33 to 0.48 mm
(0.013 to 0.019 in)
•0.05 mm (0.002 in)
Crankshaft
Connecting rod • Deflection
• Mating surface •0.03 mm (0.0012 in) or less for
scratches
Cylinder head •0.03 mm (0.0012 in) or less for
distortion
• Mating surface •0.03 mm (0.0012 in) or less for
scratches
•0.03 mm (0.0012 in) or less for
Cylinder distortion
• Cylinder liner scratches and wear
•0.83 MPa (8.5 kg/cm2, 120 psi)
Engine block
Reed valve stopper • Lift height •9.3 to 9.5 mm (0.366 to 0.374 in)
• Fails to close, is worn or damaged
Reed valve
•1.1Ω±15% (Ambient temperature)
Ignition coil
• 12.5 kΩ±15% (Ambient temperature)
ECU • Low-speed ESG trigger •Approx. 3,000 rpm
• High-speed ESG trigger •Approx. 6,000 rpm
2-4
• Ring end gap
Note: If a ring gauge is unavailable,
measure the lower end of the
cylinder bore.
• Deflection
Measure with both ends supported on V
blocks.
• Compression
Measure after warming:
Remove all 3 spark plugs.
Remove air injector and fuel injector
connectors.
• Primary coil resistance (between black
& white and orange lines)
• Secondary coil resistance (between
high tension core and B line)
• Outer diameter
Measure at a point 12 mm (0.47 in)
above the lower edge of the piston skirt.

2-5
Service limit Servicing procedure
• 0.8 mm (0.031 in) or more
• 0.9 mm (0.035 in) or more
• 0.05 mm (0.002 in) or more • Replace with new crankshaft.
• 2 mm (0.08 in) or more • Replace with new crankshaft assembly.
• Repair by polishing the surface plate, starting
with #240 to #400 grit sandpaper and finishing
with #600 grit sandpaper.
• Repair by polishing the surface plate, starting
with #240 to #400 grit sandpaper and finishing
with #600 grit sandpaper.
• Bore and hone to ø68.55 (2.699 in) + 0 to 0.02
mm (0 to 0.0008 in). Check ports and grind if
necessary.
Use oversize pistons and piston rings.
1) When difference in compression between
cylinders exceeds 0.1 MPa
(1.05 kg/cm2, 14.5 psi)
2) When abnormally higher than standard value 2) Remove carbon from piston crown and cylinder
head surfaces and clean exhaust gas bypass
valve.
• No longer conforms to standard value • Replace with new part.
• Valve reed fails to close
• Excessive wear on valve seat • Replace entire valve assembly.
• Valve is damaged
1) Bore and hone to ø68.55 (2.699 in) + 0 to 0.02
mm (0 to 0.0008 in). Check ports and grind if
necessary.
Use oversize pistons and piston rings.
• When the cylinder liner cannot be repaired using
#400 to #600 sandpaper due to excessive
scratching or scoring or when the difference
between the maximum and minimum points of
wear in liner bore is 0.06 mm (0.0024 in) or more
• Replace with new piston ring if cylinder liner
wear has not yet exceeded the repair limit.
• Scratch depth or distortion is 0.03 mm
(0.0012 in) or more
• Scratch depth or distortion is 0.03 mm
(0.0012 in) or more

Name of Part Item to check Standard values
Magneto
Spark plug
Crank-position
sensor (CPS)
Thermostat
Fuse
Pump impeller
Pump case liner
Guide plate
Propeller shaft
Drive shaft
Starter motor
Anode
Oil seals
2-6
• Sparking performance
Measured using spark tester
• Sparking order
• Alternator (max.)
• Charging performance
• Exciter coil resistance value (low-speed)
(W/R wire to W/L wire)
• Exciter coil resistance value (high-speed)
(Green wire to W/Y wire)
• Lighting coil resistance value
(Y to Y wire)
• Standard plug
• Plug gap
• Gap with encoder ring (flywheel)
• Pickup coil resistance value
(L wire to G wire)
• Opening and closing of thermostat valve
• Capacity
• Wear and cracks
• Damage to bearing
• Wear on lip of oil seal
• Damage to bearing
• Shaft run-out
• Wear on lip of oil seal
• Battery
• Output
• Brush length (wear limit)
• Commutator under-cut (wear limit)
• Commutator diameter (wear limit)
• Corrosion
•10 mm (0.39 in) or more at
350 rpm
•#1 ⇒#2 ⇒#3
•280 W
•1,500 rpm12V 16.5A
•5,500 rpm12V 18.5A
•515Ω±15%
(Ambient temperature)
•71.8Ω±15%
(Ambient temperature)
• 0.38Ω±15%
(Ambient temperature)
•CHAMPION: RC10ECC
•1.0 to 1.1 mm (0.039 to 0.043 in)
•0.5 to 0.9 mm (0.019 to 0.035 in)
•0.531Ω±15%
(Ambient temperature)
•Valve start temperature:
52°C (125.6°F)
•Valve full-open temperature:
65°C (149.0°F)
•Valve full-open lift:
3 mm (0.12 in) or more
•15A ×2, 30A ×1
•0.3 mm (0.012 in) or less (Using
both center holes for reference)
•12V, 100AH-120AH
•12V to 0.6 kW
•12.5 mm (9.5 mm)
0.49 in (0.37 in)
•0.5 to 0.8 mm (0.2 mm)
0.02 to 0.03 in (0.01 in)
•30 mm (29 mm)
1.18 in (1.14 in)

2-7
Service limit Servicing procedure
1) 1.2 mm (0.047 in) or more 1) Repair so that plugs conform to standard values.
2) When electrodes show excessive wear 2) Replace with new spark plug.
• When sensor no longer conforms to standard • Repair so that sensor conforms to standard value.
value
• When fuse burns out • Replace with new fuse.
• When the tips, and upper and lower surface
lip areas show wear, cracks or damage • Replace with new assembly.
• When depth of wear is 0.1 mm (0.004 in) or more • Replace with new shaft.
• Replace with new shaft.
• 0.4 mm (0.016 in) or more • Repair so that shaft conforms to standard values.
• When depth of wear is 0.1 mm (0.004 in) or more • Replace with new shaft.
• Replace with new starter motor.
• When anode shows excessive corrosion • Replace with new anode.
• When lip area shows deterioration, heat
discoloration or damage or when wear • Replace with new oil seal.
reduces interference to 0.5 mm (0.02 in) or less