TOHATSU 2 Stroke 5BS User guide

OWNER’S WAND E3:,00&

FOREWORD
Thank you for choosing a TOHATSU OUTBOARD MOTOR.
This manual describes its workings and its main features. Before using
the motor study these instructions and get to know what a fine engine
it is. Like any other piece of machinery it requires careful and know-
ledgeable attenlion, and in return it will give you excellent service over
the years. Our policy is one of continuous product improvement so we
reserve the right to incorporate changes without prior notice.
v
TOHATSU CORPORATION

CONTENTS
SPECIFICATIONS .
MAINPARTS . .._...........................
(1) OPERATING INSTRUCTIONS
1. PREPARATIONS BEFORE STARTING THE ENGINE
2. STARTING 81 WARM-UP ~.
3. BREAKING IN A NEW ENGINE
4. HOWTOOPERATE .,..,.,._,.,_......,.,...
5. INSPECTION & ADJUSTMENT
(II) INSPECTION 5 SEAVICING
1. TROUBLESHOOTING ..,........,....,.,....
2. AFTER COMPLETING DAY’S RUNNING
(Ill) OUT-OF-SEASON STORAGE
III/I OPTIONAL EQUIPMENT .
(VI SERVICING TOOLS AND ACCESSORIES
1. TOOLS AND SPARE PARTS
2. AVAILABLE PROPELLER .~..,,..,......,....
(VI) WIRING DIAGRAMS _. _.
1

SPECIFICATIONS
Recommended
operating Range 4.500 - 5,5Wr.!%rn.
Fuel Conr”mDrion
at Marimum Speed 2.5 P/h,
Gear Reducrion
a-*;.. 2.15 12&131
OPTlONAL PARTS
Propeller
Lighting Coil (12” - 4OWI
Rectifier Kit

MAIN PARTS

( I) OPERATING INSTRUCTIONS
1. PREPARATIONS BEFORE STARTING
THE ENGINE
Gasoline with 86 OCTANE (A.K.I.) or over is recom-
mended for easy starting and long life.
(1) Fuel
1) Check that there is sufficient fuel for the day’s
operation. Carry additional fuel for use in an
emergency and check it before running. Running
out of fuel can cause both inconvenience and
serious injury.
2) The fuel should be prepared using genuine TO-
HATSU engine oil. (Fig. 11 The normal mixture is
50 parts gasoline to 1 part oil 150:~). For initial
break in of a new engine the mixture should be
20: 1 for the first ten hours operation.
3) If you are using commercial two stroke (2T) oil
use the ratio 2O:l for normal running and 15:l for
the initial 10 hours running.
4) Do not use poor grade, dirty or stale gasoline or
oil. This will cause poor starting, reduced power
and may damage your motor. Use good quality
fuel and lubricants at all times.
(2) Mounting the outboard motor
11 Position: The center of the stern (Fig. 21
2) Height: Fit the outboard so that the anti-
cavitation ‘plate is lower than the
bottom of the boat by 3 - 5cm
11.2-2in.l. (Fig. 3)
Anti-cavitation plate

3) After mounting the motor on the boat see that
the clamp screws are hand tight.
Check tightness from time to time when under
power. As a safety precaution fasen a safetv rope
from outboard to the boat through the hole of the
clamp bracket so that the engine is not lost in the
event of an accident.
4) Attaching angle
The outboard is positioned by locking the thrust
rod in the appropriate hole of the bracket so that
the drive shaft housing at maximum speed, is
vertical to the surface of the water. (Fig, 5 & 6)
Note: When set or remove the motor on the
boat by hand. hold the lower motor cover
but do not hold the tilt handle of the
upper motor cover.
. The tilt is proper
The boat is level and
the thrust rod is posi-
tioned properly dur-
ing running.
l The tilt is not proper.
The bow rides high
and it is deflected or
hit during running. In
this case the position
of Thrust rod shall be
lowered.
T3
d, l The tilt is not proper.
The bow rides low
during running and
it is washed by the
waves. In this case the
position of thrust rod
shall be upper.
5

2. STARTING &WARM-UP
Note: Do not operate Engine without cooling water.
1. 1) M5B (Integral tank type):
Turn the air vent screw to open on the fuel tank
and open the fuel cock knob (Fig. 7)
2) M50S (Separate tank type):
Plug in the fuel connector A. Open the fuel cock
and the air vent screw on the fuel tank cap and
squeeze the primer bulb about 10 times to fill the
carburetor bowl. (Fig. 81
6
For tanks with a fuel tank auto air-vent. (optional)
There is no need to loosen the air vent screw. An
air vent opens automatically when the connector is
attached to the tank.

2. Place the shift lever in the NEUTRAL position.
The engine cannot be started unless the shift lever
is in the NEUTRAL position. (Fig. 9)
3. Turn the throttle grip on the steering handle to the
START (arrow marked) position.
Pull out the choke knob.
Note: Do not pull out the choke when restart-
ing a warm engine. (Fig. 10)

Gently pull the starter rope until you feel the Confirm that cooling water is discharged from the
ratchet engage. Then give it a sharp tug. cooling water checking port.
When starting the engine. push the choke knob (Fig. 12)
back then return the grip to SLOW position and
run the engine to warm up for sever.4 minutes.
(Fig. 11)
Note: When warming up the engine in a cold
weather, set the choke knob in the half
opened position.
\

The clutch must only be operated when the engine
is operating at idling speeds. To change from
FORWARD to REVERSE, first idle the engine
and shift into NEUTRAL. With the engine still
running slowly engage and gradually increase
REVERSE speed. (Fig. 13)
3. BREAKING IN A NEW ENGINE
“Break-in” is the most important stage in the life
of your new outboard motor. Care in the first 10
hours of running of the engine will be repaid by
better performance, a longer service life and increased
pleasure and more economical operation. During this
period it is extremely important to pay attention to
the iallowing points.
al Warm-up the engine for several minutes at slow
RPM after starting.
bl Do not race the engine but cruise at low to
medium speeds. Never fully open the throttle for
the first 5 hours.
c) Do not accelerate or stop suddenly.
d) Follow oil change and fuel recommendations.
The fuel-mixture for the engine running period is
20 parts gasoline to one part genuine TOHATSU
engine oil. Commercial two stroke oil 15:!.
4. HOW TO OPERATE
(1) Precautions to be taken when beginning
operation
When running increase speed gradually, make sure
that the cooling water is circulating correctly through
the engine. You can check this by noting the flow of
water from the port on the starboard side of the
9

motor. (Fig. 11)
Note: If water is not flowing the engine will
quickly overheat and abnormal wear and
break down of the engine will result. The
Intake Port for the cooling water is situated
on the rear part of the engine under the
Anti-Cavitation Plate. Beware of floating
debris such as rugs, vinyls, etc., so it will not
plug up the ports.
(2) Clutch operation
The clutch must only be operated when the engine is
operating at idling speeds. To change from FOR-
WARD to REVERSE, first idle the engine and shift
into NEUTRAL. With the engine still running slowly
shift into REVERSE and gradually increase speed.
Do not change the shift lever when running at high
speed. This will result in damage to the engine.
Note that if you hit an obstacle while running in
REVERSE with full throttle you can easily damage
the propeller, swivel bracket and stern bracket.
(3) Precautions to be taken when running
1) Always reduce speed before making sharp turns.
2) Adjustment of steering
If the steering feels too tight or too loose, it may
be adjusted by the friction adjust screw. (Fig. 14)
10
31 The throttle grip controls engine speed. Turning it
counterclockwise increases the engine speed.
4) Engine speed
The engine should idle at approx. 850 rpm on
forward and approx. 1000 rpm in NEUTRAL.
And this should be checked by the Tohatsu dealer.
5) The maximum engine speed should be between
4500-5500 rpm at wide open throttle.
In case that the given range of rpm cannot be
maintained. check whether the Propeller is suitable

for your boat or not. If necessary change to the
correct types Your Tohatsu dealer can assist.
6) When the operation of Throttle Grip feels too
tight or too loose, adjust it by turning the adjust
screwL lFi0~ 151
Lighter Heavier
(4) Operation in shallow water
With the shift lever in Neutral or Forward. tilt the
motor up slowly by about 40” and then return the
motor down. the motor will be automatically set at
the shallow rater operation angle. (Fig. 16)
Cautions: In a case of operation in a shallow water,
run at slow trolling speeds when running in
rewrse and do not increase the engine
speed unnecessarily. (Excess speed will
caus.? jump up of the engine which is very
dangerous.)
When running in forward, operate the
engine in a condition that the propeller
7) The position of the handle can be adjusted by
means of the 6mm set screw in the hinge.
11

(5) Stopping (6) Tilt adjustment
Reduce speed to idle and then place shift lever at With the shift lever in Neutral or Forward, tilt the
NEUTRAL. Then press the safety switch until the motor fully up using the tilt handle. The motor will
engine completely stops. (Fig. 17) be automatically tilt-locked. (Fig. 18)

(7) Tilt down
Tilt the motor fully UP and pull the tilt lever up ward
to release the tilt lock. Then lower the motor slowly.
(Fig. 19)
5. INSPECTION & ADJUSTMENT
(1) Fuel swtem
o Check fhe fuel tank to see that it contains
sufficient fuel.
Check that the air vent of the tank cap is clear.
Check the primer bulb and integral tank for cracks
or damage.
Check the fuel filter in the fuel cock nut for dirt.
(Fig. 20)
Check the strainer in the fuel tank. lM5BS)
(Fig. 21)

(2) Spark plug (3) Starter trouble. . for emergency
Replace the spark plug if it is damaged. If the 1) Remove rhe recoil starter.
insulator portion of the plug is covered with dirt it 2) Wind the pull rope around the flywheel.
will short or weak the spark and the engine will not (Fig. 23)
fire.
Keep the plug clean at all times. (Fig. 22)
Too muchfuel:
If the cylinder is flooded with fuel, the plug cannot
ignite as it is wet with fuel. Wipe the plug and dry it.
Remove excessive fuel from the cylinder by turning
the engine with the spark plug removed. After replac-
ing the plug, the engine should start properly.
14

(4) Be sure that cooling water is being
discharged.
If the engine runs continuously without the circula-
tion of cooling water, the engine may seize up due to
overheating.
If cooling water is not being discharged. stop the
engine and check the cooling water system. (Fig. 24)
(5) When increasing vibration abnormally
1) Check the clamp screws for tightness.
2) Check the propeller For deformation by hitting a
obstacle.
3) Check the bolts and nuts for bracket and others
for tightness. (Fig. 25)
15

(11) INSPECTION & SERVICING
1. TROUBLE SHOOTING
The following check list will help you to locate the
source of trouble and to take the necessary repair
action. Remember your local TOHATSU dealer will
always be happy IO give you assistance and informa-
tion.
16

00 0 oooc
0 oooooc
00000000
00000000
0 000000
00000000
3 0000000
The ensine fails to
The engine rotate
at abnormally hig
The engine rotate
at abnormally IOU
The engine runs
ilOWlV.
The engine
Poor acceleration
-!

>
0000 The engine starts
but930”stops.
0 0000
The engine will
not idle.
0 0 0 00 0 0 0 0 0 0 Poor acceleration
0000000 The engine rotate!
at abnormally Kg!
00 00 0000 The engine rotate!
at abnormally low
00000000000 The engine runs
SIOWIV.
0000000 00 The engine
overheats.
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