O.S. engine max-18tz series Setup guide

It is of vital importance, before attempting to
operate your engine, to read the general
'SAFETY INSTRUCTIONS AND WARNINGS'
section on pages 2-5 of this booklet and to strictly
adhere to the advice contained therein.
● Also, please study the entire contents of this
instruction manual, so as to familiarize yourself
with the controls and other features of the
engine.
Keep these instructions in a safe place so that
you may readily refer to them whenever
necessary.
It is suggested that any instructions supplied
with the vehicle, radio control equipment, etc.,
are accessible for checking at the same time.
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1
CONTENTS
SAFETY INSTRUCTIONS AND
WARNINGS ABOUT YOUR O.S. ENGINE
ENGINE CONSTRUCTION, NOTES WHEN
APPLYING AN ELECTRIC STARTER
18TZ SERIES INSTRUCTIONS
TOOLS, ACCESSORIES, etc.
BASIC ENGINE PARTS, CARBURETOR
CONTROLS (11K), (11L)
GLOWPLUG, INSTALLATION,
NOTES CONCERNING THE RECOIL STARTER
PRESSURIZED FUEL SYSTEM,
STARTING THE ENGINE & RUNNING-IN
('Breaking-in)
2-5
6-7
8
11-13
14-16
17-20
FINAL ADJUSTMENT,
CARBURETOR CLEANLINESS
CARE AND MAINTENANCE,
CHECKING THE ENGINE
TROUBLE SHOOTING
ENGINES EXPLODED VIEW &
PARTS LIST
CARBURETOR EXPLODED VIEW &
PARTS LIST
O.S. GENUINE PARTS & ACCESSORIES
THREE VIEW DRAWING
38-41
9-10
42-44
24-25
26-29
30-37
21-23
45-48

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2
Remember that your engine is not a "toy", but a highly efficient internal-
combustion machine whose power is capable of harming you, or others, if it is
misused.
As owner, you, alone, are responsible for the safe operation of your engine, so act
with discretion and care at all times.
If at some future date, your O.S. engine is acquired by another person, we would
respectfully request that these instructions are also passed on to its new owner.
SAFETY INSTRUCTIONS AND WARNINGS ABOUT YOUR O.S. ENGINE
The advice which follows applies basically to ALL MODEL ENGINES and is
grouped under two headings according to the degree of damage or danger
which might arise through misuse or neglect.
WARNINGS NOTES
These cover events which
might involve serious (in
extreme circumstances, even
fatal) injury.
These cover the many other
possibilities, generally less obvious
sources of danger, but which, under
certain circumstances, may also
cause damage or injury.
3
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WARNINGS
Model engine fuel is poi-
sonous. Do not allow it to
come into contact with the
eyesormouth.Alwaysstore
it in a clearly marked con-
tainer and out of the reach
of children.
Model engine fuel is also
highly flammable. Keep it
away from an open flame,
excessive heat, sources of
sparks, or anything else
which might ignite it. Do not
smoke or allow anyone else
to smoke, near to it.
Never operate your engine in an en-
closed space. Model engines, like
automobile engines, exhaust deadly
carbon-monoxide. Run your engine
only in an open area.
Model engines generate
considerable heat. Do not
touch any part of your
engine until it has cooled.
Contact with the muffler
(silencer), cylinder head
or exhaust header pipe, in
particular, may result in a
serious burn.
••
•
•

4
NOTES
Before starting the engine, always check
the tightness of all the screws and nuts
especially those of joint and movable
parts such as throttle arm. Missing
retightening the loose screws and nuts
often causes the parts breakage that is
capable of harming you.
This engine is intended for model cars.
Do not attempt to use it for any other
purpose.
Mount the engine in your model
securely, following the manufacturers'
recommendations, using appropriate
screws and locknuts.
Fit an effective silencer (muffler).
Frequent close exposure to a noisy
exhaust (especially in the case of the
more powerful highspeed engines) may
eventually impair your hearing and such
noise is also likely to cause annoyance
to others over a wide area.
The wearing of safety glasses is also
strongly recommended.
Take care that the glowplug clip or
battery leads do not come into contact
with rotating parts. Also check that the
linkage to the throttle arm is secure.
For their safety, keep all onlookers
(especially small children) well back (at
least 20 feet or 6 meters) when
preparing your model for running.
5
NOTES
To stop the engine, fully retard the
throttle stick and trim lever on the trans-
mitter, or, in an emergency, cut off the
fuel supply by pinching the fuel delivery
line from the tank.
Warning! Immediately after a glowplug-
ignition engine has been run and is still
warm, conditions sometimes exist
whereby it is just possible for the engine to
abruptly restart if it is rotated over
compression WITHOUT the glowplug
battery being reconnected.
Pull the operating handle straight out
when starting the engine, so that the cord
does not rub against the vehicle body or
engine. This will help prevent the cord
from being damaged by abrasion or
engine heat.
Do not extend the starter cord more than
40cm (16"). Do not abruptly release the
operating handle. Allow the cord to
rewind smoothly while still holding the
handle.
Do not attempt to disassemble the recoil
starter of the 18TZ-TX. If you do so, the
very strong spring inside will be suddenly
ejected. This can be very dangerous.

6
Piston
Cylinder Liner
Crankshaft
ENGINE CONSTRUCTION
With this engine, the piston will
feel tight at the top of its stroke
(TDC) when the engine is cold.
This is normal. The cylinder bore
has a slight taper. The piston
and cylinder are designed to
achieve a perfect running
clearance when they reach
operating temperature.
Near TDC
Slight taper
When the engine is cold. When the engine is hot.
7
NOTES WHEN APPLYING
AN ELECTRIC STARTER
Do not over-prime. This could
cause a hydraulic lock and damage
the engine on application of the
electric starter.
If over-primed, remove glowplug,
close needle-valve and apply
starter to pump out surplus fuel.
Cover the head with a rag to
prevent pumped out fuel getting
into your eyes.
As delivered, the engine has the
carburetor lightly fit into its intake.
Secure it changing its angle
according to the car chassis.
NOTE

8
This manual handles the following four versions.
MAX-18TZ-T with 11L carburetor
MAX-18TZ(S)-T with 11L carburetor
MAX-18TZ-TX with 11L carburetor
MAX-18TZ(P)-T with 11K carburetor
MAX-18TZ SERIES INSTRUCTIONS
Exhaust Seal Ring 1piece
Standard accessories
Glow Plug P3 T-type head (Turbo head)
1piece
(Hot Type)
About Head Gasket
These engines are fit with two head gaskets
0.1mm thick and 0.2mm thick. It is suggested
to adjust the total thickness according to
atmospheric temperature, humidity and
glowplug used.
At early stage of running-in, when a glowplug
tends to burn out early or when high
nitromethane content fuel is used, try to run
the engine as it is or removing the 0.1mm
gasket.
When low nitromethane content fuel is used,
try to run the engine removing the 0.2mm
gasket.
The 18TZ series engines have been
developed for 1/10 class stadium trucks,
off-road vehicles and sport cars. All the
engine are supplied with T type P3 plug.
18TZ-TX is equipped with a newly
developed O.S. No. N1 recoil starter.
About the engine
9
FUEL
Generally, it is suggested that the user selects a fuel
that is commercially available for model two-stroke
engines and contains 10-30% nitromethane. As a
starting point, we recommend a fuel containing 20%
nitromethane, changing to a fuel containing more
nitro if necessary. When the brand of fuel is
changed, or the nitro content increased, it is
advisable to repeat the running-in procedure
referred to in the RUNNING-IN paragraphs. Please
note that with high-nitro fuels,
although power may be increased
for competition purposes,
glowplug elements do not last as
long and engine life will be
shortened.
Items necessary for starting
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REMINDER!
Model engine fuel is poisonous. Do
not allow it to come into contact with
the eyes or mouth. Always store it in a
clearly marked container and out of
the reach of children.
Model engine fuel is also highly
flammable. Keep it away from open
flame, excessive heat, sources of
sparks, or anything else which might
ignite it. Do not smoke or allow anyone
else to smoke, near to it.
FUEL FILTER
To be installed in the fuel line
between fuel tank and carburetor
to prevent dust from entering the
carburetor.
TOOLS, ACCESSORIES, etc.
The following items are necessary for operating the
engine.
GLOWPLUG IGNITER
Commercialy available handy
glowplug heater in which the
glowplug battery and battery
leads are integrated.

10
FUEL PUMP
For filling the fuel tank, a simple,
polyethylene "squeeze" bottle,
with a suitable spout, is required.
STARTER BOX
SILICONE FUEL LINE
Heatproof silicone tubing of
approx. 5mm o.d. and 2mm i.d.
is required for the connection
between the fuel tank and
engine.
7.2V BATTERIES FOR STARTER BOX
Batteries for starter box.
Select according to the
starter box used. Be sure to
full charge before using.
For starting the engine.
It is not necessary for
the recoil starter ver-
sion-i.e. 18TZ-TX.
TOOLS
HEX SCREWDRIVER
SCREWDRIVER
Necessary for engine installation.
1.5mm, 2mm, 2.5mm, 3mm
Necessary for carburetor adjustments.
No.1, No.2, etc
LONG SOCKET WRENCH WITH PLUG GRIP
Recommended for easy removal and
replacement of the angled and recessed
glowplug, the O.S.Long Socket Wrench
incorporates a special grip.
11
MAX-18TZ-TX
MAX-18TZ(P)-T
Heatsink Head
Crankcase
Mounting Lugs
Exhaust
Cover Plate
Carburetor
Type 11K
Crankshaft
BASIC ENGINE PARTS
Carburetor
Type 11L
Crankshaft
Crankcase
Mounting Lugs
Exhaust
Heatsink Head
Starter Handle
Recoil Starter
Assembly No.N1
Drive Hub
Rear Adaptor

12
CARBURETOR CONTROLS (11K)
The Needle-Valve:
The Mixture Control Valve:
Four adjustable controls are provided on
this carburetor.
For adjusting the mixture strength when the
throttle is fully open.
For changing the mixture strength at mid
speed and acceleration. (Do not rotate the
screw more chan one turn.)
The Throttle Stop Screw:
For setting the minimum idle speed:
For adjusting the mixture strength at part-
throttle and idle speed, to obtain steady
idling and smooth acceleration to mid speed.
The Metering Needle:
NOTE: Readjustment may be necessary,
occasionally to allow for changes in fuel
formula, gear ratio or clutch engagement
point.
Metering Needle
Throttle Stop
Screw
Mixture Control Valve
Needle Valve
Thermo Insulator
13
CARBURETOR CONTROLS (11L)
The Needle-Valve:
The Mixture Control Screw:
The Throttle Stop Screw:
For adjusting the mixture strength when the
throttle is fully open.
For adjusting the mixture strength at part-
throttle and idle speed, to obtain steady
idling and smooth acceleration to mid
speed.
For setting the minimum idle speed:
Throttle Stop
Screw Mixture Control Valve
Needle Valve
Thermo Insulator NOTE: Readjustment may be necessary,
occasionally to allow for changes in fuel
formula, gear ratio or clutch engagement
point.
Three adjustable controls are provided on
this carburetor.

14
Since the compatibility of the glowplug and fuel
may have a marked effect on performance and
reliability, it may be worthwhile to choose the
R/C type plug found most suitable after
tests. Recommended O.S. plugs are P3 and P6.
Carefully install plug finger-tight, before final
tightening with the correct size plug wrench.
GLOWPLUG
The role of the glowplug
Glowplug life
Particularly in the case of very high performance
engines,
glowplugs must be regarded as expendable
items. However, plug life can be extended and engine
performance maintained by careful use, i.e.:
Install a plug suitable for the engine.
Use fuel containing a moderate percentage of
nitromethane unless more is essential for racing
events.
Do not run the engine too lean and do not leave the
battery connected while adjusting the needle.
With a glowplug engine, ignition is initiated by the
application of a 1.5-volt power source. When the
battery is disconnected, the heat retained within the
combustion chamber remains sufficient to keep the
plug filament glowing, thereby continuing to keep the
engine running. Ignition timing is 'automatic' : under
reduced load, allowing higher rpm, the plug becomes
hotter and, appropriately, fires the fuel/air charge
earlier; conversely, at reduced rpm, the plug become
cooler and ignition is retarded.
Apart from when actually burned out, a plug may
need to be replaced because it no longer delivers its
best performance, such as when:
When to replace the glowplug
Filament surface has roughened and turned white.
Filament coil has become distorted.
Foreign matter has adhered to filament or plug
body has corroded.
Engine tends to cut out when idling.
Starting qualities deteriorate.
15
INSTALLATION OF THE CARBURETOR
As delivered, the engine has its carburetor
lightly fit into the intake boss. Secure it as
follows.
Loosen the retainer screw, rotate the
carburetor to its correct position and make
sure that it is pressed well down into the
intake boss, compressing the rubber gasket,
before retightening screw.
Rotate the retainer screw gently until it
stops, then tighten a further 60-90˚.
Do not overtighten the screw as this will
damage the carburetor body.
1.
2.
Rotate the retainer nut
gently until it stops. Tighten a further 60-90˚
ENGINE INSTALLATION
Chamfer inside edges of bearers.
Make sure that the vehicle's engine mounting
surfaces are level and in the same plane. Poor
installation may cause distortion of the
crankcase, bearings, etc., resulting in erratic
running and loss of performance.
The recommended screws for securing the
engine are 3mm or 4-40 steel Allen hexagon
socket type.
If existing holes in the engine mount do not align
perfectly with engine mounting lugs, enlarge
them slightly with a needle-file so that screws are
in alignment with the mounting holes.
Chassis
Do not allow bottom
of crankcase to
touch chassis.

16
NOTE:
When spacers are supplied joined in pairs
(see sketch) separate them as shown.
Either face may be placed downwards.
Avoid forcing the screws. Secure with locknuts.
If the bottom of the recoil starter housing would
otherwise touch the car chassis, install the en-
gine mount spacers (optional extra) between
the engine's mounting lugs and the engine
mount. With some vehicles, it may be neces-
sary to make minor trimming modifications to
chassis or body when installing the engine.
Mount Spacer
Separate
Engine Mount
(Optional Extra)
NOTES CONCERNING THE RECOIL STARTER
( 18TZ-TX ONLY)
REMINDER!
Do not attempt to disassemble the recoil starter.
If you do so, the very strong spring inside will be
suddenly ejected. This can be very dangerous.
Do not extend the starter cord more than 40cm
(16"). Do not abruptly release the operating
handle. Allow the cord to rewind smoothly while
still holding the handle.
Pull the operating handle straight out when
starting the engine, so that the cord does not
rub against the vehicle body or engine.
This will help prevent the cord from being
damaged by abrasion or engine heat.
Try to avoid spilling fuel over the starter unit and
its cord. Some fuels have a detrimental effect on
these parts.
The starter prevents the engine from being ro-
tated in the wrong direction.The unit will be
damaged if you attempt to force the flywheel in
the opposite direction (i.e. clockwise when
viewed from the crankshaft end).
In case of the 18TZ-TX
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The somewhat violent changes of vehicle
attitude that occur in off-road running,
combined with the fact that, in buggy type
cars, the fuel tank is often located some
distance from the carburetor, means that
fuel 'head' at the carburettor can vary and
upset running.Therefore,it is recommended
that a muffler pressurized fuel feed system
be used.
PRESSURIZED FUEL SYSTEM
Silencer
Silicone tubing
Before starting the engine, always
check the tightness of all the screws
and nuts especially those of joint and
movable parts such as throttle arm.
Missing retightening the loose
screws and nuts often causes the
parts breakage that is capable of
harming you.
Never run your vehicle without installing the
air cleaner. Dust and dirt that may otherwise
be drawn into the engine will rapidly shorten
its life.
Fuel Tank Connect suitable length
of Silicone tubing between
fuel tank and silencer.
STARTING THE ENGINE &
RUNNING-IN ('Breaking-in)
The following procedure is suitable for these
engines when the O.S. T-1040 tuned silencer
and a fuel containing up to 30% nitrome-
thane are used.
Fill the tank completely with fuel.
Temporarily remove the glowplug to check
that it glows bright red when energized.

18
Glow Plug Igniter
Pliers
Element glows when energized.
Replace the plug when the
element does not glow or is
burnt out.
Turn the needle-valve clockwise slowly until
it stops. This is the fully closed position.
Do not force it to turn further.
Open the Needle-Valve
2 turns from the fully
closed position.
Needle Valve
Open
Close
approx 0.3-0.5mm
In case of the 11K carburetor
Set the throttle-stop screw so that the minimum
throttle opening (idle setting) is approximately
0.3-0.5mm.
approx
1mm
In case of the 11L carburetor
Set the throttle-stop screw so that the minimum
throttle opening (idle setting) is approximately
1.0mm.
Throttle Stop
Screw
Note:
Throttle opening at idle should be checked
before installing an air cleaner.
19
Turn the engine with starter box to draw he
fuel into the engine.
Fuel
Deliver fuel into the carburetor.
Fuel tank side
Now connect glowplug battery lead to heat
the plug filament and start the engine.
When the engine starts, first allow it to
operate in short runs at the very rich starting
settings, with the glowplug battery still
connected and the driving wheels clear of
the ground. The rich mixture will, under
these conditions, provide adequate
lubrication and cooling, indicated by profuse
smoke from the exhaust.
It is vitally important to set
the throttle at the correct
position before starting the
engine. If the engine is
allowed to run with the throttle too far open
under ''no load'' conditions (i.e. with the driving
wheels not in contact with the ground) it will
rapidly over-heat and may be seriously
damaged.
Attention:
Next, disconnect the glowplug battery and try
running the car on the track. If the engine
stalls, open the throttle fractionally, but try to
keep the engine running as rich as possible: if
it stops because of being excessively over-
rich, close the Needle-Valve 30˚ and try again.
Swith on the transmitter and make sure that
each linkage moves correctly.

20
Run the car on the track until one tank of fuel
has been consumed, then close the Needle-
Valve 30˚ and run the car for another full tank
of fuel. Repeat this procedure until 5 more
tanks of fuel have been consumed, during
which time the throttle may be opened for brief
bursts of increased power. If the engine stops
at medium speeds, close the Mixture Screw
45-90˚.
30˚
Needle
The position of the needle-valve
when starting the engine.
Close the needle-valve approx.
30˚ after running the vehicle for
one full tank of fuel.
Repeat this procedure several
times.
30˚
30˚
Warning!
Do not touch rotating
parts, engine and silen-
cer when stopping the
engine as they become
very hot, and contact
with them may result in
a serious burn.
To stop the engine, close the throttle to idle
speed, then shut it off completely with the
trim lever on the transmitter. To cut off the
fuel supply, pinch the fuel delivery tube to
the carburetor.
Note:
If the engine should need to be disassem-
bled (e.g. for cleaning or minor parts re-
placement), it is advisable to return the nee-
dle-valve to the original rich, starting set-
ting and check whether further running-in
time is required before the car is raced
again. In the event of any major working
parts (e.g. piston/cylinder liner assembly)
being replaced or the fuel being changed,
especially to high nitro fuel, the complete
running-in should be repeated.
Fuel
21
Run the vehicle (with throttle fully open) over
the longest available straight course, in order
to observe the model's speed. Next return
the car to the starting point, close the Needle-
Valve 30˚ and repeat the run, taking note of
the improvement in performance. Continue
with further runs, gradually reducing the
Needle-Valve setting and aiming to achieve
the highest straight-line speed. Remember,
however, that, if the Needle-Valve is shut
down too far, the engine will overheat and,
accompanied by visibly diminished exhaust
smoke, the model will lose speed. At this
point, throttle down immediately, stop the
vehicle and reopen the Needle-Valve 30˚.
With the engine running, close the throttle
and allow it to idle for about five seconds,
then reopen the throttle fully. If, at this point,
the engine puffs out an excessive amount of
smoke and the vehicle does not accelerate
smoothly and rapidly, it is probable that the
idle mixture is too rich.
FINAL ADJUSTMENT
Having established the optimum Needle-
Valve setting, check the Mixture Control
Valve setting as follows.
In this case, turn the Mixture Control Valve in
case of the 11L and the Metering Needle in
case of the 11K clockwise 45 degrees. If, on
the other hand, the engine tends to speed up
momentarily and then cut out abruptly when
the throttle is opened,the idle mixture is too
lean. Correct this by turning the Mixture
Control Valve in case of the 11L and the
Metering Needle in case of the 11K counter-
clockwise 45 degrees.

22
With the optimum mixture control position,
light smoke is visible during high speed
running,and the engine revolutions increase
smoothly during acceleration. Remember
that, if the engine is operated with the fuel/air
mixture slightly too lean, it will overheat and
run unevenly. As with all engines, it is
advisable to set both needle-valve and
mixture control screw very slightly on the rich
side of the best rpm setting, as a safety
measure.
If the engine runs too fast with the throttle
closed, the throttle stop screw should be
turned counter-clockwise to allow the throttle
opening to be reduced.
Finally, beyond the nominal break-in period,
a slight readjustment toward a leaner needle
setting may be required to maintain
performance.
Warning!
Mixture adjustments (whether via the
Mixture Control Valve, or the Needle-Valve)
cannot be made accurately under 'no-load'
conditions, which, in any case, are not
advised, since such operation carries the
risk of seriously damaging the engine
through over-revving and overheating.
Carry out adjustments patiently, under actual
running conditions, until the engine responds
quickly and positively to the throttle control.
CARBURETOR CLEANLINESS
The correct functioning of the carburetor
depends on its small fuel orifices remaining
clear.
REALIGNMENT OF METERING NEEDLE AND
MIXTURE CONTROL VALVE
In the course of making carburetor adjust-
ments, it is just possible that the Metering Nee-
dle and the Mixture Control Valve may be inad-
vertently screwed in or out too far and thereby
moved beyond its effective adjustment range.
23
Mixture Control Valve
Carburetor Body
Slide Valve
Carburetor Body
Metering Needle
Rotate the Metering
Needle until its slotted
head is flush with the
ball link body. This is the
standard position.
Ball Link
First rotate the Mixture
Control Valve until its slotted
head is flush with the
carburetor body. Then screw
the valve in exactly 0.5 turn.
This is the standard position.
The basic positions can be found by rotating
the Metering Needle until its slotted head is
flush with the ball link body.
Rotate the Mixture
Control Valve until its
slotted head is flush with
the ball link body. This is
the standard position.
Mixture Control Valve
Carburetor Body
Throttle Lever
In case of the 11K carburetor
In case of the 11L carburetor

24
CARE AND MAINTENANCE
1.
2.
3.
The minute particles of foreign matter, that are
present in any fuel may, by accumulating and
partially obstructing fuel flow, cause engine
performance to become erratic and unreliable.
O.S. 'Super-Filters' (large and small) are available,
as optional extras, to deal with this problem.
One of these filters installed to the pickup tube
inside your refueling container, will prevent the entry
of foreign material into the fuel tank. It is also
recommended that a good in-line filter be installed
between the tank and carburetor.
Do not forget to clean the filters regularly to remove
dirt and lint that accumulate on the filter screens.
Also, clean the carburetor itself occasionally.
At the end of each operating session, drain out any
fuel that may remain in the fuel tank.
Afterwards,energize the glow-plug and try to restart
the engine, to burn off any fuel that may remain
4. Then, inject some after-run oil into the engine, and
rotate the engine with an electric starter for 4 to 5
seconds to distribute the oil to all the working
parts.
inside the engine. Repeat this procedure until the
engine fails to fire. Do this while the engine is still
warm.
Note:
5.
Do not inject after-run oil into the carburetor as
this may cause the O-rings inside the carburetor
to deteriorate. These procedures will reduce the
risks of starting difficulties or corrosion after a
period of storage.
Finally, when cleaning the exterior of the engine,
use methanol or kerosene. Do not use gasoline or
any solvent that might damage the silicone fuel
tubing.
Caution:
The rear crankshaft bearing of this engine uses a
special plastic retainer. If the front housing needs
to be heated to remove or replace the bearing, do
not allow the bearing to exceed 120˚C (248˚F),
otherwise it may be damaged and rendered
unserviceable.
25
Installing Dust Caps
When storing the engine, install the cap on
the exhaust port, carburetor, etc. to prevent
dust from entering the engine.
Dirt and dust may lodge in marked places.
CHECKING THE ENGINE
If the engine suffers a loss of performance
after a long period of running it may be due to
the wearing of parts. It is suggested that the
worn parts be replaced when the following
symptoms are detected.
Engine sound changes and easily overheats.
Power has dropped considerably.
Idle is unstable and/or engine tends to stop
at idle.
In most cases, ball bearings, cylinder & piston
assembly, connecting rod and/or crankcase have
become worn out or abnormal. Check the
parts carefully and replace them if necessary.

26
TROUBLE SHOOTING Symptom
Cause Corrective action
Engine fails to fire.
Fuel tank is empty.
Fuel not reaching the engine.
Fill the tank with fuel and repeat
Priming procedure.
Glowplug element is burnt out.
Glowplug battery discharged
Replace glowplug.
Recharge or replace the battery.
Clogged fuel filter
Air cleaner and silencer inside is dirty.
Clean or replace fuel filter.
Replace cleaner element and clean inside silencer.
Over priming Remove glowplug and pump excess fuel.
Fuel tubing is disconnected. Connect fuel tubing securely.
Fuel tubing is kinked, split or has a hole. Check the tubing carefully and replace if necessary.
Incorrect servo linkage Connect correctly after setting servo at neutral.
Reverse rotating direction of starter box. Mare sure it rotates counter clockwise seen
from crankshaft side.
Recoil starter slips. Inject cleaner spray into starter cord crevis
on the body.
27
Symptom
Cause Corrective action
Engine fires intermittently but does not run.
Insufficient fuel in the tank. Fill the tank with fuel.
Deteriorated glowplug Replace glowplug.
Clogged fuel filter
Air cleaner and silencer inside is dirty.
Clean or replace fuel filter.
Replace cleaner element and clean inside silencer.
Engine overheated Wait until engine is cool.
Incorrect clutch release Adjust the tension of clutch spring.
Starting battery disconnected too soon. Do not disconnect plug battery and wait until
r.p.m. become stable.
Vibration causing air bubbles in fuel. Install O rings to the tank screws to
prevent bubbles.

28
Symptom
Cause Corrective action
Symptom
Cause Corrective action
Unstable idle
Unsuitable glowplug Use suggested glowplug in the instructions.
Unsuitable fuel Do not use extremely high nitro
or low oil content fuel.
Extremely light flywheel Add suitable load.
Silencer is disconnected or has play Install silencer securely.
Not reaching expected peak r.p.m.
Insufficient warming up or running-in. Set the needle only after warming up.
Complete running-in.
Silencer or manifold is not securely connected
or disconnected.
Replace seal ring.
Check the connections and secure them.
Fuel tubing from tank is split or broken. Replace the tubing.
29
Symptom
Cause Corrective action
Symptom
Cause Corrective action
Poor response
Deteriorated glowplug Replace glowplug.
Incorrect carburetor settings Readjust low r.p.m. range with metering
needle and mixture control valve.
Incorrect setting of transmitter Exponential function.
Check the transmitter setting.
Poor r.p.m. drop
Throttle position open too far. Close metering needle to adequate position
to lower idle r.p.m.
carburetor not fully seated Install carburetor securely.
Incorrect linkage Make sure that throttle servo does not interfere
servo linkage.
Metering needle closed too far. Open the metering meedle a little.

30
C.M3x16
1
2
3
5
4
6
7
8
9
10
11
12
14
13
15
C.M2.6x7
MAX-18TZ(P)-T ENGINE EXPLODED VIEW
Type of screw
C...Cap Screw M...Oval Fillister-Head Screw F...Flat Head Screw N...Round Head Screw S...Set Screw
31
MAX-18TZ(P)-T ENGINE PARTS LIST
The specifications are subject to alteration for improvement without notice.
21914010 21914110 21913010 21816000 21817000 21915000 21982000 25381701 23731000 21911010 21931000 21912010 21824000 21917000 23763000 71641300 21427200
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15
Outer Head Inner Head Cylinder & Piston Assembly Piston Pin Piston Pin Retainer (2pcs.) Connecting Rod Carburetor Complete (Type 11K) Carburetor Retainer Assembly Crankshaft Ball Bearing (Front) Crankcase Crankshaft Ball Bearing (Rear) Crankshaft Gasket Set Cover Plate Screw Set Glow Plug P3 Exhaust Seal Ring
Description
Code No.
No.

32
C.M3x16
1
2
3
5
4
6
7
8
11
12
14
13
15
C.M2.6x7
910
16
17
MAX-18TZ-T ENGINE EXPLODED VIEW
Type of screw
C...Cap Screw M...Oval Fillister-Head Screw F...Flat Head Screw N...Round Head Screw S...Set Screw
33
MAX-18TZ-T ENGINE PARTS LIST
The specifications are subject to alteration for improvement without notice.
21914010 21914110 21913010 21816000 21817000 21915000 21884010 25381701 20810007 21458000 23731000 21911010 21931000 21912020 21824000 21917000 23763000 71641300 21427200
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17
Outer Head Inner Head Cylinder & Piston Assembly Piston Pin Piston Pin Retainer (2pcs.) Connecting Rod Carburetor Complete (Type 11L) Carburetor Retainer Assembly Propeller Nut Drive Hub Crankshaft Ball Bearing (Front) Crankcase Crankshaft Ball Bearing (Rear) Crankshaft Gasket Set Cover Plate Screw Set Glow Plug P3 Exhaust Seal Ring
Description
Code No.
No.

34
C.M3x16
1
2
3
5
4
6
7
8
11
12
14
13
15
C.M2.6x7
910
16
MAX-18TZ(S)-T ENGINE EXPLODED VIEW
Type of screw
C...Cap Screw M...Oval Fillister-Head Screw F...Flat Head Screw N...Round Head Screw S...Set Screw
35
MAX-18TZ(S)-T ENGINE PARTS LIST
The specifications are subject to alteration for improvement without notice.
21914010 21914110 21913010 21816000 21817000 21915000 21884010 25381701 20810007 23731000 21911010 21931000 21912030 21824000 21917000 23763000 71641300 21427200
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16
Outer Head Inner Head Cylinder & Piston Assembly Piston Pin Piston Pin Retainer (2pcs.) Connecting Rod Carburetor Complete (Type 11L) Carburetor Retainer Assembly Propeller Nut Crankshaft Ball Bearing (Front) Crankcase Crankshaft Ball Bearing (Rear) Crankshaft Gasket Set Cover Plate Screw Set Glow Plug P3 Exhaust Seal Ring
Description
Code No.
No.

36
C.M3x16
1
2
3
5
4
6
7
8
11
12
14
13
15
910
19
16 17
18
M.+M2.6x7
M.+M2.6x7
18-1
18-2
MAX-18TZ-TX ENGINE EXPLODED VIEW
Type of screw
C...Cap Screw M...Oval Fillister-Head Screw F...Flat Head Screw N...Round Head Screw S...Set Screw
37
MAX-18TZ-TX ENGINE PARTS LIST
The specifications are subject to alteration for improvement without notice.
21914010 21914110 21913010 21816000 21817000 21915000 21884010 25381701 20810007 21458000 23731000 21911010 21931000 21912040 21824000 21922000 21901800 73008000 73008100 73008200 21923000 71641300 21427200
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18
18-1 18-2
19
Outer Head Inner Head Cylinder & Piston Assembly Piston Pin Piston Pin Retainer (2pcs.) Connecting Rod Carburetor Complete (Type 11L) Carburetor Retainer Assembly Propeller Nut Drive Hub Crankshaft Ball Bearing (Front) Crankcase Crankshaft Ball Bearing (Rear) Crankshaft Gasket Set Starting Shaft Rear Adaptor No.N1 Recoil Starter Assembly No.N1 Recoil Starter Body No.N1 One-way Clutch Screw Set Glow Plug P3 Exhaust Seal Ring
Description
Code No.
No.

38
11K CARBURETOR EXPLODED VIEW
Type of screw
C...Cap Screw M...Oval Fillister-Head Screw
F...Flat Head Screw N...Round Head Screw S...Set Screw
S.M3x3
1
1-1
1-2
2
2-1
2-2
3
4
8
9
10
56
6-1
7
3-1
39
The specifications are subject to alteration for improvement without notice.
11K CARBURETOR PARTS LIST
1
1-1
1-2
2
2-1
2-2
3
3-1
4
5
6
6-1
7
8
9
10
Description
Code No.
No.
22615000
22781800
27881820
21982700
21982620
27881820
21285901
21982100
21982210
21982540
21982520
23818430
21881950
22781800
Carburetor Rubber Gasket
Ball Link No.5
Dust Cover
Metering Needle Assembly
Slide Valve
No.14 Universal Nipple Assembly
Carburetor Body (w/Thermo Insulator)
"O" Ring (2pcs.)
Needle Valve Assembly
Throttle Stop Screw
"O" Ring(S) (2pcs.)
"O" Ring(L) (2pcs.)
Mixture Control Valve Assembly
"O" Ring(S) (2pcs.)
Thermo Insulator
21982900
22781800 "O" Ring(S) (2pcs.)