O.S. engine max-12TZ 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.
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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 ABOUTYOUR O.S.ENGINE
ENGINE CONSTRUCTION, NOTES WHEN
APPLYING AN ELECTRIC STARTER
ABOUT THE ENGINE
TOOLS, ACCESSORIES, etc.
BASIC ENGINE PARTS
INSTALLATION OF THE STANDARD
ACCESSORIES, CARBURETOR
CONTROLS 11H, 11H(B)
GLOWPLUG, INSTALLATION
2-5
6-7
8
12-13
14-15
16-19
STARTING THE ENGINE & RUNNING-IN
('Breaking-in)
FINAL ADJUSTMENT
CARE AND MAINTENANCE,
CHECKING THE ENGINE
TROUBLE SHOOTING
ENGINES, CARBURETORS EXPLODED
VIEWS &PARTS LIST
O.S. GENUINE PARTS & ACCESSORIES
THREE VIEW DRAWING
38-39
9-11
40
24-25
26-29
30-37
20-23

2
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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 ABOUTYOUR 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
whichmightigniteit.Donot
smokeorallowanyoneelse
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.
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•

4
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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.
Install 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.
NOTES
•
•
•
•
•
•
5
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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.
•
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.

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
NOTESWHEN 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.

8
Standard accessories
Glow Plug P6 T-type head
(Turbo head) 1piece
Exhaust Seal Ring 1piece
(Hot Type)
ABOUT THE ENGINE
NOTE
These engines are rear exhaust
engines designed expressly for 1/10
class R/C touring cars and stadium
trucks. T-Type P6 plus is supplied with
the engine. Also, dual adjustable
carburetor is supplied.
The engines develop enormous torque
from the low r.p.m. and offer improved
fuel consumption and durability.
Big diameter heatsink head has
improved cooling efficiency.
As delivered, the engine has the
carburetor lightly fit into its intake.
Secure it changing its angle and
outer head position according to
the car chassis.
This manual handles the following two versions.
MAX- 12TZ SERIES INSTRUCTIONS
Carburetor Reducer 6.5mm (Gray) 1piece
(w/ "O" Ring)
MAX-12TZ(P)-T3 (3 port version)
with 11H carburetor
MAX-12TZ(P)-T5 (5 port version)
with 11H(B) carburetor
For
MAX- 12TZ(P)-T5 only
9
FUEL FILTER
To be installed in the fuel line
between fuel tank and carburetor
to prevent dust from entering the
carburetor.
GLOWPLUG IGNITER
Commercialy available handy
glowplug heater in which the
glowplug battery and battery
leads are integrated.
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.
TOOLS, ACCESSORIES, etc.
The following items are necessary for operating the engine.
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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.
STARTER BOX
For starting the engine.

10
FUEL PUMP
For filling the fuel tank, a simple,
polyethylene "squeeze" bottle,
with a suitable spout, is required.
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.
TOOLS
HEX SCREWDRIVER
SCREWDRIVER
Necessary for engine installation.
1.5mm, 2mm, 2.5mm, 3mm
Necessary for carburetor adjustments.
No.1, No.2, etc
LONG SOCKETWRENCH 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.
SOCKET DRIVER
It is required to tighten and loosen the
carburetor retainer nut. Opposite side distance
of 6mm
11
Outer Head
Crankcase
Mounting Lugs
Exhaust
Cover Plate
Carburetor
Type 11H
Crankshaft
BASIC ENGINE PARTS
Crankshaft Ball Bearing (Front) MAX-12TZ(P)-T3

12
Install the exhaust seal
ring supplied.
Exhaust
Seal Ring
Glowplug
INSTALLATION OF THE
STANDARD ACCESSORIES
Installing the glow plug.
Insert P6 plug supplied
into heatsink-head care-
fully, making sure that it is
not cross-threaded before
tightening firmly.
(All the O.S. T-Type plugs
including the P6 are not
supplied with a washer.)
About the Head Gasket
These engines are equipped with two head
gaskets of 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 with both gaskets or removing the
0.1mm gasket.
When low nitromethane content fuel is used,
try to run the engine removing the 0. 2mm
gasket.
Installing the carburetor reducer
5.5mm (Black) bore reducer is installed on
both the 12TZ(P)-T3 and 12TZ(P)-T5
carburetor.
Extra 6.5mm bore reducer is supplied with
the 12TZ(P)-T5 only. With this reducer
installed, more power can be obtained, while
engine adjustment becomes a little critical
13
CARBURETOR CONTROLS 11H,
The Needle-Valve(Adjusted at the factory):
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
(Adjusted at the factory):
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
Carburetor Reducer
Ball Link No.5
Dust Cover
11H(B)

14
Since the compatibility of the glowplug and fuel
may have a marked effect on performance and
reliability, it is suggested to use the O.S. P6
plug when it is necessary to replace. 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
themslightlywithaneedle-filesothatscrewsare
in alignment with the mounting holes.
Chassis
Do not allow bottom
of crankcase to
touch chassis.

16
STARTINGTHE ENGINE & RUNNING-IN ('Breaking-in)
PRESSURIZED FUEL SYSTEM
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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 break-
age 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.
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.
Lay the chassis on a stand and start the
engine so that the tiers may not be in
contact with the ground.
Running- in is a procedure for an engine to
come close to actual running conditions
(fuel, r.p.m., engine temperature, etc.).
Excessively rich running and prolonged
low speed running mean nothing. Prolon-
ged low speed running and low tempera-
ture running may result in the oil in the fuel
being gelled and piston/liner being agglu-
tinated.
Try to make time to run the car at full throttle.
Lengthen full throttle running time gradually.
When the car can run full throttle with rich
mixture at the straight, close the needle-valve
a little. Repeat this procedure until the car runs
at the maximum speed at the latter straight
course.
17
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.
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 until it stops. This
is the fully closed position. Do not force it to turn
further.
Metering needle and mixture control valve
are set at basic position. (Refer to P23.)
Needle Valve
Open Close (clockwise)
approx 0.5mm
The carburetor is set as shown below at the
factory. Start the engine as it is.
The needle-valve is set approx. 1-3/4 turns
opened from the fully closed position.
Throttle is set approx. 0.5mm open.
Approx. 0.5mm open
factory setting with the
reducer removed

18
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
allowedtorunwiththethrottle
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 15˚and try again.
Swith on the transmitter and make sure that
each linkage moves correctly.
19
Run the car on the track until one tank of fuel
has been consumed, then close the Needle-
Valve 15˚and run the car for 3 to 5 full tanks
of fuel. Repeat this procedure until approx.2
liters of fuel have been consumed, during
whichtimethethrottlemaybeopenedforbrief
bursts of increased power.If the engine stops
at medium speeds, close the Mixture Screw
45˚.
Needle
The position of the needle-valve
when starting the engine.
Close the needle-valve approx.
15˚after running the vehicle for
3 to 5 full tanks of fuel.
Repeat this procedure until
approx. 2 liters of fuel have
been consumed.
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
disassembled (e.g. for cleaning or minor
parts replacement), it is advisable to return
the needle-valve to the original rich,
starting setting and check whether further
running-in time is required before the car is
raced again. In the event of any major work-
ing parts (e.g. piston/cylinder liner assem-
bly) being replaced or the fuel being
changed, especially to high nitro fuel, the
complete running-in should be repeated.
Fuel

20
FINAL ADJUSTMENT
Throttle
Stop Screw
Needle Valve
Metering
Needle
Open Close Close
Open
Needle Valve Metering Needle
More fuel Less fuel More fuel Less fuel
Run the vehicle (with throttle fully open) over
thelongest available straightcourse,in order
to observe the model's speed. Next return
thecartothestartingpoint,closetheNeedle-
Valve 15˚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,stopthevehicleandreopenthe
Needle-Valve 15˚.
Final adjustment should be carried out only after
the running-in has been completed.
21
Warning!
Mixture adjustments (whether via the
Metering Needle, 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.
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.
Carry out adjustments patiently, under actual
running conditions, until the engine responds
quickly and positively to the throttle control.
In this case, turn the Metering Needle
clockwise 15˚. 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 Metering Needle
counter-clockwise 15˚.

22
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
maximum performance.
With the optimum mixture control position,
light smoke is visible during high speed
running,and the engine rpm increases
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 the needle-valve and
metering needle slightly on the rich side of
the best rpm setting, as a safety measure.
23
REALIGNMENT OF METERING NEEDLE AND
MIXTURE CONTROL VALVE
In the course of making carburetor
adjustments, it is just possible that the
Metering Needle and the Mixture Control
Valve may be inadvertently screwed in or out
too far and thereby moved beyond its
effective adjustment range.
The basic positions can be found by rotating
the Metering Needle until its slotted head is
flush with the ball link body.
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
basic position.
Ball Link
Rotate the Mixture Control
Valve until its slotted head is
flush with the carburetor
body. This is the basic
position.

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.
CHECKINGTHE 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,connectingrodand/orcrankcasehave
become worn out or abnormal. Check the
parts carefully and replace them if necessary.
(Optional extra)

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.
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
MAX-12TZ (P)-T3 ENGINE EXPLODEDVIEW
Type of screw
C...Cap Screw M...Oval Fillister-Head Screw
F...Flat Head Screw N...Round Head Screw S...Set Screw
C.M3x16
1
2
3
5
4
6
7
8
9
10
11
12
14
13
15
C.M2.6x7
31
MAX-12TZ (P)-T3 ENGINE PARTS LIST
The specifications are subject to alteration for improvement without notice.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
21534000
21534100
21533000
21536000
21817000
21535000
21538000
25381701
22631020
21531000
21931000
21532000
21531400
21917000
23763000
71641600
21427200
Outer Head (Blue)
Inner Head
Cylinder & Piston Assembly
Piston Pin
Piston Pin Retainer (2pcs.)
Connecting Rod
Carburetor Complete (Type 11H)
Carburetor Retainer Assembly
Crankshaft Ball Bearing (Front)
Crankcase
Crankshaft Ball Bearing (Rear)
Crankshaft
Gasket Set
Cover Plate
Screw Set
Glow Plug P6
Exhaust Seal Ring
Description
Code No.
No.

32
11H 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
1-11-2
2
2-1
2-2
3
4
8
9
10
56
7-1
7
3-1
3-1
4-1
11
33
1
1-1
1-2
2
2-1
2-2
3
3-1
4
4-1
5
6
7
7-1
8
9
10
11
21982600
27881820
22781800
21982970
27881820
21881950
71533055
22615000
21982620
22781800
21538100
21982200
21538500
22781800
21982520
23818430
21982900
22615000

The specifications are subject to alteration for improvement without notice.
11H CARBURETOR PARTS LIST
Description
Code No.
No. Mixture Control Valve Assembly
"O" Ring(L) (2pcs.)
"O" Ring(S) (2pcs.)
Needle Valve Assembly
"O" Ring (2pcs.)
No.14 Universal Nipple Assembly
Carburetor Reducer (5.5mm, Black)
"O" Ring
Throttle Stop Screw
"O" Ring(S) (2pcs.)
Carburetor Body (w/Thermo Insulator)
Slide Valve
Metering Needle Assembly
"O" Ring(S) (2pcs.)
Dust Cover
Ball Link No.5
Thermo Insulator
Carburetor Rubber Gasket

34
MAX-12TZ (P)-T5 ENGINE EXPLODEDVIEW
Type of screw
C...Cap Screw M...Oval Fillister-Head Screw
F...Flat Head Screw N...Round Head Screw S...Set Screw
C.M3x16
1
2
3
5
4
6
7
8
9
10
11
12
14
13
15
C.M2.6x7
35
MAX-12TZ (P)-T5 ENGINE PARTS LIST
The specifications are subject to alteration for improvement without notice.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Outer Head (Silver)
Inner Head
Cylinder & Piston Assembly
Piston Pin
Piston Pin Retainer (2pcs.)
Connecting Rod
Carburetor Complete (Type 11H (B))
Carburetor Retainer Assembly
Crankshaft Ball Bearing (Front)
Crankcase (Black)
Crankshaft Ball Bearing (Rear)
Crankshaft
Gasket Set
Cover Plate
Screw Set
Glow Plug P6
Exhaust Seal Ring
Carburetor Reducer 6.5mm (Gray)
Description
Code No.
No. 21534010
21534100
21533010
21536000
21817000
21535000
21538010
25381701
22631020
21531010
21931000
21532010
21531400
21537000
23763000
71641600
21427200
71533055

36
11H (B) 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
1-11-2
2
2-1
2-2
3
4
8
9
10
56
7-1
7
3-1
3-1
4-1
11
37
The specifications are subject to alteration for improvement without notice.
11H (B)CARBURETOR PARTS LIST
1
1-1
1-2
2
2-1
2-2
3
3-1
4
4-1
5
6
7
7-1
8
9
10
11
21982600
27881820
22781800
21982970
27881820
21881950
71533055
22615000
21982620
22781800
21538110
21982200
21538500
22781800
21982520
23818430
21982900
22615000
71533065

Description
Code No.
No. Mixture Control Valve Assembly
"O" Ring(L) (2pcs.)
"O" Ring(S) (2pcs.)
Needle Valve Assembly
"O" Ring (2pcs.)
No.14 Universal Nipple Assembly
Carburetor Reducer (5.5mm, Black)
"O" Ring
Throttle Stop Screw
"O" Ring(S) (2pcs.)
Carburetor Body (Black, w/Thermo Insulator)
Slide Valve
Metering Needle Assembly
"O" Ring(S) (2pcs.)
Dust Cover
Ball Link No.5
Thermo Insulator
Carburetor Rubber Gasket
Carburetor Reducer (6.5mm, Gray)

38
RACING ENGINE PARTS
(72106420)
(72106172)
(72106172)
(72103051)
(72103056)
(72103071)
(72103076)
(72106400)
(72106172)
(72106410)
(72106172)
(72106310)
(22826140)
(72106311)
(72106042)
(72106320)
(22826140)
(72106321)
(72106042)
(71641600)
P6
(71641700)
P7
(71641800)
P8
M1001
M1010
(72103180)
T-1040 L52
T-1040 R52
T-1040 L70
T-1040 R70
O.S. GENUINE PARTS & ACCESSORIES
O.S. Glow Plug Exhaust Manifold Assembly
Manifold Spring
Tuned Silencer
Manifold Spring
Manifold Spring
Manifold Spring
M1001SC
M1011SC
T-1040SC L52
Tuned Silencer Assembly T-1040SC R52
Tuned Silencer Assembly
Tuned Silencer Body
Exhaust Seal Ring (2pcs.)
Joint Spring (3pcs.)
Tuned Silencer Body
Exhaust Seal Ring (2pcs.)
Joint Spring (3pcs.)
Super
JointTube 15
(72103310)
Left side exhaust,
Joint tube type
Right side exhaust,
Joint tube type
Joint tube type Spring connect type
Left side exhaust,
Spring connect type
Right side exhaust,
Spring connect type
Left side exhaust
Right side exhaust
Left side exhaust
Right side exhaust
Left side exhaust Right side exhaust
39
(21427200)
(72412000)
(72412100)
(72412200)
(72413000)
(72413200) (71521000)
(79871020)
(73300305)
(73301612)
RACING ENGINE PARTS
(72106500)
(72106510)
(72106310)
(72106320)
(72106400)
(72106410)
(21427200)
Dust Cap Set
3mm
16mm
M2.6x7
(2pcs.)
Super Air Cleaner 203 Assembly
203 Filter Element (4pcs.)
(5pcs.)
(3pcs.)
Cap Screw Set
(10pcs.)
The specifications are subject to alteration for improvement without notice.
T-1040SC L52
Tuned Silencer Assembly
T-1040SC R52
Tuned Silencer Assembly
Super Air Cleaner 202 Assembly
202 Cleaner Body
202 Filter Element (4pcs.)
Long SocketWrench
With Plug Grip
Exhaust Seal Ring
T-1040SC L52 Complete Set M1001SC
Exhaust Manifold Assembly
T-1040SC R52 Complete Set M1011SC
Exhaust Manifold Assembly
(2pcs.)
Exhaust Seal Ring
O.S. GENUINE PARTS & ACCESSORIES
Off-road Type
On-road Type