O.S. engine MAX-105HZ-R User manual

OS ene
MAXx-105HZ-R
Integrated with O.S. Demand Regulator System
INSTRUCTION MANUAL
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.
e Keep these instructions in a safe place so that you
may readily refer to them whenever necessary.
e It is suggested that any instructions supplied with
the model, radio control equipment, etc., are
accessible for checking at the same time.
OS creme CONTENTS
SAFETY INSTRUCTIONS AND
WARNINGS ABOUT YOUR O.S. ENGINE --------- 2-5 STARTING ---------------------------- 25-28
NOTES
ON
INSTALLING
COOLING-FAN
ANDCLUTCH
----
6-7
RUNNING-IN
("Breaking-in")
----------------
29
NOTES WHEN APPLYING AN ELECTRIC STARTER, ADJUSTMENT ------------------------ 30-34
INSTALLATION OF THROTTLE SERVO-------- 8-9
ADJUSTMENT CHART -------------------- 35
NOTES ON HEATING THE GLOW PLUG ---------- 10
INTRODUCTION, ENGINE PARTS NAME ---- 11-12 CARE AND MAINTENANCE Sas su spissa 36-37
BEFORE STARTING, TROUBLE SHOOTING -------------------- 38-41
INSTALLATION OF THE ENGINE ---------- 13-16 ENGINE EXPLODED VIEW & PARTS LIST ------ 42-43
INSTALLATION OF THE CARBURETOR EXPLODED VIEW & PARTS LIST----- 44-45
STANDARDACCESSORIES -------------- 17-18
O.S. GENUINE PARTS & ACCESSORIES ---- 46-47
ABOUT THE REGURETOR ,
ABOUT THE SILENCER AND PLUMBING ---- 19-21 THREE VIEW DRAWING ------------------- 48
GLOWPLUGS, CARBURETOR CONTROLS ----- 22-24

SAFETY INSTRUCTIONS AND WARNINGS ABOUT YOUR O.S. ENGINE
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.
Hi The advice which follows is grouped under two headings according to the
degree of damage or danger which might arise through misuse or neglect.
These cover events which These cover the many other
might involve serious (in possibilities, generally less obvious
extreme circumstances, even sources of danger, but which, under
fatal) injury. certain circumstances, may also
cause damage or injury.
° Never touch, or allow any ° Never operate your engine in an en-
object to come into contact closed space. Model engines, like auto-
with, the rotating parts. mobile engines, exhaust deadly carbon-
monoxide. Run your engine only in an
i . . open area.
e Model engine fuel is poison-
ous. Do not allow it to come
into contact with the eyes or Modël engines: generate
mouth. Always store it in a considerable heat. Do not
clearly marked container and touch any part of your
out of the reach of children. engine until it has cooled.
Contact with the muffler
(silencer), cylinder head or
exhaust header pipe, in
particular, may result in a
serious burn.
e 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.

e This engine was designed for model
helicopters. Do not attempt to use it for any
other purpose.
e Mount the engine in your model securely, fol-
lowing the manufacturers’ recommendations,
using appropriate screws and locknuts.
e Install an effective silencer (muffler). Frequent
close exposure to a noisy exhaust (especially
in the case of the more powerful high-speed
engines) may eventually impair your hearing
and such noise is also likely to cause
annoyance to others over a wide area.
e Check the linkage to the throttle arm before
each flight.
e Avoid sudden high r.p.m. immediately after the
engine is started, as the clutch will engage and
you may be struck by the rotor.
e Take care that loose clothing (ties, shirt sleeves,
scarves etc.) do not come into contact with the
rotor. Do not carry loose objects (such as pen-
cils, screwdrivers, etc.) in a shirt pocket from
where they could fall through the rotor disc.
For their safety, keep all onlookers (especially
small children) well back (at least 20 feet or 6
meters) when preparing your model for flight. If
you have to carry the model to the take-off point
with the engine running, be especially cautious.
Hold the rotor securely and keep well clear of
spectators.
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 restart when turned
over WITHOUT the glowplug battery being
reconnected. Remember this if you wish to
avoid the risk of accidents.
e After starting the engine, carry out any needle-
valve readjustments after stopping the rotor by
closing the throttle to the lowest r.p.m..
Stop the engine before attempting to make
other adjustments to the carburetor.
e Use an electric starter. The wearing of safety
glasses is also strongly recommended.
Press the rotor head down securely.
e Take care that the glow plug clip or battery
leads do not come into contact with rotating
parts.
e Adjust the throttle linkage so that the engine
stops when the throttle stick and trim lever on
the transmitter are fully retarded. Alternatively,
the engine may be stopped by cutting off the
fuel supply. Never try to stop the engine
physically.

OS ave
Notes on installing cooling fan and clutch
Do not use a tool which locks piston
when installing a cooling-fan and
clutch, or top of the piston may be
damaged. Also, do not insert a screw
driver or the similar into the exhaust
port.
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It is recommended to use Crankshaft
Clamp 91/105 (Code No.71530520)
available as an optional tool.
With this engine, the cover plate cannot
be removed when the piston is at BDC
due to engine construction.
When it is required to remove the cover
plate, be sure to position the piston at
TDC.
Ô Scone
Notes on installing cooling fan and clutch
Do not grip the engine mounting
beams with a vise, or the crankcase
will be distorted which will result in
engine breaking.
Beam Mount

OS avez
NOTES WHEN APPLYING AN ELECTRIC STARTER
Because of the initial tightness, of the
piston/sleeve assembly a standard
electric starter may have difficulty in
rotating the engine when cold, before
it has been adequately run-in. In this
case, use a high-torque type 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 from
getting into your eyes.
OS. come
Linking the throttle servo to the carburetor
Link the throttle servo to the carburetor using the throttle lever supplied.
Throttle control rod A and B should be equal length. Set the linkage so that
the servo output lever and throttle lever are parallel when the throttle stick on
the transmitter is at middle position. Installation hole intervals on the F lever
and on the J lever are different. Decide the lever to use according to the servo
used. Be sure to cut off the unused levers to avoid any interference.
B

@ Sama
Note on heating the glow plug
The heatsink head on the engine is
treated with an anodized finish which
does not conduct current. Therefore,
when heating a glow plug, connect
one lead to the glow plug and the
other to the head or cover plate
retaining screw.
OS. creme
The MAX-105HZ-R has been developed expressly for 90
size helicopter models, equipping the O.S. regulator
system. It's mounting dimension is the same as the
conventional 90 size engines, while the displacement is
increased by 15%. Also, the conventional 90 size models
gear ratio can be used with this engine without any
modification. The regulator system ensures an always
steady fuel supply which is required for 3D flights which
require repeated vigorous attitude changes as well as for
F3C flights which require severe mixture control.
With this system, the fuel tank is pressurized by pressure
generated in the crankcase. The fuel sent by pressure is
regulated by the regulator installed just ahead of the
carburetor, then sent into the engine. The new silencer
PowerBoost 105 has also been developed to match the
105HZ-R, While the conventional 90 size silencers can also
be used with the 105HZ-R.
A large velocity stack is supplied with the engine to be
installed on the 61G carburetor. Cool fresh air is
conducted to the carburetor intake so that the engine can
develop ideal power characteristics.
When the governor function from Futaba GY-701 or GY-
750 gyro is employed, the Futaba BPS-1 Back Plate
Sensor can be installed in a cell on the back plate. By
employing the governor function, more stable flight can
be achieved.
11
Example
INTRODUCTION
The upper left back plate retaining screw may be used for
a battery ground terminal when connecting the glowplug
battery.
Standard accessories
e Glow Plug No.8
e Velocity Stack
Set Screw M3x3
sD
SP
* Head Gasket (0.1mm)
e Check Valve
e Head Gasket (0.2mm)
NX
NOTE
As delivered, the engine has the carburetor
lightly fit into the intake. Secure it changing
the angle according to the model.

OS. creme ENGINE PARTS NAME
Glowplu
Heatsink Head E
Throttle Lever
Carburetor
Typr 61G
High Speed
Z Needle Valve
Mixture Control
Valve Stopper
Reguretor
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W
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Thrust
Washer
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Cover
Plate
Medium
Speed
x
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Needle
Valve
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Crankcase
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Carburetor Rubber Gasket
Propeller nut
Crankshaft
12
OS amome BEFORE STARTING
Tools, accessories, etc.The following items are In case of 1.5volt dry cell
necessary for operating the engine.
E items necessary for starting
Glow Plug
O.S. No.8 is supplied with the engine.
Battery leads ©
These are used to conduct current Make sure glowplug element
from the battery to the glowplug. glows bright red inside room
Basically, two leads, with clips, are or shadow.
required, but, for greater conve-
nience, twin leads with special
glowplug connectors, as shown on Battery leads Hexagon starting shaft
the right, are commercially available. This shaft mounted on an
electric starting motor is driven
Glowplug battery
into the shaft cup to turn the
The power source for heating the glowplug may be .
either a large heavy-duty 1.5volt dry cell, Ni-cd battery engine.
or glowplug Igniter.
Á Electric starter and starter
— battery
1.5 volt dry cell An electric starter is recom-
glowplug Igniter mended for starting.
13
Starter

@ Saam
Fuel
Select, by practical tests, the most suitable fuel from among
the best quality fuels available in your country for helicopter
use. For the best throttle response, a fuel containing 10% to
30% nitromethane is preferable. Lubricants may be either
castor-oil or a suitable synthetic oil (or . a blend of both)
provided that they are always of top quality. For consistent
performance and long engine life, it is essential to use fuel
containing AT LEAST 18% lubricant by
volume. Some fuels containing coloring
additives tend to deterriorate and may
adversely affect running qualities. If in
doubt compare to a fuel known to be good.
Reminder!
Model engine fuel is poisonous. Do notallow
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.
OS ane
E TOOLS
O.S. SPEED Driver Tools
14
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O.S. SPEED Plug Wrench
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Phillips Screwdriver
No.1, No.2, etc.
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15
Fuel Pump
Alternatively, one of the purpose-made
manual or electric fuel pumps may be
used to transfer fuel directly from your
fuel container to the fuel tank.
O.S. Super Filter (Fuel Can Filter)
Install a filter to the outlet tube of your
refueling container to prevent entry of
foreign matter into fuel tank. O.S. ‘Super
Filters’ (large and small) are available as
optional extras.
Fuel Filter
It is recommended to install a good in-
line filter between the fuel tank and
carburetor to prevent entry of foreign
matter from getting into the carburetor.
Silicone Fuel Line
Heatproof silicone tubing of approx.
5-5.5mm o.d. and 2.5mm i.d. is
required for the connection between
the fuel tank and engine.
Manual
D
Electric
P
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.
8mm as
End Wrenches
8mm, 13mm, 14mm, etc.
Needle Nose Pliers

OS arene
The under-surfaces of all O.S. engine beam
mounting lugs are precision machined flat and
exactyly parallel to the engine's horizontal axis. It is
essential that the engine mounts in the model are
also accurately made and aligned. If they are not,
they will cause stress and distortion within the engine
itself, probably resulting in loss of performance and
internal damage.
The recommended screws for securing the engine to
the engine mounts in the model are 4mm or 4-40
steel Allen type. It is also advisable to use lock
washers or LOCTITE to prevent nuts from loosening.
OS arene
E Installing The Glowplug
Z
Install washer on glowplug
and insert carefully into
Heatsink-head, making sure
that it is not cross-threaded
before tightening firmly.
`
Glow plug
Washer —©
16
17
INSTALLATION OF THE ENGINE
( CORRECT
o GF)
Front view Side view
Top surfaces are in the same plane.
INCORRECT
x a
14
=
Top surfaces are not Top surfaces are not in the
in the same plane. same plane.
pA Engine does not rest firmly.
Re-align the surfaces as necessary
Make sure that only the under-
surfaces of the engine’s mounting
lugs are in contact with the engine
w mount.
INSTALLATION OF THE STANDARD ACCESSORIES
E Installation of Velocity Stack
Install the velocity stack supplied on the carburetor
with M3x3 set-screw supplied.
Cut outthe cooling fan duct so that velocity stack man
not interfere the duct.
The velocity stack develops its performance when
it is completely located inside the duct.
About The Head Gasket
The engine is installed with a 0.2mm thick head
gasket at the factory. When a 15% nitro fuel is used,
run the engine as itis. When a 23% or 30% nitro fuel
is used, add 0.1mm or 0.2mm thick gasket for easier
tuning.

OS avez
E INSTALLATION OF THE CARBURETOR
As delivered, the engine has its carburetor lightly
fitted into its intake boss. Secure it as follows.
1. Loosen carburetor retainer screw slightly.
2. Insert the carburetor rubber
gasket on the carburetor
body securely.
Then, insert the carburetor
in the crankcase.
Carburetor Rubber
Gasket
OS avenue
CARE OF REGURETOR
E NEVER disassemble the pressure regulator.
Their original performance may not be restored
after reassembly.
E NEVER insert anything into the inlet nipple in an
attempt to clear a suspected obstruction.
EDO NOT block the five holes on the top of the
regulator, or the regulator may not work properly.
Do not insert a needle or anything into these holes.
EDO NOT allow foreign matter to enter the fuel
system. Dirt inside the regulator, no matter how
small, may obstruct the flow of fuel and prevent a
from working properly.
a
19
Note: In case it is hard to insert the carburetor in
the crankcase, apply oil on the Thermo Insulater.
Do not force it, or damage to the Thermo Insulater
and/or crankcase can occur.
3. Rotate the retainer screw gently until it stops, then
tighten a further 90-120 degrees.
Do not over-tighten the screw as this will damage
the Thermo Insulater.
Carburetor Rubber
Gasket
Retainer screw
0.2mm gap
Ne A
ABOUT THE REGURETOR
E ALWAYS use fuel filters.
Keep the fuel tank scrupulously clean and filter all
fuel as it enters the tank (e.g.via an O.S.'Super-
Filter’ Code No.72403050) and use a good quality
in-line filter between the tank and regulator.
Remember to inspect filter screens at regular
intervals and rinse clean as necessary.
m DO NOT clean the regulator with organic solvent
such as kerosene, light machine oil, gasoline,
thinner or cre as the silicone rubber parts inside
will deteriorate. Be sure to use methanol or fuel.
E DO NOT allow fuel to remain in the regulator.
After finishing the day's flight session, be sure to run
out the fuel in the regulator. Stop the fuel flow to the
regulator with a stopper and run the engine at idle to
use up the fuel in the regulator. After stopping the
engine, rotate the engine by electric starter to
eliminate fuel inside the engine.