O.S. engine MAX FXi 46 Setup guide

© Copyright 2003 HCAZ3085
MAX FXi 46
OWNER’S INSTRUCTION MANUAL
It is of vital importance, before attempting to
operate your engine, to read the general
“SAFETY INSTRUCTIONS AND WARNINGS”
section on pages 2-6 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 aircraft, radio control
equipment, etc., are accessible for checking
at the same time.

SAFETY INSTRUCTIONS AND WARNINGS
ABOUT YOUR O.S. ENGINE ................................3
FEATURES OF FXi SERIES ENGINE ..................7
BEFORE INSTALLING THE ENGINE....................7
BASIC ENGINE PARTS ........................................8
INSTALLATION OF THE ENGINE ........................8
THROTTLE LINKAGE............................................8
MUFFLER..............................................................9
FUEL TANK LOCATION ........................................9
GLOW PLUG ......................................................10
FUEL....................................................................11
PROPELLERS ....................................................12
MIXTURE CONTROLS........................................12
BEFORE STARTING............................................13
STARTING ..........................................................14
RUNNING-IN (Breaking-in)..................................15
NEEDLE VALVE ADJUSTMENT DIAGRAM........17
MIXTURE CONTROL VALVE ADJUSTMENT ....19
REALIGNMENT OF MIXTURE CONTROLVALVE ..19
SUBSEQUENT STARTING PROCEDURE..........20
SUBSEQUENT READJUSTMENT......................20
CARBURETOR CLEANLINESS..........................21
ENGINE CARE & MAINTENANCE ....................22
O. S. ENGINES LIMITED WARRANTY ..............22
ENGINE EXPLODED VIEW ................................24
ENGINE PARTS LIST..........................................25
CARBURETOR EXPLODED VIEW ....................26
CARBURETOR PARTS LIST ..............................26
CONTENTS
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.
The advice which follows is grouped under
two headings according to the degree of
damage or danger which might arise
through misuse or neglect.
NOTES!
These cover the many other possibilities,
generally less obvious sources of danger,
but which, under certain circumstances,
may also cause damage or injury.
WARNINGS!
These cover events which might involve
serious (in extreme circumstances, even
fatal) injury.
SAFETY INSTRUCTIONS AND
WARNINGS ABOUTYOUR O.S. ENGINE
3

NOTES!
• This engine was designed for model
aircraft. 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.
• Be sure to use the muffler supplied with
the engine. Frequent exposure to an
open exhaust may eventually impair
• Never operate your engine in an
enclosed 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.
WARNINGS!
• Never touch, or allow any object to
come into contact with, the rotating
propeller and do not crouch over the
engine when it is running.
• A weakened or loose propeller may
disintegrate or be thrown off and, since
propeller tip speeds with powerful
engines
may exceed 600 feet (180 meters)
per
second, it will be understood that
such a failure
could result in serious
injury, (see
“NOTES!” section relating to
propeller safety).
• 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 fuel.
4

• If you fit a spinner, make sure that it is a
precision made product and that the
slots for the propeller blades do not cut
into the blade roots and weaken them.
• Preferably, use an electric starter. The
wearing of safety glasses is also
strongly recommended.
• Discard any propeller which has
become split, cracked, nicked or
otherwise rendered unsafe. Never
attempt to repair such a propeller,
destroy it. Do not modify a propeller in
any way, unless you are highly
experienced in tuning propellers for
specialized competition work such as
pylon racing.
• Take care that the glow plug clip or battery
leads do not come into contact with the
propeller. Also check the linkage to the
throttle arm.A disconnected linkage could
also foul the propeller.
your hearing.Such noise is also likely to
cause annoyance to others over a
wide area.
• If you remove the glow plug from the
engine and check its condition by
connecting the battery leads to it, do not
hold the plug with bare fingers. Use an
appropriate tool or a folded piece of cloth.
• Install a top-quality propeller of the
diameter and pitch specified for the
engine and aircraft. Locate the propeller
on the shaft so that the curved face of the
blades face forward–i.e.in the direction of
flight. Firmly tighten the propeller nut,
using the correct size wrench.
• Always check the tightness of the
propeller nut and retighten it, if
necessary, before restarting the engine,
particularly in the case of four-stroke
engines. If a safety locknut assembly is
provided with your engine, always use
it. This will prevent the propeller from
flying off in the event of a "backfire",
even if it loosens.
5

Do not start your engine in an area
containing loose gravel or sand. The
propeller may throw such material in
your face and eyes and cause injury.
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. Keep the propeller
pointed away from you and walk well
clear of spectators.
•Warning! Immediately after a glow plug
ignition engine has been run and is still
warm, conditions sometimes exist
whereby it is just possible for the engine
to abruptly restart if the propeller is
casually flipped over compression
WITHOUT the glow plug battery being
reconnected. Remember this if you
wish to avoid the risk of a painfully
rapped knuckle!
NOTES!
• 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.
• Take care that loose clothing (ties, shirt
sleeves, scarves, etc.) do not come into
contact with the propeller. Do not carry
loose objects (such as pencils,
screwdrivers, etc.) in a shirt pocket from
where they could fall through the
propeller arc.
• After starting the engine, carry out any
needle-valve readjustments from a safe
position behind the rotating propeller.
Stop the engine before attempting to
make other adjustments to the
carburetor.
6

This range of engines is ideally suited to a
variety of R/C aircraft, including trainer,
sports, acrobatic and scale types.
A separate precision-made needle-valve
unit is installed at the rear, where manual
adjustment is safely remote from the
rotating propeller.
Common Accessories
No. 8 Glow Plug, Silicone Tube, Instruction
Manual.
Note: With these engines, the piston will
feel tight at the top of its stroke when the
engine is cold. This is normal.The piston
and cylinder are designed to achieve a
perfect running clearance when they
reach their intended running temperature.
Installing the Glow Plug
Carefully insert plug, with washer, finger
tight only, before final tightening with the
correct size plug wrench.
Connecting the Fuel Tubing
Connect the short length of fuel tubing
(supplied) securely between the needle-
valve outlet and carburetor inlet as shown in
the illustration on the next page.
In the event of the tubing becoming
damaged, it should be replaced with a
suitable length (as indicated below) of best
quality 5mm OD x 2mm ID silicone tubing.
Use similar material to connect the fuel inlet
nipple to the fuel tank.
BEFORE INSTALLING THE ENGINE
FEATURES OF FXi SERIES ENGINE
7

Installation in the Model
Make sure that the mounting beams are
parallel and that their top surfaces are in the
same plane.
• Before connecting the throttle-
lever/servo linkage, make sure that no
part of the linkage interferes with the
internal structure of the aircraft or
wiring, etc., when the throttle is fully
open or fully closed.
• Set the throttle lever linkage so that the
throttle rotor is (a) fully open when the
transmitter throttle stick is fully
advanced and (b) fully closed when the
THROTTLE LINKAGE
INSTALLATION OF THE ENGINEBASIC ENGINE PARTS
8

throttle stick is fully retarded.
Adjustment of the throttle rotor opening
at the idling position can then be made
with the throttle trim lever on the
transmitter. (Select throttle-lever and
servo-horn hole positions that will
avoid excessive pushrod travel causing
the throttle to bind at either end.)
Note: When adjusting the throttle lever
angle, relative to the rotor, hold the rotor
at about half-way between the open and
closed positions while loosening and
tightening the fixing screw, otherwise
the rotor, rotor guide screw, throttle stop
screw or carburetor body may become
burred and damaged.
The exhaust outlet of the silencer can be
rotated to any desired position in the
following manner:
1) Loosen the locknut and assembly screw.
2) Set the exhaust outlet at the required
position by rotating the rear part of
the silencer.
3) Re-tighten the assembly screw,
followed by the locknut.
Note: The standard expansion-chamber
type silencer is quite effective, but
reduces power to some degree.
Reminder: 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.
Keep your hands and face away from
exhaust gas or you will suffer a burn.
Suggested fuel tank capacities are listed
opposite.These will allow 12-13 minute flights.
Locate the fuel tank so that the top of the
FUEL TANK LOCATION
MUFFLER
9

tank is 5-10mm (1/4-3/8") above the level of
the needle valve.
Be sure to use a pressurized fuel system by
connecting the muffler pressure nipple to
the vent pipe of the fuel tank.
Since the glow plug and fuel combination used
may have a marked effect on performance and
reliability, it would be worthwhile to experiment
with different plug types.
Recommended O.S. plugs are Nos. 8, A5
and A3. Carefully install plug finger-tight,
before final tightening with the correct size
plug wrench.
The Role of the Glow Plug
With a glow plug 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 becomes cooler and
ignition is retarded.
Glow Plug Life
Particularly in the case of very high
performance engines, glow plugs must be
regarded as expendable. 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 nitro methane 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.
GLOW PLUG
10