O.S. engine MAX-46FX-Hring 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 model, radio control equipment, etc.,
are accessible for checking at the same time.
●
●

CONTENTS
SAFETY INSTRUCTIONSAND WARNINGS
ABOUT YOUR O.S. ENGINE
INTRODUCTION,
BASIC ENGINE PARTS
INSTALLATION
INSTALLATION OF COOLING FAN,
BEFORE STARTING
FACTS ABOUT GLOW PLUGS,
FUEL
CARBURETOR CONTROLS
STARTING
RUNNING-IN
ADJUSTMENT
SUBSEQUENT READJUSTMENTS
CARBURETTOR CLEANLINESS
ADJUSTING CHART
INSTALLATION OF THROTTLE SERVO
CARE AND MAINTENANCE
ENGINE EXPLODED VIEW &
PARTS LIST
CARBURETOR EXPLODED
VIEW & PARTS LIST
THREE VIEW DRAWING
O.S. GENUINE PARTS & ACCESSORIES
2 ~ 5
6
7
8 ~ 10
10
~ 11
12
13 ~ 14
18
21
22
~ 25
26
27
14
19
28
15 ~ 17
20
1

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 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.
2

WARNINGS
••
•
•
•
Never touch, or allow any
object to come into contact
with, the rotating parts.
Model engine fuel is poison-
ous. 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,oranythingelsewhich
might ignite it. Do not smoke
orallowanyoneelsetosmoke,
near to it.
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.
Never operate your engine in an en-
closed space. Model engines, like auto-
mobile engines, exhaust deadly carbon-
monoxide. Run your engine only in an
open area.
3

NOTES
•
•
•
•
•
These engine were designed for model
helicopters. Do not attempt to use it for any
other purpose.
Mount the engine in your model securely, fol-
lowing 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 high-speed
engines) may eventually impair your hearing
and such noise is also likely to cause
annoyance to others over a wide area.
Check the linkage to the throttle arm before
each flight.
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.
•
•
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.
Use an electric starter. The wearing of safety
glasses is also strongly recommended.
Press the rotor head down securely.
Take care that the glow plug clip or battery
leads do not come into contact with rotating
parts.
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.
•
•
4

NOTES
•
•
•
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
metres) 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! lmmediately 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.
5

Because of initial tightness, 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, however,
confuse tightness with the symptoms of
hydraulic lock caused by an excess of fuel
within the cylinder - often the result of over-
priming. Attempting to force the engine to
turn over in this condition may cause
internal damage. Instead, remove the
glowplug, invert the engine and eject
surplus fuel from the combustion-chamber.
Note:
The MAX-46FX-H RING is a high-
performance engine that has been
developed expressly for "medium-sized"
radio-controlled helicopters.
INTRODUCTION BASIC ENGINE PARTS
Heatsink Head
Carburettor
Typr 40E
Crankshaft
Propeller nut
Crankcase
Drive Hub
Glowplug
Beam Mount
Cover Plate
MAX-46FX-H RING
6

INSTALLING THE GLOWPLUG
Install the washer on the
glowplug and screw
carefully into cylinder-
head, making sure that it
is not cross-threaded
before tightening firmly. Glow plug
Washer
INSTALLATION OF THE ENGINE
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 3mm or 4-40
steel Allen type. It is also advisable to use lock
washers or LOCTITE to prevent nuts from loosening.
Front view
CORRECT
Side view
Top surfaces are in the same plane.
Re-align the surfaces as necessary
INCORRECT
Top surfaces are not
in the same plane. Top surfaces are not in the
same plane.
Engine does not rest firmly.
Make sure that only the under-surfaces
of the engine’s mounting lugs are in
contact with the engine mount.
If the crankcase body touches the
mount, chamfer the edges of the mount.
7

BEFORE STARTING
Tools, accessories, etc.
The following items are necessary for operating the
engine.
1 Fuel
Model glowplug engine fuel of good quality, preferably
containing a small percentage of nitromethane.
INSTALLATION OF COOLING FAN
As supplied the MAX-46FX-H is equipped with a
conventional drive hub, keyed to flats on each side of
the crankshaft. However, some helicopters require
this to be replaced by a taper collet for cooling fan
installation. Fit this as follows. Rotate crankshaft to
TDC. Remove drive hub and thrust washer. Slide
taper collet onto 3/8-in. dia. front journal with its slot
uppermost-i.e.along the full diameter of the journal
NOT passing over the gap formed either side of the
flats. It is not necessary to replace the thrust washer.
Open slot in taper collet
Flats each side of
crankshaft front journal
for drive hub.
Front Journal
Split Taper Collet
3 Glowplug battery
The power source for heating the glowplug may be
either a large heavy-duty 1.5volt dry cell, or preferably,
a 2-volt rechargeable lead-acid cell .
1.5 volt heavy-duty
dry battery or 2 volt rechargeable lead-acid cell (at least 5Ah)
If a 2-volt cell is employed,
use a resistance wire, as
shown, to reduce applied
voltage, otherwise element
will overheat and burn out.
2 Glowplug
O.S. No.8 glowplug is installed in the engine.
8

Resistance coil
(nichrome wire)
Adjust applied voltage by changing the position of clip on
resistance coil until glowplug element is glowing bright red.
Battery leads
Raise
voltage to
increase
brightness.
Lower voltage to
reduce brightness.
Warning (Very hot)
Never touch the
nichrome wire
while the battery
is connected.
4 Plug wrench
Used for tightening glowplug. The
O.S. long plug wrench is available
as an optional accessory.
5 Battery leads
These are used to conduct current
from the battery to the glowplug.
Basically, two leads, with clips, are
required, but, for greater conve-
nience, twin leads with special
glowplug connectors, as shown on
theright,arecommerciallyavailable.
6 Fuel bottle or pump
For filling the fuel tank, a simple,
polyethylene"squeeze"bottle,with
a suitable spout,is all that is
required. Alternatively, one of the
purpose-made manual or electric
fuelpumpsmaybeusedto transfer
fuel directly from your fuel
container to the fuel tank.
For tightening
glowplug
Fuel bulb
Battery leads
Manual Electric
Fuel pumps
Fuel Can Filter
7 Fuel container filter
Install a filter on the outlet tube
of your refuelling container to
prevent entry of foreign matter
into the fuel tank
8 Silicone tubing
This is required for the
connection between the fuel
tank and engine.
Silicone tube
9

FACTS ABOUT GLOWPLUGS
The role of the glowplug
Glowplug life
Particularly in the case of very high performance
engines,
glowplugs must be regarded as expendable
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.
Since the compatibility of 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 No.8, A5 and A3. Carefully install plug finger-tight,
before final tightening with the correct size plug
wrench.
12V Battery Starter
10 Electric starter and starter
battery
An electric starter is recom-
mended for starting.
9 Hexagon starting shaft
This shaft mounted on an
electric starting motor is driven
into the main body of a
helicopter to turn the engine.
10

Install a plug suitable for the engine.
Use fuel containing a moderate percentage of
nitromethane.
Do not run the engine too lean and do not leave the
battery connected while adjusting the needle.
However, plug life can be extended and engine
performance maintained by careful use, i.e.:
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.
•
•
•
•
•
•
•
•
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.
Modelenginefuelispoisonous.Donotallow
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
whichmightigniteit.Do not smoke,orallow
anyone else to smoke, near to it.
Reminder!
11

CARBURETOR CONTROLS
With a fixed-wing model, power failure is rarely a
serious threat to the safety of the aircraft since it can
usually glide down to a safe landing. In a helicopter,
on the other hand, it is vitally imporant that the engine
keeps running and that there is a quick and reliable
response to the throttle in order to ensure safe ascent
and descent of the model.
The Needle Valve:
When set to produce maximum power at full throttle,
this establishes the basic fuel/air mixture strength.
This is then maintained by the carburetor's
automatic mixture control system to cover the
engine's requirements at reduced throttle settings.
The Mixture Control Valve (Mixture ControlScrew):
For adjusting the mixture strength at part-throttle
and idling speeds, to obtain steady idling and
smooth acceleration to medium speeds. The Mixture
Control Valve has been factory set for the
approximate best result. First, run the engine as
received, and re-adjust the Mixture Control Valve
only when necessary.
Two adjustable controls are provided on this carburetor.
Needle Valve Throttle Lever
Mixture Control Valve
(MIxture Control Screw)
•
•
RE-ESTABLISHMENT OF MIXTURE CONTROL
VALVE SETTING
In the course of making carburetor adjustments, it is
just possible that the Mixture Control Valve may be
inadvertently screwed in or out too far and thereby
moved beyond its effective adjustment range.
Its factory setting can be reestablished as follows;
Disconnect the throttle linkage by removing the
control rod from the throttle lever.
Fully close the throttle.
Turn the Mixture Control Valve clockwise gently
until it stops, while keeping the throttle fully closed.
Do not over-tighten the valve.
Turn the Mixture Control Valve 2-1/2 turns counter-
clockwise from the above position. This is the
basic (factory) setting.
1.
2.
3.
4.
12

STARTING
Close
Open
Be sure to use a muffler pressurized fuel feed. Use
the same fuel as you intend to employ for actual
operation of your model.
1.
2.
3.
Opening and closing of the Needle-Valve
Turn the needle clockwise to
close the needle-valve, and turn
the needle counter-clockwise to
open the needle-valve as shown
in the sketch.
Opening the needle-valve
Firstly, turn the needle clockwise slowly until it
stops. The position it stops is the fully closed
position of the needle-valve. Make note this
position for reference..
Open the needle-valve 2 turns.
Preparation of the starter
Install the starting shaft to the
starter securely. Poor installation
swings the starting shaft, which is
dangerous.
4.
5.
6.
Checking the rotating direction of the starter
Make sure that the starter rotates
to the direction shown in the
sketch. If the direction is reverse,
reverse the leads on battery.
Inserting the starter shaft
Insert the starting shaft into the
shaft cup securely.
Priming
Without heating the glowplug, open
the throttle a little from the idling
position. Turn the engine using the
starter until the fuel is seen to reach
carburetor.
Preparation of starting
Make sure that the transmitter
throttle stick is at the fully closed
position and the throttle trim at
center position, and make sure that
idle-up switch on the transmitter is
off. Hold the rotor head by hand so
that rotor cannot rotate when the
engine is Started. Also, steady the
model with a foot on the landing-
gear skid.
7.
13

In case the engine does not stop.
Hold the rotor head, and pinch the silicone tube to
stop the fuel supply. If it still does not stop, pull off the
fuel tubing from the carburetor. It is necessary to
readjust the throttle linkage so that the carburetor
rotor is fully closed when the throttle stick and throttle
trim on the transmitter are fully pulled Down.
Stopping the engine
Fully pull down the throttle trim on the transmitter.
Starting
Connect the battery to the glowplug and start the
engine by applying the starter. When started,
switch off the starter and withdraw the starting
shaft after making sure the rotation of the starter
shaft stops.
8.
9.
NOTE:
If the throttle response is poor or the engine
stops due to a temporarily over-rich mixture im-
mediately after the engine is started, pinch the
fuel line for one or two seconds until the engine
r.p.m. increase and the engine runs steadily.
Reminder!
Never touch, or allow any object to
come into contact with, the rotating ro-
tor.
All internal-combustion engines benefit, to some
degree, from extra care when they are run for the first
few times known as running-in or breaking-in.
This is allows the working parts to mate together
under load at operating temperature.
However, because O.S. engines are made with the
aid of the finest modern precision machinely and from
the best and most suitable materrials, only a very
short and simple running-in procedure is required and
can be carried out with the engine installed in the
model. For the first few flights with a new engine i.e.
while the engine is being run-in set the needle-
valve for a slightly rich mixture not excessively rich
as this may result in poor throttle response and cause
the engine to stope. About one-quarter turn open
from the nomal setting will usually suffice.
RUNNING-IN ("Breaking-in")
14

A
ADJUSTMENT
The following adjustments are approximately correct
when using a fuel containing 25% lubricant and 10-
30% nitromethane. Bear in mind that fuels containing
relatively large percentages of power-boosting
nitromethane operate at richer mixture settings than
are needed for mild fuels and will, therefore, require
the Needle Valve to be readjusted accordingly. The
type and percentage of lubricant used is also a factor
here, as noted later in these instructions.
This carburetor is not fitted with a throttle
stop screw. Instead, idling speed is adjus-
ted by means of the throttle trim lever on
the transmitter. This enables the full r.p.m.
range, from idling to full power, to be control-
led by the throttle stick, and then allows the
engine to be stopped, from the transmitter, by
closing the throttle completely with the trim
lever.
Set up the throttle linkage as follows:
With the transmitter throttle trim lever fully
retarded, adjust the throttle servo linkage so that
the throttle rotor is (a) fully open when the
transmitter throttle stick is fully advanced and (b)
fully
closed (i.e. engine stopped) when the stick is
fully
retarded.The idling speed is then set by
advancing the throttle trim lever to the point
where the engine runs, steadily and reliably,at the
desired idling speed.
As a safety measure, first check the transmitter
controls, including the throttle stick and trim lever
positions, and hold the main rotor securely before
starting the engine.
Warm the engine by allowing it to idle for about 30
seconds. If the engine stops, advance the throttle
trim lever slightly to increase the idling rpm. Then
open the throttle sufficiently to 'float' the model
above the ground.
B
C
Open the Needle Valve 2 turns from the fully
closed position.(Be sure to use a muffler-
pressurized fuel feed.)
NOTE:
15

lf, at this time, the engine is slow to pick up and
produces an excess of exhaust smoke, the mixture
is too rich. Correct this condition by turning the
Mixture Control Screw clockwise. lf the mixture is
extremely rich, engine rpm will become unstable :
opening the throttle will produce a great deal of
smoke and rpm may drop suddenly or the engine
may stop. This condition may also be initiated by
an excessively prolonged warming-up period.
lf, on the other hand, the mixture is too Iean, this
wiIl be indicated by a marked lack of exhaust
smoke and a tendency for the engine to cut out
when the throttle is opened. ln this case, turn the
Mixture Control Screw counter-clockwise to enrich
the mixture.
Turn the Mixture Control Screw 30 degrees at a
time.
Having provisionally set the idle mixture, the next
step is to adjust the mixture for hovering flight.
D
E
F
G
Hover the model and actuate the throttle to
observe response over the medium speed range.
lf the engine smokes excessiveIy and throttle
response is poor, the mixture is too rich ; in which
case, land the model and turn the Needle Valve
clockwise. Do not close the NeedIe Valve too
much, keeping it a little on the rich side at this
stage.
lf, on the other hand, hovering is not stable and
response to the throttIe is over-sensitive, or if the
engine tends to overheat, this indicates that the
mixture is too lean and should be corrected by
turning the Needle Valve counter-clockwise.
When satisfactory hovering flight has been
achieved, land the modeI again and re-check the
engine's idlling qualities.
After about 10 seconds of idling, open the throttle
to 'float' the model. lf the transition is smooth, the
idle mixture is O.K. If the symptoms of either rich
or Iean running are
observed, readjust the Mixture
Control Screw accordingly.
Now adjust the Needle Valve to achieve the best
performance when the model is flying at full
throttle. lf, at full throttle, acceleration is poor, the
H
I
J
K
L
16

exhaust unduly smoky and the model fails to reach
expected straight line speed, the mixture is too rich
and the Needle Valve setting will need to be
reduced. lf, however, after smoothly acceIerating
to satisfactory high-speed straight and level flight,
power is lost when the model is puIled up into a
climb, the mixture is too lean. ln this case, land the
model immediately and readjust Needle Valve to a
richer setting.
Now re-check hovering performance and, if
necessary, fine-tune the mixture for hovering flight.
For helicopters, good throttle response at medium
r.p.m. (e.g.hovering speeds) is most important,
since this is a power range widely used in
helicopter flight. The optimum fuel/air mixture
strength at medium speeds is dependent on
obtaining balanced adjustment of both the Needle
Valve and the Mixture Controlof both the Needle
Valve and the Mixture Control Valve. lf both
controls are already at their optimum setting, some
modification to these settings may be necessary to
achieve satisfactory mid-range throttle response,
but such readjustments should onIy be made
within the range where idling reliability and high-
speed performance are not unduly compromised.
M
N
O
Readjustments should therefore be carried out as
follows:
lf the mid-range throttle response is not rapid and
positive (indicating a rich mid-range mixture), turn
the Needle Valve 2 or 3 clicks clockwise, or turn the
Mixture Control Screw 10-20 degrees cIockwise.
lf, on the other hand, the response to mid-range
throttle movement is too sensitive (indicating a lean
mid-range mixture), turn the Needle Valve 2 or 3
clicks counter-clockwise or turn the Mixture Control
Screw 10-20 degrees counter-clockwise.
Throttle response at hovering speeds is aIso
affected by the reIationship of the main rotor pitch
angle to throttle opening. If the optimum mid-range
throttle response cannot be obtained by the
carburetor adjustments described above, try
adjusting the helicopter's pitch control
characteristics.
Q
P
17

SUBSEQUENT READJUSTMENTS
Once the engine has been run-in and the carburetor
controls properly set up, it should be unnecessary to
alter the mixture settings, except to make minor
adjustments to the Needle Valve occasionally, to take
account of variations in climatic condisitions.
The use of a different fuel, however, particularly one
containing more, or less, nitromethane and / or a
different type or proportion of lubricating oil, is likely to
call for some readjustment of the Needle-Valve.
Remember that, as a safety measure, it is advisable
to increase the Needle Valve opening by an extra
half-turn counter-clockwise, prior to establishing a
new setting. The same applies if the silencer type is
changed. A different silencer may alter the exhaust
pressure applied to the fuel feed and call for a revised
Needle-Valve setting.
The use of a different glowplug, or changes to the
mainrotor and its pitch angles may also require
compensating carburetor readjustments.
CARBURETOR CLEANLINESS
The correct functioning of the carburetor depends on
its small fuel orifices remaining clear.
The minute particles of foreign matter that are present
in any fuel can easily partially obstruct these orifices
and upset mixture strength so that engine
performance becomes erratic and unreliable.
It is recommended that fuel is passed through a filter
when the tank is filled and that a good in-line filter is
installed between the fuel tank and carburettor and,
furthermore, that this filter is frequently cleaned to
remove dirt and lint that accumulates on the filter
screen.
Finally, occasionally remove the needle-valve holder
from the carburetor as shown in Photo and extract
any remaining foreign matter that may have lodged in
the location shown in Photo, right.
Remove this with
an 8mm spanner Dirt and fbrous matter
mostly accumulate here
18

ADJUSTING CHART
Open the Needle Valve 2 turns from the fully closed position.
Make sure that the Mixture Control Valve is at the factory setting.
A
Start the engine
Warm up the engine
B
C
Observe the mixture condition while "floating" the model
Turn the Mixture
Control Screw
counter-clockwise Idling OK
Turn the Mixture
Control Screw
clockwise
Lean mixture Rich mixture
DE
F
E
Observe the hovering mixture condition
Open the
Needle Valve
(Turn counter-clockwise)
Hovering OK
Lean mixture Rich mixture
J
H
I
G
Close the
Needle Valve
(Turn clockwise)
Land the model
Idle for approx: 10 seconds, then reopen throttle to
observe transition ("Float" the model)
Turn the Mixture
Control Screw
counter-clockwise Idling OK
Turn the Mixture
Control Screw
clockwise
Lean mixture Rich mixture
High Speed Flight
Open the
Needle Valve
(Turn counter-clockwise)
Lean mixture Rich mixture
L
M
Close the
Needle Valve
(Turn clockwise)
High Speed Flight OK
Fine tuning of hovering mixture
Turn the Needle Valve
2 or 3 clicks counter-
clockwise, or turn the
Mixture Control Screw
10-20 degrees counter-
clockwise. Adjust pitch
control characteristics.
Hovering OK
Response too sensitive
N
Response too slow
Adjustment completed
PQOQ
Turn the Needle Valve
2 or 3 clicks clockwise,
or turn the Mixture
Control Screw 10-20
degrees clockwise.
Adjust pitch control
characteristics.
K
19