Corsair BLACK BULL User manual

BLACK BULL
USER’S MANUAL
Last update September 2020
ENGINE CONFIGURATIONS AVAILABLE
ELECTRIC STARTER
HAND STARTER
HYBRID

Black Bull Manual
1
INDEX
I DENTIFICATION OF THE OWNER AND
INTRODUCTION
2
TECHNICAL AND STRUCTURAL
FEATURES
3
M AIN TORQUES 5
ASSEMBLEY 6
A DJUSTMENT CARBURETOR /
RUNNING IN
7-8
M AINTENANCE
T ENSION OF REDUCTION BELT 11
W ARRANTY 13
T ROUBLE SHOOTING 14
I MPORTANT ADVICE 15
N OTES 1

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2
IDENTIFICATION OF THE OWNER
Owner
Address
Serial number
Reseller
Address
Owner’s signature
Reseller’s signature and stamp
Date of sale
Introduction:
Thank you for choosing our engine BLACK BULL CORS-AIR ENGINE.
We tried to do everything possible to give accurate and update technical
information in this manual.
The Company riserve the right to make technical and aesthetic changes without notice in
order to improve quality of product.
The information written here is the exclusive property of CORS-AIR.
So they are not allowed reproduction or replication in whole or part without the express
permission of the CORS-AIR.
This manual has been prepared to provide technical information necessary for the
installation and repair of motors.
We invite you to spend some time reading this to avoid risks to the health and safety of
people and economic damage.
Furthermore, we invite you to deliver this manual together with the engine if you sell it, so it
can be useful for the next owner as well.
The manufacturer and the resellers are ready to answer your questions and, if
necessary, to solve every problem, because YOUR AND THE OTHER PEOPLE’S
SAFETY IS THE MOST IMPORTANT THING FOR US.

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CYCLE
T WO STROKE
TOTAL DISPLACEMENT
235 C . C .
BORE
70mm
STROKE
61mm
COMPRESSION RATIO
10.5:1
COOLING
B Y AIR
PEAK RPM max.
8000 /8300 RPM
PISTON
W ITH TWO PISTON RINGS
EAD
I N ALLOY WITH HIGH PERCENTAGE OF SILICONAN
HEMISPHERIC COMBUSTION CHAMBER , WITH SQUISH
CRANKCASE
M OLTEN IN G-A L S I UNI 3051 ALLOY
SUBSEQUENTLY TREATED AND ANODIZED AGAINST
SEA SALT
CONNECTING ROD
I N COPPER PLATED STELL 18 N I C R M O 5 JOINED TO
THE DRIVE SHAFT THROUGH VERY PRECISE HIGH
SPEED SILVER - PLATED ROLLER BEARINGS
CARBURATOR
DIAPHRAGM
FEEDING
S IX BLADE REED - VALVE SYSTEM CONNECTED TO THE
CRANKCASE
SPARK PLUG
N GK BR 8 ES OR SIMILAR
SYSTEM
S IX PORT DISTRIBUATION AND EXHAUST WITH
BOOSTER
CYLINDER
I N ALLOY WITH NIKASIL COATING
REDUCTION
W ITH POLY V BELT AVAIBLE IN 1:3.0
CYLINDER EAD
TEMPERATURE
MAX TEMPERATURE 230°C MEASURED UNDER SPARK
PLUG
E XHAUST GAS TEMPERATURE NOT EXCEEDING 5 0 C°
ENGINE MOUNTING
B Y 4 SHOCK ABSORBING RUBBER MOUNTS
ROTATION
C OUNTERCLOCKWISE
DRIVE S AFT
I N 18 N I C R M O 5 WITH 5 THERMIC TREATMENTS ON
EVERY COMPONENT
SEAL RING
I N V ITON WITH VERY HIGH RESI STANCE AND LONG
DURATION
FUEL
M IXTURE 2,2% / 2.5% WITH SYNTHETIC OIL ,
SUGGESTED BRANDS : M ALOSSI 7.1—W LADOIL

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K2T—E LF 2T M OTO
OIL
2.2% - 2,5%
ENGINE WEIG T
H AND START KG 16,7 COMPLETE WITH 2018 VERS .
EXHAUST AND INCLUDING RUBBER MOUNTS AND
AIRBOX IN CARBON
E LECTRIC START KG . 17,4 COMPLETE WITH 2018
VERSION EXHAUST , INCLUDING RUBBER MOUNTS AND
AIRBOX IN CARBON

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MAIN TORQUES
IMPORTANT:
Remember that the battery of the electric start should be recharged
before starting the engine.
MAIN TORQUES
Kg. m
(Nm)
N UTS TO FIX THE HEAD 2,5 25
N UTS TO FIX HALF - CRANKCASE 1,2 12
N UTS TO FIX THE PINION ( SMALL PULLEY ) 3,5 35
N UTS TO FIX IGNITION HANDWHEEL (manual
version)
4,5 45
N UTS TO FIX IGNITION HANDWHEEL (electric
version)
2,5 25
G AP BETWEEN COIL AND HANDWHEEL MIN . 0,3 mm
MAX . 0,4 mm
T IGHTENING OF REED VALVES PLATE 1,2 12
P ISTON RINGS GAP TOLLERANCE 0,25 mm

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ASSEMBLY:
You can install the engine on the frame by using 4 rubber mounts of 40 x 30
mm between the back flange and the engine mount.
To attach the propeller use only bolts of class 10.8 (100 Kg) and make sure
that their length is enough to exit from the reductor-pulley. Tighten the 6 bolts
M8 in a cross, at 1.5 Kg.m.(15Nm). Re-check the torque of the bolts after the
first hour of engine’s working.
We suggest not touse a variable pitch carbon prop, because the big hub
pushes the prop too forward, with possible damages to pulley and bearings.
For the connection between the carburetor and the fuel tank use a proper
hose of the right diameter.
The length of the fuel line should not be longer than 80 cm.
It is advisable to install a manual primer bulb to get the fuel to the carburetor
before for starting. This device will allow the fuel to arrive to the carburettor,
protecting in this way the battery.
IMPORTANT NOTES
DO NOT try to start the engine without the propeller.
DO NOT start the engine with loose bolts or parts, since this can cause the
detaching of the propeller, the ovalization of the propeller holes, the damage
of the electric start and the breakage of the rubber mounts.
BATTERY must be loaded and use a 6 Ah battery.
IMPORTANT! BEFORE FLYING C ECK ALWAYS EVERY PART OF
YOUR CRAFT, FROM ENGINE TO FRAME.
Verify that there are no damaged electric wires, that there are no leaks from
hoses, tank, carburettor or engine’s crankcase, that the propeller is not
damaged or loose, that the exhaust-pipe has no cracks, that the frame is not
bent or broken because of falls, that rubber mounts are not cracked, that the
reduction belt is not loose and every bolt is tight.
Finally you can start the engine, leaving it to warm up at a speed of 3000 to
4000 rpm with head temperature at least 0/100 °C, before start taking off so
to avoid piston seizing.

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FUEL
Use for the mixture only premium gas for cars 8 octane, together with good-
quality, synthetic oil for mixtures at a quantity of 2.2% - 2,5%.
DO NOT USE MIXTURE ALREADY DONE AT PETROL PUMPS.
When you prepare the mixture, make sure that the tank has not dirt or water
in it, filter the fuel with cotton white textile into a clean tank and then add the
oil.
Never run the engine without the air-filter, because dirt and dust raised by the
propeller can damage it.
Running- in procedure
The running-in is a key stage of the life of an engine.
Even if the high standard quality level of the machining and the exceptional
material quality currently applied in the production process suggest that there
is no need of an adjustment phase of the engine, the running-in is still a
fundamental step in its life for getting the best performance and reliability.
The parts that require a longer running time for the operation of the
propulsion and that need to get to an optimum settling are cylinder and
piston.
During the running in phase and limited to this period only the fully
synthetic oil percentage is 2,5%
All engines are tested in CORS-AIR before delivery, where we set carburetor
and idle.
We strongly advise not to modify the carburetor settings during the
engine running-in.
1. Turn on the engine and let it run at the ground for 10 minutes varying
the rpm range from 3000 to 5500 rpm, after that switch off the engine
and let it cool down for 10 minutes.
2. Turn on the engine and let it run at the ground for 15 minutes varying
the rpm range from 3000 to 6000 rpm, after that switch off the engine at
let it cool down for 15 minutes.

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3. Turn on the engine and let it run at the ground for 15 minutes varying
the rpm range from 3000 to 6500 rpm, after that switch off the engine at
let it cool down.
The throttle must be continually opened and closed, so to vary the
amount of fuel/oil mixture that lubricates all parts.
At this point, you can fly the engine normally, having care to warm it up to
0/100 C° before take-off.
For the first 5/6 hours of flight, fly the engine with cautions.
NEVER FLY T E ENGINE AT FULL T ROTTLE FOR A LONG TIME.
The engine running-in is finished, respect your engine and it will become your
trustworthy partner in flight.
CARBURETOR
Your Black Bull is equipped with a Tryton carburettor, specially adapted for
the Cors-Air engines;
It is a top quality membrane carburettor, 100% made in Italy, that grants an
optimal performance, with decreased consumption and a better atomization
of the mixture fuel/air.
It is more sensitive to setting adjustments, and it is suggested for a
competition use, or for pilots skilled in mechanics who want the best results.
CARBURETOR
SETTINGS
BLACK BULL engine
( all configurations)
L screw 30/35 minutes
H screw 2 hours + 10 minutes

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MAINTENANCE
 AFTER THE FIRST HOUR OF RUNNING, CHECK THE BELT
TENSIONING, AND IN CASE RE-TENSIONING IT AT 380/400 z
 AFTER THE FIRST 2 HOURS, TIGHTEN HEAD NUTS (IN CROSS
ORDER) WITH A TORQUE WRENCH AT 2.5 Kg.m (25Nm).
 AFTER THE FIRST 3 HOURS OF ENGINE RUNNING MAKE A NEW
BELT CHECK UP AND IN CASE RETENSIONING IT.
Please note that if you find black dust inside pinion and/or rubber inside
pinion’s groove, it means that belt is not well tensioned and need to be
tightened.
Every 20 hours check:
 The condition and gap (0,7 mm) of the spark plug electrode
 Clean the air-filter, in case you have a fuel filter before carburetor, clean
it also.
 The torque of every bolt
 The tension and condition of the reduction belt
 Fuel lines and wiring
 That the cord of the starter has no abrasions
Every 50 hours check:
 Same controls of the 20 hours and furthermore
 The torque of the engine’s crankcase nuts
 Change spark plug
 Change the petals of the reed valve
 The reduction belt and the play of the pulley and change them in case
of need
 The condition of the starter gears (version with electric start)
 Once a year (independently from flight hours) change the diaphragm of
the carburettor

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N.B.: It is advisable to keep records of all maintenance in a log book for the
engine.
It is also advisable to install an instrument (CHT) to control the head
temperature at sight, it is important because you can understand when your
engine is running at the proper temperature before taking off.
If you install also an EGT probe you will be able to check the temperature of
exhaust gas and avoid the engine seizure. The max. temperature of exhaust
gas is 5 0 C°
DO NOT EXCEED T IS TEMPERATURE
Tutorials on our web page at:
http://www.corsairmotors.com/en/download/

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TENSION OF T E REDUCTION BELT DRIVE
USE CAUTION
Attention: a belt which is “over tensioned” can do permanent damage to the
bearings inside of the pulley hubs and drive shaft.
Therefore we strongly suggest for you to follow carefully these instructions.
Before adjusting the belt take a felt pen or marker and make a small sign on
the cam shaft and on the front of the reduction plate.
This is your Zero or start point and from here you will be able to clearly see
how much you move the eccentric tensioning cam in relation to the reduction
plate.
Remember “these are Fine adjustments” and we suggest not to rotate the
cam any more than 1 mm per adjustment.
After each adjustment you can try to start the engine and check the result.
If the engine does not start well then it usually means the belt is still too loose
and is slipping - in this case repeat the operation by tensioning the belt
another 1 mm.
Consider that if the belt slips a little, but the engine still starts fine, then the
tension is correct.
Belt tension always increases automatically when the engine is running
because of thermal expansion in the pulleys.
Once you have found the correct tension, do not adjust it any more.
In case of doubts please contact your paramotor dealer – or CORS-AIR.

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To adjust the belt do the following:
 Loosen the safety bolt located high up behind the reduction mounting
plate and the side bolt.
 Once these are loosened then you can turn the cam with a n.27 mm
size wrench - careful to observe the 1 mm increments.
 Once you have finished turning the cam remember to re-tighten the
safety bolts, first the exagonal bolt, by keeping firm the cam with the
wrench, and then the side bolt.
 Should you notice any black rubber dust inside small pulley ( pinion),
your belt needs to be re-tensioned because it is loosing.
IGNITION (ONLY FOR ENGINE WIT AND START)
In case the coil and/or the handwheel must be changed, it is compulsory to
turn to your dealer or to trained personnel, even if this operation can appear
simple at the first sight, since the timing of the engine, if wrong, can change
the performance and cause damage to the engine.
To check the timing: the distance between the coil and the flywheel magnet is
0,40 mm.
CORS-AIR AND ITS RESELLERS REMAIN AT YOUR DISPOSAL FOR
EVERY INFORMATION AND ADVICE ABOUT THE USE OF THE ENGINE.

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WARRANTY
CORS-AIR engines are manufactured with top-quality material, therefore
warranty is valid also for their accessories.
DURATION OF WARRANTY
 1 YEAR beginning from the date of sell or exit from CORS-AIR
 Warranty includes spare parts and labour, transport excluded.
WARRANTY IS VOID IN T E FOLLOWING SITUATIONS:
Alterations to the engine not approved by CORS-AIR.
Wear&tear of components of the engine due to the instructions within
the product manual not being adhered to.
Accidental falls, crash or dropping of the engine or its components.
Overheating and seizure of the engine due to prolonged high speed
running of the engine, running with excessive loads, running with
inadequate loads, running with insufficient oil in the petrol (for a wrong
tuning of the carburettor) or running with petrol only (oil mixture
omitted).
The presence of dirt, sand or foreign bodies in the carburettor of the
engine.
Corrosion through bad storage of the engine or inadequate preparation
for storage of the engine.
Running the engine without an air-filter fitted to the carburettor.
Miss-assembly of engine parts or components not assembled by
CORS-AIR but by the manufacturer of the paramotor or by the end
user, supplied disassembled for packing and transport purposes,
included all electrical or electronic components including electric starter.
Corrosion of the engine or components emanating from stone chips or
any other impact or abnormal stress damage.
Work other than the maintenance set out in the product manual having
been carried out on the engine by anyone other than CORS-AIR or
official dealers.
Incidental or consequential loss or damage.
Service bulletins from CORS-AIR not having been adhered to.
Engine used for racing use.

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TROUBLE S OOTING
DON’T HOLD IDLE
SPEED OR HAS
CANNOT
REACH
IRREGULAR MAXIMUM
SPEED
SPEED
SWITCH ON/OFF
CONNECTION OF CABLE OF THE
SPARK PLUG
CORRECT SPARK PLUG GAP
CONNECTIONS OF THE ELECTRIC
PLANT
THE FUEL ARRIVES CORRECTLY
FROM THE TANK TO THE
CARBURETTOR
DISMANTLE THE SPARK
PLUG AND DRY IT
BEFORE REASSEMBLING
SPARK PLUG, TAKE OFF
THE FUEL LINE FROM
CARBURETOR AND START
THE ENGINE 2/3 TIMES
THE REED VALVE PETALS ARE
OPENED OR BROKEN
CLEAN AND ADJUST THE
CARBURETTOR
CABLE PULLING THROTTLE IS
NOT FULLY OPEN
CLEAN THE CARBURETOR NETS
inside
THERE IS NO TANK-FILTER
RESTRICTION IN THE FUEL PIPE
SPARK PLUG
CHANGE HEAD GASKET
AND THE CYLINDER GASKET
CHECK
PROBLEMS
SOLUTION
DON’T
START FLOODED HEAD IS DECARBONED

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SOME FINAL IMPORTANT ADVICE
NEVER switch on the engine with people near propeller, or to sides.
The BREAKAGE of a propeller can cause very severe hurts even several
metres away.
DO NOT keep engine at peak rpm after the take off, except for the absolutely
necessary time and for emergencies (obstacles or sudden wind).
REMEMBER that the longer the propeller is and more thrust you get but less
cooling system is granted to the engine which it will operate under stress.
So keep under control the temperature of the engine with proper instruments
(CHT under spark plug and we reccomend also EGT of the exhaust gas
check page. 5 for the correct engine temperature)
In addition, dismantle the propeller at regular intervals and check that it is
perfectly balanced, since an unbalanced propeller, even slightly, creates
micro-vibrations which are not felt by the pilot, but can damage seriously
parts of the engine with consequent breakages.
Please do NOT forget that the propeller has mass and a considerable inertial
moment, so it’s advisable not to vary suddenly the RPM of the engine, both in
flight and on the ground.
These violent stresses could cause damages to the reduction, to the engine,
to the belt and also possible deformations to the fixing holes of the propeller.
Once you have found the perfect carburation, DO NOT modify it unless you
change flying place going to much higher or lower altitudes or unless climate
and temperature are very different from the ones where you fly usually.
DO NOT FLY in bad weather conditions, you’ll fly the day after.
REMEMBER: FLIG T IS FOR FUN, NOT FOR RISKING YOUR LIFE!
AVE A GOOD FLIG T AND ENJOY YOURSELF.

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STORAGE OF T E ENGINE FOR A LONG TIME
In case the engine is not used for a long time, act like this:
 Empty the fuel tank, included the fuel lines and the carburetor.
 Disassemble the battery (version with electric start).
 Unscrew the spark plug and pour into the hole a teaspoon of oil for
engines, then re-install the spark plug letting the propeller turn slowly by
hand for 2 or 3 times completely.
 Disassemble the propeller.
 Loosen the reduction belt.
 Plug the hole of the exhaust pipe.
 Cover everything with a cloth and put it in a dry place.
 Once a month charge the battery and let the pinion of the drive shaft
turn by hand 2 or 3 times completely.

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Instructions for assembly:
- Put some light or medium Loctite on the 4/6 pins and tighten them completely
- Always use the aluminium disk
- Insert the propeller
- Insert the propeller disk
- Insert the central bolt and tighten it at about 1,5 Kg (15Nm), checking that the clip
can be inserted
- Insert the safety clip

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ELECTRIC SYSTEM FOR BLACK BULL WIT REC ARGING KIT FOR
LEAD OR LIT IUM BATTERY
NOTE FOR LITHIUM BATTERY:
1.1 LIMITED VOLTAGE: 13.5÷14.5VDC
1.2 REGULATOR MUST BE DISCONNECTED BY BATTERY WHEN ENGINE STOPPED
1.3 WHEN REVERSED CONNECTED TO BATTERY, REGULATOR WILL FAIL
1.4 WHEN REGULATOR USED WITHOUT BATTERY IT WILL FAIL
1.5 UNIT TEMPERATURE WOR ING RANGE: -10° C TO 50° C (on unit surface)
BLUE WIRE TO THE COIL
BLACK WIRE TO THE NEGATIVE PIN O
F BATTERY
RED WIRE TO POSITIVE PIN
OF BATTERY
Note for lead battery:
1.1 limited voltage: 16VDC
1.2 when reversed connected to battery, regulator will fail
1.3 when regulator used without battery it will fail
1.4 unit temperature working range: -10°C to 50°C (on unit surfare)
[

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NOTES:
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