ULPOWER UL260 User manual

UL26o
UL35o
UL39o
UL52o
Operating
Manual
M0310: OM 260 - 520A01 Revision No: 04 Date: 2021-11-18

Operating Manual ULPOWER UL260,UL350,UL390,UL520
M0310: OM 260 - 520A01 Revision No: 04 Date: 2021-11-18 Page: 1 of 23
Preface
Thank you for choosing ULPower Aero Engines to power your aircraft.
This Manual will provide you with basic information on safe engine operations / safe flights .
We recommend to study this manual carefully , before starting the engine for the first time.
If you are unsure about the procedures mentioned in this manual, please contact a ULPower
authorised sales or service point.
We hope you will enjoy flying your ULPower-ed aircraft.
Remarks
The diagrams and other pictures in this manual show the typical construction. They may not
represent in full detail or the exact shape of the parts which have the same or similar function.
Specifications are given in the SI metric system with the USA (Imperial system) equivalent in
parenthesis. Where precise accuracy is not required, some conversions are rounded off for easier
use.
In addition to this Operating Manual, please refer to the following:
Installation Manual
Technical Data document
Installation checklist
Trouble shooting manual
Illustrated Parts Catalogue
Propeller flanges document
Maintenance Manual
Please make sure you have the latest version available of the applicable manual.
Modifications
The information and components/system descriptions contained in this Operating Manual are
correct at the time of publication. ULPower, however, maintains a policy of continuous
improvement of its products without imposing upon itself any obligation to install them on its
products previously manufactured.
ULPower reserves the right at any time to discontinue or change specifications, designs, features,
models or equipment without incurring obligation.
Please contact your dealer or check the manufacturers website (http://www.ULPower.com) for any
updates or changes concerning the engine and its manuals.
Engine serial number
On all enquiries or spare parts orders, always indicate the engine serial number. The serial number
(6 digits) can be found on top of the engine near to cylinder 2.
X
X
X
X
X
X

Operating Manual ULPOWER UL260,UL350,UL390,UL520
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Repeating symbols
This manual uses the following symbols to emphasize particular information. These indications are
important and must be respected.
WARNING : Identifies an instruction which, if not followed, may cause serious injury
including the possibility of death.
Attention : Denotes an instruction which, if not followed, may severely damage the engine
or other components.
Note : Indicates supplementary information which may be needed to fully complete or
understand an instruction.

Operating Manual ULPOWER UL260,UL350,UL390,UL520
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Safety information
The engine should only be installed and operated by persons familiar with the use of the engine
and informed with regard to possible hazards.
Familiarize yourself with the installation, maintenance and operational limits of your ULPower
engine. Failure to follow the instructions in these manuals can result in a serious malfunction or
loss of power in flight , with possible loss of life, injury or damage to the equipment. Limit
yourself to the operations/ maintenance mentioned in ULPower manuals. If you are uncertain
and/or in need of extra information please contact a ULPower authorized sales or service
centre.
This non certified engine is designed for possible application on aircraft used in VFR conditions
which have the capabilities of controlled gliding without engine power.
You should be aware that any engine may malfunction at any time. This could lead to a crash
landing and possible severe injury or even death. For this reason, we recommend strict
compliance with the maintenance and operation manuals and any additional information which
may be given to you by your authorized sales or service centre .
Never fly the aircraft equipped with this engine at locations, airspeeds, altitudes, or other
circumstances from which a successful no-power landing cannot be made, after sudden engine
stoppage.
Make sure you know what engine you are using. Only engines UL260iSA /UL350iSA/
UL390iSA/UL520iSA are suited for acrobatics (inverted flight, etc.).
It should be clear that the choice, selection and use of this particular engine on any aircraft is at
the sole discretion and responsibility of the aircraft manufacturer, assembler and owner/user.
ULPower makes no warranty or representation on the suitability of its engine's use on any
particular aircraft. Furthermore, ULPower makes no warranty or representation of this engine's
suitability with any other part, component or system which may be selected by the aircraft
manufacturer, assembler or user for aircraft application.
Never (test) run the engine without a propeller or flywheel as this will inevitably cause engine
damage and present a hazard of explosion.
Propeller/flywheel and its attachment with a moment of inertia in excess of the specified value
must not be used and releases engine manufacturer from any liability.
Improper engine installation and use of unsuitable piping for fuel-, cooling- ,lubricating - , intake
and exhaust system releases engine manufacturer from any liability.
Unauthorized modifications of engine, its components, ECU, etc. will automatically exclude any
liability of the manufacturer for direct, indirect and/or consequential damage.
Spare parts must meet with the requirements defined by the engine manufacturer. This is only
warranted by use of genuine ULPower spare parts and/or accessories. They are available at the
authorized ULPower distribution- and service partners.
The use of anything other than genuine ULPower spare parts and/or accessories will render any
warranty relating to this engine null and void.
Respect all government or local rules pertaining to flight operation in your flying area. Fly only
when and where conditions, topography, and airspeeds are safe.
Select and use proper and calibrated aircraft instrumentation. This instrumentation is not
included with the basic ULPower engine.
Before flight, ensure that all engine controls are operational and engine is airworthy. Make sure
all controls can be reached in case of an emergency.

Operating Manual ULPOWER UL260,UL350,UL390,UL520
M0310: OM 260 - 520A01 Revision No: 04 Date: 2021-11-18 Page: 4 of 23
Unless in a run up area, never run the engine with the propeller turning while on the ground. Do
not operate engine if bystanders are close.
In the interest of safety, the aircraft must not be left unattended while the engine is running.
Keep an engine log and respect engine and aircraft maintenance schedules. Keep the engine in
top operating condition at all times. Do not operate any aircraft which is not properly maintained
or has engine operating irregularities which have not been corrected.
To eliminate possible injury or damage, ensure any loose equipment or tools are properly secured
before starting the engine.
When in storage protect the engine, fuel, lubrication, induction and exhaust system from
contamination and exposure.
Never operate the engine without sufficient quantities of lubricating oil, fuel and cooling air.
Allow the engine to cool at idle for several minutes before turning off the engine.

Operating Manual ULPOWER UL260,UL350,UL390,UL520
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Table of contents
Preface ..................................................................................................................1
Remarks...............................................................................................................1
Modifications.........................................................................................................1
Engine serial number ...............................................................................................1
Repeating symbols ..................................................................................................2
Safety information....................................................................................................3
Table of contents .....................................................................................................5
Description of systems...............................................................................................7
Lubricant system ....................................................................................................7
Fuel system ..........................................................................................................7
Electronic Engine Management system..........................................................................7
Cooling system.......................................................................................................8
Warning lights .........................................................................................................9
Check light ...........................................................................................................9
Battery low...........................................................................................................9
General operating limits .......................................................................................... 10
Running in .......................................................................................................... 10
Performance (in ISA - International standard atmosphere - conditions) ............................... 11
Acceleration ....................................................................................................... 11
Deviation from bank angle ...................................................................................... 11
Oil level............................................................................................................. 11
Operation limits ................................................................................................... 12
*Electrical power ................................................................................................. 13
**Manifold air temperature ...................................................................................... 13
***Rail fuel pressure ............................................................................................... 13
+Oil pressure ....................................................................................................... 14
++EGT ................................................................................................................ 14
+++Cylinder head temperature................................................................................... 14
++++Turbo pressure................................................................................................. 14
Operating media .................................................................................................... 15
Fuel.................................................................................................................. 15
Lubricants .......................................................................................................... 15
Standard operation ................................................................................................. 16
Daily/Pre-flight checks........................................................................................... 16
Engine start ........................................................................................................ 16
Prior to take-off................................................................................................... 17
Warming up period:............................................................................................ 17
Idle speed:....................................................................................................... 17
Throttle response: ............................................................................................. 17
Ignition test: .................................................................................................... 17
Take-off and cruise ............................................................................................... 17
Engine shut-down ................................................................................................. 18
Engine storage ..................................................................................................... 18
Abnormal operation ................................................................................................ 19
Abnormal running on ignition check ........................................................................... 19
Sudden engine stop ............................................................................................... 19
Reaching maximum engine speed .............................................................................. 19
Exceeding of max. admissible cylinder head temperature ................................................ 20
Exceeding of max. admissible oil temperature .............................................................. 20
Oil pressure below minimum.................................................................................... 20

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Exceeding of max. admissible oil pressure ................................................................... 20
Relative fuel pressure deviates from normal ................................................................ 21
Derivation of turbo pressure (if applicable).................................................................. 21
Single CHT and/or EGT drop .................................................................................... 21
Knocking ............................................................................................................ 21
Low battery voltage .............................................................................................. 22
Prop Strike ......................................................................................................... 22
Revision ............................................................................................................... 23

Operating Manual ULPOWER UL260,UL350,UL390,UL520
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Description of systems
Lubricant system
The high volume oil pump, with integrated pressure release valve, takes up oil through a coarse
filter on the oil pick up tube which is located in the wet oil sump.
An impressive amount of pressurized oil is pumped through the mandatory oil cooler (not included
as standard with the engine) and oil filter before it enters the main oil gallery where it lubricates
the essential parts of the engine. Excessive oil accumulates back into the oil sump.
Fuel system
Fuel from the tanks is guided through a coarse filter before reaching the electrical fuel pump. This
high volume fuel pump (120l/h or 32USgal/h) creates a pressurized fuel flow and pumps fuel
through a fuel fine filter towards the injectors and the integrated fuel pressure regulator.
Afterwards excessive fuel is returned to the fuel tank.
Electronic Engine Management system
All ULPower engines are equipped with an electronic injection and ignition system.
The ECU automatically sets the fuel mixture and ignition timing (multiple times per second!). As a
result, in the cockpit, there is no choke, no primer, no carb heat, and no mixture, just a single lever
: the throttle. It will even fine tune the fuel flow to compensate for changes in barometric pressure
as well as inlet air temperature in the inlet manifold/airbox. The fuel mixture and ignition timing is
controlled for operations up to 18.000 ft.
With timing corrections to avoid detonation and a built-in rev-limiter,(3.300rpm on most naturally
aspirated engines or 2.700 RPM on turbo engines) the ECU not only ensures efficient power to fuel
consumption at any given operating condition.
Note: The engine is managed electronically, consequently, the engine cannot run without a
working electrical system.
The UL 260 / UL350 engine and fuel pump use maximum continuous 15 Amps
1
to operate.
The UL 390 / UL520 engine and fuel pump use maximum continuous 21 Amps1to operate.
Note: The UL260/UL350 engine comes standard with an integrated AC generator with external
rectifier/regulator that can supply up to 30 Amps. The UL390/UL520 generator can supply
up to 50 Amps. This should be sufficient to charge the battery while the standard engine is
operating and other electrical aircraft systems are in use. Electrical system should be
monitored to ensure sufficient electrical power is available to maintain battery charge at
all times. In the event of alternator failure, in cockpit non-essential electrical systems
should be switched off to maximize engine operation time whilst seeking an immediate
landing site.
1
Operation : one pump, dual ignition, single ECU, 3300 RPM ,13.5V

Operating Manual ULPOWER UL260,UL350,UL390,UL520
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Cooling system
All engines are air and oil cooled. Installing the ram air ducts that come with the engine, is
mandatory. See installation manual for more info on this subject
The installation of an oil cooler is mandatory as the oil is not only used to lubricate but also to cool
the engine. See installation manual for more info on this subject.

Operating Manual ULPOWER UL260,UL350,UL390,UL520
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Warning lights
The ECU provides output for two standard warning lights: Battery low (below 12.7V) and (engine)
Check light.
Note: It is very important that your check light and battery low light is installed in accordance
with the installation manual.
Check light
Note: The check light can be tested by switching power “ON” to the ECU: If installed correctly
the check light will come up for 2 seconds (only for engines with a serial number higher
than 191401) . You can do an additional test by disconnecting one of the sensors; if the
installation is ok, the check light will come up.
When there is a problem with one of the following sensors, the CHECK light will come on
•Oil temperature sensor
•Inlet air temperature sensor
•Throttle position sensor
•Altitude sensor (Integrated in ECU)
•Hall sensor engine start (Sync/CPS)
Attention: In the event of the check light coming on, the engine will continue to run, however,
it may not be running optimally due to the use of default values in the ECU-map.
This might increase the fuel burn. Continue the flight and resolve the issue before
next flight.
Battery low
If the voltage at the ECU drops below 12.7 volts, the ‘Battery low’ LED will come on. It will
disappear again when 13V is reached.
Battery low
Check light

Operating Manual ULPOWER UL260,UL350,UL390,UL520
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General operating limits
Naturally aspirated engine
Turbo engine
RPM
RPM
Maximum
3300 (3500 iHPS)
2700
Recommended cruise
2200-2800
2200-2500
Recommended idle speed
850
850
Min. idle speed
700
700
Requirements about RPM settings
Min. static at WOT2
2550
2400
Min. take OFF at WOT
2800
2300
Min. WOT straight and level
2900
2400
Running in
a) All engines
-No need to use special run-in oil.
-To run in a new engine: It is important that the engine runs as much as possible at
operation temperature (Oil temperature 80 to 100°C (176-212°F), CHT 110 to 140°C (230-
284°F) and at ± 80% of the max. power during the first 15 hours.
This means: For the first 15 hours: Avoid continuous running at full power. But on the other
hand do not run the engine for a long time at idle on the ground. Go flying : after take-off
and initial climb (full power) reduce the power to approximately 80%
Note: AS A GUIDELINE : The power output can be checked in several ways:
-EFIS/ULRead : Read out ± 72% throttle position = ± 80 % Power output
-Throttle level : (linear 0-100%) = ± 80% throttle position = ± 80 % Power output
-Manifold pressure :
oNaturally aspirated: ± 80-85 kPa (± 23.6-25.1 inHg) = ± 80% Power output
oTurbo : ± 105-110 kPa (± 31-32 inHg) = ± 80% Power output
b) Aerobatic engine
3
-Don’t fly any aerobatic manoeuvres during the first 15 flying hours
-Follow maintenance manual and add ULP Acro + oil additive (ULP Part no. L0100120) every
oil change starting from the first 15 hours oil change
2
WOT : Wide Open Throttle
3
Only available for naturally aspirated engines

Operating Manual ULPOWER UL260,UL350,UL390,UL520
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Performance (in ISA - International standard atmosphere - conditions)
Engine
Maximum
peak HP
(for 5
minutes)
Maximum
continuous HP
Fixed pitch prop.
Maximum
continuous RPM
VP/CS-prop.
Maximum continuous
MAP
Indicated Manifold Air Pressure
-bar [inHg]
Maximum RPM
UL 260i
97
87
2800
0.88 [26]
3300
UL 260iS(a)
107
95
2800
0.88 [26]
3300
UL 350i
118
112
2800
0.88 [26]
3300
UL 350iS(a)
130
123
2800
0.88 [26]
3300
UL 350iHPS
145
131
3000
0.88 [26]
3500
UL 390i
140
125
2800
0.91 [27]
3300
UL 390iS(a)
160
143
2800
0.91 [27]
3300
UL 520i
180
170
2800
0.91 [27]
3300
UL 520iS(a)
200
180
2800
0.91 [27]
3300
UL 520T
220
200
2700
1.22 [36]
2700
Table 1 : Performance
Acceleration
Only operate the engine at zero gravity and in negative "g" conditions during a limited amount of
time. Positive oil pressure must be maintained at all times.
Deviation from bank angle
Value to which the wet sump (normal oil level) lubrication system warrants lubrication in positive
"g" flight situation
Max. ....................................... 35°(non-aerobatic engines).
Oil level
Engine
Type
Max. oil level
Min. oil level
UL260/UL350
i/iF/iS/iHPS
3.5 litres (3.7 quarts)
2.5 litres (2.6 quarts)
iSA
4.5 litres (4.7 quarts)
3.5 litres (3.7 quarts)
UL390/UL520
i/iS/iSRR/iHPS
4.5 litres (4.7 quarts)
3.5 litres (3.7 quarts)
iSA
5.5 litres (5.8 quarts)
4.5 litres (4.7 quarts)
Attention: The marks on the dipstick (min-max) are only valid when the engine is horizontal !
Always ensure that the plane is level before checking the oil level.

Operating Manual ULPOWER UL260,UL350,UL390,UL520
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Operation limits
The operational limits for naturally aspirated and turbocharged engines are the same, with the exception of manifold air temperature (and turbo
pressure).
Value
Volts
V
*
Oil Temp
C / F
Manifold Air
Temperature
Naturally
aspirated
C / F **
Manifold Air
Temperature
Turbo
C / F **
Fuel Pressure
(rail sensor)
Bar / PSI ***
Oil
Pressure
Bar / PSI
+
EGT
C / F
++
CHT
C / F
+++
Outside Air
Temperature
C/F
Turbo
pressure
Bar/PSI ++++
Turbo
ECU (Ambient)
Temperature
C/F
Min:
Red
12.5V
50°C
122°F
-30°C
-13°F
-30°C
-13°F
2.4Bar
35PSI
0.7 –1Bar
10 –15PSI
300°C
573°F
-25°C
-13°F
++++
-40°C
-40°F
Yellow
12.5 –12.7V
50 –80°C
122 176°F
1 –2Bar
15 –29PSI
300 –400°C
572 –752°F
<50°C
<122°F
++++
Green
12.7 –14.5V
80 –100°C
176 –212°F
-30 –40°C
-13 –104°F
-30 –60°C
-13 –140°F
2.4 –3.4Bar
35 –49PSI
2 –5Bar
29 –73PSI
400 –850°C
752 –1562°F
50 –160°C
122 –320°F
-25 –50°C
-13 –122°F
1.32-1.38Bar
19.1 –20.0PSI
-40 –65°C
-40°F –149°F
Yellow
14.5 –15.5V
100 –120°C
212 –248°F
40 –60°C
104 –140°F
60 –75°C
140 –167°F
3.4 –3.8Bar
49 –55PSI
5 –8Bar
73 –116PSI
850 –880°C
1562 –1616°F
160 –180°C
320 –356°F
1.38-1.40Bar
20.0 –20.3PSI
Max:
Red
15.5V
120°C
248°F
60°C
140°F
75°C
167°F
3.8Bar
55PSI
8Bar
116PSI
880°C
1616°F
180°C
356°F
50°C
122°F
1.40Bar
20.3PSI
65°C
149°F
WARNING: Make sure operating limits are respected at all times. Running the engine outside of the limits set by the manufacturer may severely
damage the engine and will render any warranty relating to this engine null and void.

Operating Manual ULPOWER UL260,UL350,UL390,UL520
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*Electrical power
Make sure the battery is fully charged before take-off (engine not running) with an output voltage
min = 12.7 VDC. When the engine is running, the (alternator) voltage must be at least 13V.
When the ‘battery low’warning light (see above) is activated during flight (indication
alternator/regulator failure),the flight time with a full battery is ≥30 min
4
. At around 10V the ECU
stops functioning and the engine stops.
Attention:Never use a “booster” (quick battery charger) to start the engine. Change the
battery to avoid jump starting.
**Manifold air temperature
Note: We advise to bring fresh air from outside the cowling to the inlet air filter/manifold. For
turbo engines, we advise to install a suitable intercooler (see installation manual).
Engine
Naturally aspirated
Turbocharged/normalized
Max. at start
60°C (140°F)5
75°C(167°F)
Max. at take-off
50°C (122°F) 5
70°C (158°F)
Max. in flight
40°C ( 104°F)5
60°C (140°F)
***Rail fuel pressure
Rail fuel pressure is the difference or delta pressure ABOVE the Manifold Air Pressure (M.A.P. may
be measured by optional sensor)
Condition
Remarks
A
ECU ON, Engine OFF, Fuel pump(s) ON
Fuel pressure (FP) 3 –3.4 bar (43.5 –49 PSI)
Fuel pressure must be stable
B
ECU ON, Engine ON, Fuel pump(s) ON
FP depends on MAP/Throttle position
Blue line ideal FP
Idle ±2.6 bar (35 PSI)
WOT ±3.0 bar (43.5 PSI) nat. asp. engines
WOT ±3.3 bar (48 PSI) turbo engines
NOTE : Fuel pressure can be higher when using both fuel pumps.
4
Fully charged healthy battery. Depending on installation, used battery/batteries, aircraft electrical system,… .
5
Rule of thumb : ambient temperature + 10°C, with respect to maximum manifold air temperatures
A
B
B
A
A

Operating Manual ULPOWER UL260,UL350,UL390,UL520
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+Oil pressure
Condition
Pressure
Engine cold start
Max. 8 bar (115 PSI)
Above 2000 RPM
2 –5 bar (27 –75 PSI)
Below 900 RPM (hot oil)
Min 0.7 bar (10 PSI)
++EGT
EGT varies upon delivered power.
Most important is that all EGT values are +/- equal. EGT values should normally be within 100°C of
each other, depending on installation and operations
+++Cylinder head temperature
CHT values must remain within 20°C of each other.
++++Turbo pressure
Turbo pressure must be in ‘green zone’ AND stable at min. 2200 RPM and min. 40% throttle position.

Operating Manual ULPOWER UL260,UL350,UL390,UL520
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Operating media
Fuel
The engine has been tested to E20, however, fuel lines, fuel tanks and other components in your
installation may not be suitable for ethanol containing fuels.
UL260i / UL350i / UL390i / UL520i
Note: Red valve covers
AVGAS UL91 or regular unleaded automotive fuel with a minimum of 95 octane RON = 91 AKI
(USA/Canada) should be used to operate these engines.
UL260iS / UL350iS / UL350iHPS / UL390iS / UL520iS / UL520T
Note: black valve covers (blue for iHPS engines)
AVGAS UL91 or regular unleaded automotive fuel with a minimum of 97/98 octane RON = 93 AKI
(USA/Canada) should be used to operate these engines.
AVGAS 100 LL may be used on the above engines if regular fuel is not available.
Note: Due to higher lead content in AVGAS 100 LL, the wear of the valve and valve seats, the
deposits in combustion chamber and lead sentiments in the lubrication system will increase.
Attention: Fuel storage for a long time in the fuel tanks start to degrade. Avoid running the
engine with old fuel and replace the fuel in the tanks if necessary.
Lubricants
We recommend the use of Motul 300V(15W50) oil or Aeroshell SAE15W50 oil.
Do not use special brake-in oils.
Note : For Aerobatic engines : Add a bottle ULP Acro+oil (part no. : L0100120). This is an additive
that was developed by ULPower and is not available on the general market.
DON’T ADD THIS DURING THE FIRST 15 HOURS. Only to be added after the first oil change.
Attention: If AVGAS 100 LL is used frequently, we recommend to use only the semi synthetic oil
“Aeroshell SAE15W50” and change oil more frequently (see maintenance manual)

Operating Manual ULPOWER UL260,UL350,UL390,UL520
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Standard operation
Daily/Pre-flight checks
WARNING: Conduct checks on cold engines only to avoid risk of burns and scalds!
Make sure ignition is turned OFF when inspecting the engine. Have the cockpit
occupied by a competent person.
Turn the propeller by hand in the direction of engine rotation several times and observe engine for
odd noises or excessive resistance and normal compression. If irregular, check troubleshoot manual
or seek technical assistance.
Check that all spark plugs, leads and electrical connections are secure.
Verify the free movement of the throttle cable over the complete range. Check from cockpit.
Check for any oil and fuel leaks.
Check integrity and security of oil- and fuel- lines, electrical wiring, cooling hoses, baffles, filters,
oil cooler ,intercooler as may apply.
Note: Fuel pump must be switched on to ensure the fuel lines are under pressure.
Check oil level and replenish if necessary .
Note: Make sure the oil level is between the min. and max. marks. Before starting a long flight
replenish up to max. level. Difference in oil quantity between min. and max. level is 1
litre.(1 quarts)
Inspect exhaust system for damage, leakage and general condition.
WARNING: Do not fly your aircraft or operate your engine unless you are satisfied it is
airworthy.
Engine start
WARNING: Do not start the engine if a person is close to the aircraft.
1. Fuel tap ............................... OPEN
2. Master switch ......................... ON
3. ECU ..................................... ON
3. Ignition Coils .......................... ON
4. Fuel pump ............................. ON
Attention:Run the fuel pumps for a few seconds before starting the engine to avoid vapour lock
and ensure fresh fuel from the tank is available. Fuel pressure must be stable and
must be minimal 3 bar (43.5psi).
5. Throttle lever ........................ set to idle + approximately 10% of throttle movement
6. Starter ................................. ENGAGE
Attention: Activate starter for max. 5 seconds only (without interruption), followed by a
cooling period of 15 seconds if restart is necessary. Do not engage starter whilst the
engine is running. Wait until complete stop of engine.
As soon as engine is running adjust throttle to achieve smooth running at approximately 1200 rpm.
Check if oil pressure has risen within 5 seconds (if not: shut down the engine). Verify if oil pressure
remains within the limits.

Operating Manual ULPOWER UL260,UL350,UL390,UL520
M0310: OM 260 - 520A01 Revision No: 04 Date: 2021-11-18 Page: 17 of 23
Attention: Increase of engine speed is only permitted when oil pressure reading remains below
maximum.
Prior to take-off
Warming up period:
Start warming up period with engine running between 1200 and 1500 rpm, duration depending on
ambient temperature, until:
oil temperature reaches at least 50°C (122°F)
cylinder head temperatures are at least 50°C (122°F)
Attention: Always check temperatures and pressures are within limits.
Idle speed:
When warm, engine can be set at idle speed.
Note: Although engine idle speeds of 700 rpm can be obtained, we recommend the ground idle to
be at least 850 rpm for smooth running.
Throttle response:
When ready for take-off, as part of your power checks, do a short full throttle ground test. No
irregularities may occur.
Attention: Boost pressure must be within range
Fuel pressure must be within range
Note: Check with aircraft/propeller operating handbook, since engine speed depends on the
propeller used.
Ignition test:
The engine is equipped with double redundant ignition. Switch off one ignition coil at the time and
verify that engine still operates normally on either of ignition coils separately.
Attention: RPM difference between running with coil 1, with coil 2 or both may not exceed 5%
of nominal RPM
Take-off and cruise
Climbing with the engine at maximum take-off power (see ‘Table 1 : Performance’ ) is permitted
during a time period of max. 5 minutes.
In cruise, keep the engine power below the maximum continuous power settings (see ‘Table 1 :
Performance’) for continuous operation.
Attention: Observe that all temperatures and pressures remain within limits at all times. If
engine limit values are at/or approaching red line, reduce power and land as soon as
possible if unable to establish flight within acceptable limits.

Operating Manual ULPOWER UL260,UL350,UL390,UL520
M0310: OM 260 - 520A01 Revision No: 04 Date: 2021-11-18 Page: 18 of 23
Do not fly your aircraft if the oil temperature has not reached normal operating values yet (50°C /
122°F). Low operating temperatures may not eliminate any accumulated water in the engine. The
presence of condensate water in the lubrication system has a bad influence on the oil quality.
Engine shut-down
Attention: For turbocharged engines, after coming to a complete stand-still on the apron,
ensure an adequate idle running cool-down period (2 min) to prevent carbon/glazing
deposits from overheated oil. Hard oil residues can obstruct parts of the oil system
and lead to damage
Shut down the engine by switching off power to ECU before cutting off fuel/ignition.
Under normal circumstances, the descent and taxiing may have cooled the engine down, however,
the two minutes idle time should still be respected.
Note: If temperatures are still at the high end of the limits, allow longer engine idling , to cool
the engine down before shut-down.
Engine storage
For long out-of-service periods we recommend the following to protect the engine against corrosion.
-Let engine run until warm, then change oil
-Remove the air inlet filter and insert approx. 30 cm3 (1 Fl oz) of corrosion inhibiting oil into
the inlet with the engine running at increased idle speed
-Shut off engine
-Close all openings on the cold engine, like exhaust end pipe, air intake (throttle), venting
tube.
-Spray all steel external engine parts with corrosion inhibiting oil
-Store the engine as dry as possible