D-MOTOR LF26 User manual

The Light Weight Engine Houtekietstraat 11
B-8540 Deerlijk, Belgium
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D-MOTOR International © AIRCRAFT ENGINE
ENGINE OWNERS MANUAL
TYPE LF26 - 4 Cylinder Engine
Publication : 2019.3/LF26
© D-Motor International bvba, February 2019

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Succession Notice
This manual is a revision of the previous manual published in 2013 and any revisons there of. Information within this document
replace the instructions of previous D-Motor International Publications –Engine Owners Manual.
Effective Changes for this manual / document
February 2019 V1
August 2019 v3 (KGhekiere)
March 2019 V2
November, 2019 V3 (KGhekiere)
Published and printed in Belgium by D-Motor International, bvba.
Copyright ©2013,2015,2019 D-Motor International, bvba.
All rights reserved.
This material may not be reprinted, republished, broadcast, or
otherwise altered without the publisher's written permission. This manual is provided without
express, statutory, or implied warranties. The publisher will not be held liable for any damages
caused by or alleged to be caused by use, misuse, abuse, or misinterpretation of the contents.
Content is subject to change without notice. Other products and companies mentioned herein
may be trademarks of the respective owners.

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Contents
Blank Page (intentional) .......................................................................................................................... 5
INTRODUCTION ....................................................................................................................................... 6
D-MOTOR Engines.............................................................................................................................. 6
SCOPE AND PURPOSE OF THIS DOCUMENT........................................................................................ 6
Warning............................................................................................................................................... 7
Advisories ............................................................................................................................................ 7
Order of Precedence ........................................................................................................................... 7
Updates/Changes Distribution............................................................................................................ 8
Suggestions and corrections ............................................................................................................... 8
Contact Information............................................................................................................................ 8
TOA (Table of Amandments)............................................................................................................... 9
SAFETY INFORMATION.......................................................................................................................... 10
MAIN SECTION....................................................................................................................................... 11
Technical Sheet LF26 type D-Motor Engine ...................................................................................... 11
Operating limits............................................................................................................................... 13
Description ........................................................................................................................................ 15
ENGINE OPERATION.......................................................................................................................... 19
Engine start.................................................................................................................................... 19
Motor STOP ................................................................................................................................... 21
ENGINE Checking........................................................................................................................... 21
Emergency Procedures.................................................................................................................. 22
ECU ERROR MESSAGES.................................................................................................................. 24
Safety / Avoiding failures .............................................................................................................. 25
Loss of Cooling liquid.................................................................................................................... 25
Oil Supply....................................................................................................................................... 26
Throttle adjustments..................................................................................................................... 27
Fuel Supply .................................................................................................................................... 28
Important Information about fuels and lubricants : ..................................................................... 29
Power Supply................................................................................................................................. 30
Control and function test of the power supply............................................................................. 30
Spark plugs .................................................................................................................................... 31
TABLE FOR TORQUE VALUES......................................................................................................... 31
Performance Curve of the LF26 Engine......................................................................................... 34
Periodic inspections .......................................................................................................................... 35

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First 25 & 50-hour-inspection ....................................................................................................... 35
100-hour-inspection or annually................................................................................................... 35
200-hour-inspection...................................................................................................................... 35
Preservation of the engine for long term storage............................................................................. 36
Winter operation............................................................................................................................... 37
Care of the electrical system......................................................................................................... 37
Cold starting procedures............................................................................................................... 37
TROUBLE SHOOTING ......................................................................................................................... 37
Engine does not fire ...................................................................................................................... 37
Warm engine shows irregular idling ............................................................................................. 38
Engine runs erratic or misfires occasionally.................................................................................. 38
Engine overheats, Oil temperature over 100 deg.C (212 deg.F)................................................... 38
The engine does not develop full power....................................................................................... 39
Low oil pressure ............................................................................................................................ 39
The engine does not stop immediately......................................................................................... 40
Excessive oil consumption............................................................................................................. 40
Engine « knocks ».......................................................................................................................... 40
Engine hard to start at low temperatures..................................................................................... 40
OVERHAULS....................................................................................................................................... 41
Major inspections at TBO.............................................................................................................. 41
Major repairs and major modifications......................................................................................... 41
ENGINE REGISTRATION CARD –WARRANTY ACTIVATION................................................................ 42
Checklist parts ................................................................................................................................... 43
Blank Page (intentional) ........................................................................................................................ 48

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Blank Page (intentional)

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INTRODUCTION
D-MOTOR Engines
D-Motor LF 26 4 cylinder and LF39 6 cylinder engines are direct drive 100% water cooled boxer side
valve engines. The engines incorporate multi-point fuel injection controlled by an advanced twin ECU
control system which is performance mapped with Lambda sensing.
A 300W/25A generator is fully integrated as standard fitment; the oil and coolant pumps are directly
driven by the camshaft. The fuel pressure is held at a constant level with a pressure regulator, which
is connected to the fuel recirculating system. Air inlet preheating is not required and not installed.
The entire motor is controlled and monitored by the ECU (Electronic Control Unit). A second ECU is
standard, battery and fuel pump can be installed as a redundant system.
D Motor aircraft engines are a Premium Quality European Product designed and produced in Belgium
https://www.d-motor.eu
SCOPE AND PURPOSE OF THIS DOCUMENT
This manual gives instruction and guidance for engine preparation, installation, and operation of the
LF26 and LF39 aircraft engines. The installation instructions within this manual are basic guidelines.
When installing the engine in the airframe, follow the airframe manufacturer’s installation
instructions. Refer to the D-Motor Engine Service and Installation manual for required maintenance
(service information) such as: oil changes, oil top up, oil filter replacement, routine time limited-
interval inspections, routine service, spark plug replacement/inspection procedures, cylinder
inspection, fuel system inspection, and scheduled servicing procedures. For airworthiness limitations,
guidelines to fault finding and for procedures to replace components, disassembley and re-
assembley of the engine, refer to the D-Motor Engine Maintenance Manual. For spare parts
information, refer to the D-Motor Illustrated Parts Catalog.

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Warning
This is a non-certified aircraft engine ; the possibility of engine stoppage exists at all times. Do not
operate this engine over densely populated areas. Do not operate this engine over terrain where a
safe, power off landing cannot be performed.
The operation and maintenance instructions supplied with this engine must be followed at all times.
Flying any aircraft involves the risk of injury or death, building and maintaining your own aircraft
requires great personal responsibility.
Advisories
This document utilizes three types of advisories; defined as follows:
WARNING
A warning emphasizes information which, if disregarded, could result in severe injury to
personnel or equipment failure.
CAUTION
Emphasizes certain information or instructions, which if disregarded, may result in damage to
the engine or accessories.
NOTE
Provides special interest information, which may facilitate performance of a procedure or
operation of equipment.
Warnings and cautions precede the steps to which they apply; notes are placed in the manner which provides the greatest
clarity. Warnings, cautions, and notes do not impose undue restrictions. Failure to heed advisories will likely result in the
undesirable or unsafe conditions the advisory was intended to prevent. Advisories are inserted to ensure maximum safety,
efficiency, and performance. Abuse, misuse, or neglect of equipment can cause eventual engine malfunction or failure.
Order of Precedence
WARNING

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The aircraft operator must use the airframe manufacturer’s operating instructions found in the Airplane Flight Manual/
Pilot’s Operating Handbook (AFM/POH) while operating the aircraft unless the AFM/POH directs otherwise.
Updates/Changes Distribution
Document updates are available from our web site upon notification of official document approval.
Printed publication subscribers receive printed changes and revisions as they are released.
Document revisions are released if the update changes more than 50% of the contents of a
publication. Revisions replace the previous version of a publication from cover to cover.
Minor corrections are released as change pages to the original publication, identified with a change
number and effective change date in the page footer. Information on the page that changed from
the previous edition is identified by a vertical, six-point black line referred to as a “change bar” in the
outside margin of the page. A page change replaces only the previous edition of the affected page.
Suggestions and corrections
D-Motor International solicits and encourages user comments regarding suggested changes to this
manual. Direct recommended changes or questions to the attention of “Publications” at the address
listed in this section, “Contact Information” or send comments via e-mail to [email protected]. Notify
our Customer Service Department immediately, using our telephone number, if you discover
incorrect information which adversely affects safety !! Thank you !!
Contact Information
D-Motor International factory representatives are available to answer technical questions and
encourage suggestions regarding products, parts, or service. If customers have an inquiry or require
technical assistance, they should contact their Regional D-Motor Dealer/Distributor or Field
Representative. To contact a Factory Representative, refer to the contact information below:
D-Motor International, bvba
Houtekiestraat 11
B-8540 DEERLIJK

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BELGIUM
Customer service department : [phone]
[e-mail] https://www.d-motor.eu
TOA (Table of Amandments)
Current
N°
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Page
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approval
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inclusion
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INTRO
Before operating the engine, carefully read this Operators Manual.
This Manual provides you with basic information on the safe operation of the D Motor engine. If any
sections of the Manual are not clearly understood or if you have any questions, please contact a D-
Motor International® authorized aircraft engines Dealer/Distributors or their Independent Service
Center. D-Motor International wants to ensure your satisfaction, flying your aircraft powered by this
D-Motor®-aircraft engine.

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SAFETY
INFORMATION
! WARNING : Never operate the aircraft equipped with a D-Motor at locations, airspeeds,
altitudes, Or other circumstances from which a succesful no-power landing cannot
be made, after sudden engine failure (stoppage).
•The D-Motor engine is not suitable for acrobatics.
•The selection and use of the D-Motor on any aircraft is at the sole discretion and
responsibility of the aircraft manufacturer, assembler and owner or user.
•Duet o different designs, equipment and types of aircraft, D-Motor will allow no warranty or
representation on the suitability of its engine’s use on any particular aircraft. Furthermore,
D-Motor grants NO warranty or representation of its engine’s suitability with any other part,
component or system which may be selected by the aircraft manufacturer, assembler or user
for aircraft application.
•Whether you are a certified pilot or a student, complete knowledge of the aircraft, its
controls and operation is mandatory before flying solo. Flying any type of aircraft involves a
certain risk! As user or owner of a D-Motor engine, be informed and prepared for any
situation or hazard associated with flying.
•Make sure that you also obtain as much information as possible about your aircraft and
engine (Service and Information Bulletins), their maintenance and operation from your
dealer!
•Be aware that our engines may seize or stall at any time! This could lead to crash landing and
possible severe injury or death. D-Motor recomments strict compliance with the
maintenance and operation and any other information which may be given to you by your
dealer or was published on the D-Motor website (https://www.d-motor.eu)
•Fly only when and where conditions, topography, and airspeeds are the safest !
•Use proper aircraft instrumentation. D-Motor does not deliver this instrumentation!
•Always ensure BEFORE FLIGHT that all engine controls are operative. Make sure that all
control scan be reached in case of an emergency.
•Always run the engine and propellors in a bystander clear area !
•DO NOT leave the aircraft unattended with the D-Motor engine running !
•Keep a engine LOGBOOK and respect the engine and aircraft maintenance windows. KEEP
YOUR D-MOTOR ENGINE IN TOP OPERATING CONDITIONS AT ALL TIMES.