Moteurs Baudouin 12M26 Series Manual

12M26 Series Gas Engine
Operation & Maintenance Manual

Operation & Maintenance Manual for 12M26 Series Gas Engine
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Foreword
12M26 series natural gas engine for power generation is made by improving the
previous Baudouin M26 series engine for power generation through removing of engine
fuel system and adding of gas supply system and relevant devices. This natural gas
engine is characterized by compact structure, reliable operation, excellent technical
performances in reliability, power, economical efficiency and exhaust emission, quick
start-up, easy operation and least maintenance, etc. It has already become a new power
source of power generation equipment and is frequently used as a main or standby power
source in coal mine, oil field, farm, gas station and other places. In addition, it can be
fueled by natural gas, methane and biomass gas, etc.
This manual briefly introduces the technical parameters, performance indicators,
structural features and usage & maintenance precautions of 12M26 series natural gas
generator.
The user shall comply with various specifications stipulated in this manual when
using this natural gas engine.If this manual was complied by users, it can extend service
life of the gas engine.
As the product structure is improving as the product develops continuously, this
operating manual may lag behind such improvement. The user (or retailer) can also
access http://www.weichai.com for information of latest products.
January, 2018

Operation & Maintenance Manual for 12M26 Series Gas Engine
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Dear customers,
Welcome to use Weichai products! Thanks for your love to Weichai products!
Please read carefully the operation & maintenance manual of the natural gas engine and operate it in strict
accordance with relevant specifications so that you can operate and maintain it properly.
Service commitment:
If the engine fails, please contact Weichai Call Center at 400-6183066 as soon as possible. Our company promises
that the authorized service center will arrive at the site within 3 h (the city where you locate), within 24 h (general
areas) and within 48 h (remote areas), and will provide fast, high-quality and considerate service according to
Weichai service specifications.
Please read the followings carefully before your use for the purpose of running the engine effectively.
●The natural gas engine has been tested in strict accordance with the test specification before its delivery. Do
not adjust ECU data or increase the engine power without permission. Otherwise, the company's warranty
service will become invalid.
●Turbocharger rotor shaft is a precision high-speed rotating component, which shall not be dissembled or
collided; otherwise, the company's warranty service will become invalid.
●The engine’s main bearing bolts and connecting rod bolts have strict torque and corner requirements, and
shall not be loosened or dissembled by user. Connecting rod bolts for one-time use of bolts, shall not be
reused; otherwise, the company's warranty service will become invalid.
●The engine shall always be filled with oil of grade specified in this Manual. It is recommended to use the
special oil for Weichai gas engine and filter the oil with a special cleaning filter. Each time the engine is
started, make sure to check whether the filling amount of coolant and oil is proper. Make sure that the engine
uses the natural gas for automobiles as specified in the national standard.
●Never run the engine without an air filter.
●A new engine must be subject to running-in for 50 h before being put into service.
●Each time the spark plug is replaced, tighten them to the specified torque and ensure the ceramic body is
clean.
●If the ambient temperature is likely to be below 0 °C and no coolant containing antifreeze additive is used in
the engine after parking, the coolant shall be completely drained from the water tank and engine.
●The electrical system components must be inspected and maintained by electrical technicians only.
●The electronically controlled system components must be inspected and maintained by professionals from
Weichai authorized service station only.
●After starting a cold engine, never run it at an idle speed for a long time; do not stop the engine immediately
after running under heavy load (except under special circumstances); instead, run it at a low speed for 5~10
min before parking.
●Before starting a new engine, check the gas pipe, gas supply device and electrical system. Pay special
attention to checking whether the electrical connection is loosened and the high-voltage coil is connected
incorrectly.
●If the engine cannot be started after three successive attempts, check the gas system and the circuit carefully
again.
●The engine has been sealed to prevent rust and corrosion before its delivery. Generally, the sealing period is
one year. The engine beyond the sealing period should be checked and necessary remedies should be taken.
●For inspection and maintenance, please go to the service station designated by Weichai. Spare parts
designated by Weichai must be used for maintenance. Weichai will not be responsible for any damage to the
engine caused by using the undesignated spare parts.
●Replace emission-related key parts (such as turbocharger, ECU, and pressure reducer) with those of the same

Operation & Maintenance Manual for 12M26 Series Gas Engine
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make and model as original ones; otherwise, Weichai will not be responsible for any consequences.

Operation & Maintenance Manual for 12M26 Series Gas Engine
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Instruction of the installation
1) This natural gas engine has undergone factory inspection according to the test specifications in a
strict way. Do not adjust any ECU data or increase the power of natural gas engine arbitrarily;
otherwise, all warranty commitments of our company will become invalid. As there are strict
requirements for torque and angle of rotation of main bearing bolt and connecting rod bolt of a
natural gas engine, the user shall not unscrew or disassemble the bolts. As connecting rod bolts
are disposable, they shall not be reused; otherwise, all warranty commitments of our company
will become invalid.
2) As rotor shaft of turbocharger is a precision high-speed rotating component, disassembling or
collision is strictly prohibited.
3) The natural gas engine is prohibited to work without air filter which could prevent particulates
from entering the cylinder.
4) Before operating a natural gas engine, the operator must read this operation and maintenance
manual carefully and follow the operation and maintenance procedures specified in this manual
in a strict way.
5) For the new natural gas engine, 50h running-in is needed, with maximum load not more than 80%
of the rated load and average load not more than 60%.
6) The operator must check whether the amounts of coolant and engine oil in an engine meet the
requirements before starting the engine every time.
7) Before starting the engine, switch to pre-lubrication position and pull the handle back and forth
to supply oil to the engine bearing, bearing bush and several other friction pairs and discharge
the air inside the oil pump to realize rapid lubrication after engine startup. This operation may
reduce friction, extend service life of the engine and achieve smooth startup of diesel engine.
8) After starting the engine, idle for 5-10minutes before adding part of load. Only when the water
temperature is above 60℃;After engine running with heavy load, do not immediately stop it. It
is necessary to idle running for 5-10 min at low speed.
9) If the engine would closed for long time, shutdown the gas is necessary.
10) If the working environment temperature may be lower than 0℃after shutdown but there is no
antifreeze additive in coolant, the coolant in water tank and engine shall be drained off.
11) The oil should be filtrated through the strainer before added.
12) The gas should filtrated throught filtration system.
13) The inspection of electrical system should be done by the personnel mastering electrical
knowledge.
14) The invalid duration of oil sealing of natural gas engine is one year. If they expire, please take
necessary supplement measures.
15) Our company perform the quality-trace filing for industrial power 12M26.

Operation & Maintenance Manual for 12M26 Series Gas Engine
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Operation & Maintenance Manual for 12M26 Series Gas Engine
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Before maintenance and repair, please notice that:
◆Avoid repeated exposure to used oil for a long time.
◆If possible, wear protective clothing and waterproof gloves.
◆Do not keep oil-soaked rags in the pocket.
◆Prevent oil from soaking the clothes, especially underwear.
◆Wash the uniform frequently. Throw away the oil-soaked clothes and shoes that cannot be
cleaned.
◆Use first aid immediately if there are any cuts or other injuries.
◆Apply protective cream before working so that the mineral oil is easier to get cleaned after
getting on the skin.
◆Clean your hands with soap and hot water, or use the hand sanitizer and nail brush to remove
all oil. If there’s skin natural sebum loss during the wash, products containing lanolin can be used to
help moisturize the skin.
◆Do not use gasoline, kerosene, fuel oil, thinner or other solvents to clean the skin.
◆If you have a skin irritation, consult a doctor immediately.
◆If possible, remove the oil/grease on the parts before handling them.
◆If there is possible danger to your eyes, use goggles or face shield. Eye wash solution must be
available around the operating location.
◆When maintaining the engine, do not splash oil or other liquids onto the floor. If there’s an
accidental release of hydrocarbons or other liquids, take all necessary measures to isolate the
leaking area to keep the environment clean and to protect personnel from injury.
◆The handling, storage and recycling of hydrocarbons, ethylene, glycol and petroleum must
comply with safety and environmental standards of the country where the operation is done.

Operation & Maintenance Manual for 12M26 Series Gas Engine
Content
FOREWORD ..............................................................................................................................................................1
INSTRUCTION OF THE INSTALLATION............................................................................................................................4
CHAPTER 1 STRUCTURE AND PROPERTY OF THE ENGINE.........................................................................1
1.1Model Meaning of M26 series industrial engine ................................................................................................... 1
1.2 Size of M26 series industrial engine ..................................................................................................................... 1
1.3 Main uses of M26 series industrial engine............................................................................................................ 6
1.4 Basic parameters of M26 series natural gas engine .............................................................................................. 6
1.5Schematic diagram of 12M26 series natural gas engine ........................................................................................ 8
CHAPTER 2 NATURAL GAS ENGINE CONTROL SYSTEM................................................................................................12
2.1 Schematic diagram of natural gas control system ............................................................................................... 12
2.2 Engine control system main parts technical requirements and installation requirements ................................... 14
2.1.16 Starter ............................................................................................................................................................ 21
2.3Communication interface of Gas engine.............................................................................................................. 22
CHAPTER 3 INSTALLATION AND USE OF THE ENGINE ...............................................................................................26
3.1 Engine unpacking................................................................................................................................................ 26
3.2 Engine lifting ...................................................................................................................................................... 26
3.3 Installation of the natural gas engine .................................................................................................................. 27
3.4 Preparations before starting the engine ............................................................................................................... 28
3.5 Engine starting .................................................................................................................................................... 29
3.6 Engine operating ................................................................................................................................................. 29
3.7 Engine shut-down ............................................................................................................................................... 30
3.8 Power Definition and Operation Conditions of natural gas Engine for Power Generation................................. 30
3.9 Environmental conditions ................................................................................................................................... 31
CHAPTER 4 12M26 SERIES GAS GENERATORS MAINTENANCE ....................................................................................32
4.1 Fuel, Lubricating Oil ,Coolant and Auxiliary materials ...................................................................................... 32
4.2 Routine maintenance of the gas generator .......................................................................................................... 35
4.3 Regular maintenance of the engine ..................................................................................................................... 37
4.4 Notice for Using the New Gas generator ............................................................................................................ 40
4.5 Gas generator for long-term storage of maintenance .......................................................................................... 41
4.6 Operation and maintenance specifications for main accessories of gas engines................................................. 42
CHAPTER 5 ANALYSIS AND REMOVAL OF COMMON FAULTS.......................................................................................47
5.1Diagnostic method ............................................................................................................................................... 47
5.4 Common faults and trouble removal................................................................................................................... 47
APPENDIX 1 RECOMMENDED TORQUE FOR MAIN BEARING BOLTS OF 12M26 SERIES ............................................50
APPENDIX 4 Q/WCQTG0007 “SPECIFICATION OF SPARK PLUG REMOVAL AND REFITTING OF WEICHAI NATURAL
GAS ENGINE” .............................................................................................................................................................54

Operation & Maintenance Manual for 12M26 Series Gas Engine
I. Scope ......................................................................................................................................................................... 54
II. Normative references ............................................................................................................................................... 54
III. Requirements and steps for removal and refitting of spark plug............................................................................. 54
APPENDIX 3 CORRECTION COEFFICIENT OF POWER OF ENGINE ..............................................................................60
APPENDIX 4 CORRECTION COEFFICIENT OF POWER OF ENGINE ..............................................................................60
CONTACT US...............................................................................................................................................................14

Operation & Maintenance Manual for 12M26 Series Gas Engine
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Chapter 1 Structure and property of the engine
1.1Model Meaning of M26 series industrial engine
Model Meaning of M26 engine：
1.2 Size of M26 series industrial engine
Size of M26 series industrial engine , See Fig 1-1、1-2、1-3、1-4 for reference.
XM26
XXX
EX
XX
X
D
Model (varity)
Emission level
Overload Power(kW)
Electricity generation
Product Series

Operation & Maintenance Manual for 12M26 Series Gas Engine
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Fig1-1 Outside drawing of 12M26 natural gas engine

Operation & Maintenance Manual for 12M26 Series Gas Engine
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Fig1-2 Outside drawing of 12M26 natural gas engine

Operation & Maintenance Manual for 12M26 Series Gas Engine
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Fig1-3 Outside drawing of 12M26 natural gas engine

Operation & Maintenance Manual for 12M26 Series Gas Engine
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Fig1-4 Outside drawing of 12M26 natural gas engine

Operation & Maintenance Manual for 12M26 Series Gas Engine
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1.3 Main uses of M26 series industrial engine
M26 series industrial engine was widely used in electric power equipment, pump power,
compressor power, oil and other industries, but Cross-industry application is prohibited.
1.4 Basic parameters of M26 series natural gas engine
Main technical parameters of 12M26 natural gas engine, see table 1-1、table 1-2、table1-3
for reference.
Table 1-1 Main technical parameters of 12M26 natural gas engine
Type
V-type、12cylinders、Four-stroke、Sparking plug ignition、
Turbocharging and intercooling
Cylinder diameter/stroke (mm)
150/150
Displacement (L)
31.8
Compression ratio
11.5
Ignition sequence
A1-B2-A5-B4-A3-B1-A6-B5-A2-B3-A4-B6
Cold state air valve gap (mm)
Inlet valve：0.3±0.03
exhaust valve：0.4±0.03
Valve timing
(Air valve gap:Inlet valve 0.3 ;Exhaust valve
0.4)
Inlet valve is open: 34° before TDC;
Inlet valve is closed: 40° after BDC;
Exhaust valve is open: 70° before BDC;
Exhaust valve is closed: 34°after TDC.
Starting mode
Electric starting
Lubrication method
Force-feed lubrication
Air intake type
Turbocharged and intercooled
lubricating oil capacity（L）
113
Cooling mode
Forced circulation water-cooling
Engine oil pressure (kPa)
450～650 (absolute value)
Crankshaft rotation direction (seeing from
free end)
Clockwise
Size（mm）
Long
2663
Wide
1524
High
1756
Weight(kg)
3240

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Table 1-2 Main performance parameters of 12M26 natural gas engine
Category
Unit
12M26 natural gas engine
Engine model
12M26
12M26D605E300NG
12M26D660E301NG
Type
—
V-engine, 4-stroke water-cooling, wet sleeve, Venturi mixture,
closed-loop control, sparking plug ignition
Number of cylinder
—
12
Valve per cylinder
—
4
Speed
r/min
1500
1800
Rated power
kW
550
605
Overload power
kW
605
660
Table 1-3 Tightening torque of main bolts and nuts
Bolt name
Bolt
specification
Tightening torque (N•m)+Re-twist angle (°)
Allowable
number of
repetition
Spark plug
M14×1.25
（25～28） N•m
Oxygen sensor
M18×1.5
（50±5） N•m
Water temperature sensor
M12×1.5
（25±5） N•m
①The corresponding requirements are posed on the strength grade of bolts and nuts used on the different
parts of the engine, and bolts and nuts of the same specifications but different strength grades may not be
mistaken or exchanged. The allowable number of repetition may not be exceeded. Otherwise serious
consequences may occur.
②Other torque of main bolts was seen in appendix 1.

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1.5 Schematic diagram of 12M26 series natural gas engine
1. Fan; 2. Pre-supplying oil pump; 3. Ingnition coil; 4.Oxygen sensor; 5. Exhaust pipe;
6.Turbocharger; 7.EFR; 8. Air filter; 9.Starting motor; 10. Oil filler and dipstick; 11.Oil
cooler; 12.Oil filter; 13.Cooling water inlet; 14.Electronic throttle

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1.Belt pulley；2. Gas inlet

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1. Engine support bracket；2. Flywheel housing；3. Flywheel

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1. ECU；2. Oil pan；3. Engine support bracket