Moteurs Baudouin 12M26 Series, Operation & Maintenance Manual

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Operation & Maintenance Manual for 12M26 Series Gas Engine
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Chapter 5 Analysis and Removal of Common Faults
12M26 Series natural gas engines are designed and manufactured in compliance with a strict
quality assurance system. Each engine leaving our factory is tested as specified. In addition,
natural gas engine is a kind of precision machinery. Its long-term performance guarantee is
inseparable from the normal maintenance. Usually the following causes may lead to the early
failure of an engine:
◆
Unprofessional operation and poor management and operation;
◆
The engine has not been maintained or repaired as per schedule or even has been repaired
instead of being maintained;
◆
The accessory quality is poor; especially the counterfeit and shoddy products will shorten
the service life of an engine greatly;
◆
The grade of lubricating oil is improper or disqualified.
5.1Diagnostic method
The common faults diagnostic methods of natural gas engine include:
◆
Observational method: Determine the fault by observing the fault characteristics such as
smoke exhaust from engine;
◆
Listening method: Determine the nature and degree of faulty parts by listening to the
abnormal sound from the engine;
◆
Cylinder disconnection method: Stop one cylinder and determine whether this cylinder is
in fault. Usually the maintenance personnel stop supplying natural gas to the targeted
cylinder and compare the changes in engine state before and after that in order to further
find out the faulty parts and cause, or to narrow down the range;
◆
Comparison method: the maintenance personnel replace some assemblies or parts to
determine whether they are in fault.
Note:
①
The causes for engine faults shall be determined carefully. Do not disassemble the engine
arbitrarily before figuring out the causes; otherwise, the fault cannot be removed and a
more serious fault may be further caused due to improper reassembly after disassembly.
②
Please send the key parts such as ECU, electronic throttle valve and turbocharger to the
maintenance stations appointed by Weichai for maintenance and inspection.
5.4 Common faults and trouble removal