WEICHAI WD10 Service Manual - Common Faults
Service Manual for WD10 Diesel Engine
21
3 Diagnosis and Troubleshooting of Diesel Engine
Common Faults
WD10 China II series diesel engine is designed and manufactured under strict quality guarantee
system, each delivered engine has passed specified tests. Since diesel engine is precision machinery,
guarantee for long-term reliable service is inseparable from correct maintenance. Causes for diesel
engine early failure are as follows:
Violation of operating regulations, poor management and improper applications;
Fail to maintain the machine according to requirements or even no maintenance;
Ill manufactured accessories, fake and inferior accessories will greatly shorten the life of
engine.
Unsuitable or unqualified fuel and lubricating oil brand.
31 Diagnostic Methods
Common diagnostic methods for diesel engine failure:
Observation method: Check the exhaust gas color for fault diagnosis (Fig. 3-1).
Auscultatory method: Determine the location, type and degree of the trouble according the
abnormal noise produced by the engine (Fig. 3-2).
Fig. 3-1 Observation method
Fig. 3-2 Auscultatory method
Single cylinder deactivation method: Deactivate a certain cylinder to determine whether the
trouble is caused by this cylinder. The general way to deactivate a suspicious cylinder to stop
its fuel supply, by comparing the engine state changes, the serviceman can further search the
trouble location or narrow down cause area.
Comparison method: For some assemblies or parts, check whether they are in failure by
replacing them.