Waukesha 7044 Gas Engine Failure Investigation

Abstract

Three engine failures occurred from March to July in 2015. The failures were due to engine overloading and in each of the three instances caused severe scuffs and cracking on pistons and liners, particularly on #4 cylinders. Operating condition changes were identified as the root cause for the recent engine overload failures. Several maintenance issues, such as incorrect stepper motor settings, lubrication oil over filling and failed spark, also contributed to the failures. These factors combined and caused the engines to be overloaded and triggered the failure mechanisms which lead to the engine failures. To avoid failures in the future, the recommendations are provided, such as reduce the engine load by increasing the compressor clearance; monitor the engine load when operating condition changes and provide appropriate engine load awareness training to engineering and field personnel.