60081 – ENGINE FAILURE INVESTIGATION

• ESG were assigned the task of investigating the failure with the intention of:
• Identifying the root cause of failure
• Assessing the potential for further failures in the same mode
• Making recommendations to mitigate the risk of further occurrences
• Providing a system of cost effective repair

Initial indications pointed towards failure of the large end bolts. Though the large end bolts had clearly failed in fatigue, they were not deficient in any way. The failure was found to have initiated at the large end bearing. This bearing failure had set up a condition where the bolt heads were being abnormally loaded.

The bearing failure was found to be due to deteriorated overlay, this was believed to have been due to a historic event, possibly due to water contamination and or poor oil films. The overlay material is believed to have overheated in the loaded region and suffered copper tin diffusion at the bonding layer and in the overlay.

The same effect has been observed on other engines, which were identified to have had internal coolant leaks.

Key Features

• Systematic investigation to understand initial mode of failure and sequence of events leading up to the failure
• Work closely with engine and bearing OEM’s to understand the mechanism and cause of bearing overlay deterioration.
• Understand the extent of damage to engine and locomotive and make recommendations for cost effective repair
• Use of Spectrographic Oil Analysis to Identify other ‘at risk’ engines
• Manage and control the measures and checks put in place to mitigate risk of further failures

• Hands on Investigation and Analysis (Inspection, Metallurgical, Geometric, Procedural)
• Dealing with both the Engine and Bearing Original Equipment Manufacturers (OEM)
• In Depth Knowledge of Diesel Engines
• Project Management
• Risk assessment
• Review and creation of technical documentation
• Technical liaison with OEM’s