On the approach to Bristol Temple Meads, 50044 shutdown after releasing some oil vapour. Initial observations were that the engine lubricating oil was very hot and the oil pump was struggling to keep the system pressurised. C50A technical staff present at the time were able to re-start the loco, and with assistance from 66720, the train proceeded forward into the station.
Initial investigations undertaken at Kidderminster found metallic debris in the coarse engine oil strainer; further work revealed that the oil cooling system was not fully functioning. These findings potentially suggested that a significant power unit failure was imminent, and more detailed investigation was needed to properly understand the fault. Consequently an oil sample was taken for detailed analysis in accordance with our standard maintenance and faultfinding practices. The results of the analysis revealed high metal content, the proportions of the different metals present indicating a bearing fault and potentially damage to other components.
Over the last few weeks a more detailed engine examination has been undertaken. This has revealed significant play in the B3 cylinder con-rod / crank shaft interface. A strip down of the big end bearing, has confirmed that this bearing has failed, and this In turn this has caused some damage to the crankshaft journal itself.
To repair this fault the power-unit needs to be removed from the locomotive, as all options for effecting a repair require more space than is available inside the confined engine room.
The Alliance are also planning to overhaul the oil coolant system and replace the coolant control system electronics (CU4 and CU5) with the same technology that has been developed by the group and successfully trialled over the last year on 50035 Ark Royal.
To remain on the mainline, 50044 now requires the new railway telephone system (GSM-R) to be fitted....
