- Thu Apr 27, 2017 2:49 pm
#67319
In a former life as a marine engineer, we used to send occasional oil samples from the big marine diesels away for analysis by the manufacturer, as there were several hundred gallons of oil in many of the engines and too much to just discard every so often, due to the expense. The results would come back with all sorts of info about how many parts per million of this, that and the other were found, but, interestingly, there would be an alert if the closed flashpoint had dropped below 200 deg C. This was because there was a possibility of the oil igniting inside the engine and causing a crankcase explosion and the oil should be changed if this was the case. There were even large, spring loaded one way valves on several of the engines' crankcase 'doors', the idea was these would relieve the pressure of a crankcase explosion without allowing any fresh air in to aggravate matters. It sounds like the above was a primary case explosion, probably caused by the heat and friction of the rotor rubbing the stator, or, possibly a spark from the stator, although I think this would be less likely. Regards, Paul.
