- Fri Jan 23, 2015 9:05 am
#43701
Regarding crankcase fumes exploding, when I worked as a marine engineer, the big diesels had 'crankcase explosion doors' fitted to the sides of the crankcases, these manholes usually having a large diameter spring loaded disc in them - a sort of relief valve - for if an explosion occurred also served as access doors for if you needed to go in and check or change big end or main bearing shells. I never saw a crankcase explosion happen but was told that it was not pleasant to witness. With these large engines holding so much oil, about 6 to 8 x 45 gallon drums for one engine's oil change, we used to send samples back to the manufacturer every so often [in our case Castrol] and they would test it for all manner of degradation and impurities. One critical test was of the closed flashpoint, or the temperature at which the oil could ignite inside the engine. If it was below 200 c, it was time to get it out, as there was a good chance a crankcase explosion could occur.
