“We are currently experiencing an issue with Genset-xxx whereby lub-oil is being observed in the HT Expansion and Maintenance-water tanks. We have replaced the HT-water pump (engine-driven) with an overhauled unit; we are yet to open the removed pump for inspection. Can you please assist with appropriate advice and also a cross-section drawing of the engine-block illustrating the passages/channels for lubricating-oil and HT-water.” We have advised them to check the pump seals for the removed pump and the lube oil cooler for leakages although this last option would have higher downtime and we suggested it as a last resort.We would like to seek solutions further to this
I would be more inclined to go with a leaking oil cooler as a source of contaminated water. The water pump should not allow mixing of liquids across the oil seal if the tell-tale hole is not blocked, an unusual combination.
My thoughts are like wise; oil contamination via the cooling water pump is unlikely, there is a strict separation between both fluids. For the engine block we only have the main gallery casted in, and this has enough separation with the liner spaces. I would also point towards the LO cooler. I recommend to skim the oil form the expansion and maintenance water tanks in order to see the amount of leakage. The engine has been recently overhauled if I am not mistaken and I may be possible that oil spils in side cylinder heads, block, piping, etc. is causing the film of oil on the water.