As per the previous comment, if the Oil is Milky in color, you have water contamination. You need to identify where this water is coming from before running the Engine
. Is it sea water cooled or Heat Exchanger
? Possible cause may be Rear seal failure in the water pump
. Sorry don't know the Engine
If you have a leaky injector etc, then the oil level in the sump will increase, but you won't necessarily be able to see the fuel. The concern is why there is pressure in the sump?
<I had some pressure and oil and either fuel or water seemed to come out from the dipstick pipe.>
What is the Oil Level? not overfilled? Apart from checking if there is a blocked breather pipe, you may want to call your local man with the golden spanners to identify where this pressure is coming from