Due to a sequence of mishaps my transom shower emptied my water tank into the bilge. The bilge pump came on and (I assume) shifted most of it but there is now about 3 inches under the engines. The company I bought the boat from say that the bilge pump is not allowed to be configured so that it pumps out the water from under the engines. Something to with engine oil being in it and not wanting that put in to the sea.

Firstly, is that correct?

Secondly, how do I get it out? It is clean water, no oil in it.

Is it important to get it out or can I just leave it in there?