Re: Oil level too high?
1/4" of oil will have nothing to do with a runaway engine. The oil level has to get high enough (typically several inches) to get sucked up past the piston rings, in order to be combusted. 1/4" of extra oil may contact the camshaft bearings, may cause a little foaming, but there's no way it will cause a runaway engine.
And given normal engine tolerances, and the extra leeway added for marine diesels operating at all angles and motions, the odds are 1/4" of oil will harm nothing.
Don't panic with thoughts of runaway engines, ain't gonna happen from this.