Unless it was a reverse drive in a twin engine boat, it is no problem, as most everything is the same as a passenger car engine. The problem with an old boat engine is, no antifreeze or corrosion inhibitors are used in cooling the engine as lake, river or ocean water is used to cool the engine and sometimes there is a great deal of rust inside the engine water passages. Sometimes the corrosion is so bad that the block is very thin in places.
