No offense, but isn't the previous owner always confident that their terrible looking engine still runs, & that they were so meticulous, except that they let the cabin fill up with 2 feet of water? LOL. It is the job of the seller to highlight the good points, & ignore their neglect. That's how they sell it. I just hope you didn't pay too much, because that engine looks like its toast. Its not just where it was submerged to almost the top of the block. Remember that when water hits the battery cables it causes electrolysis & massive corrosion occurs to anything metal that touches this bath of electrolyte charged, corrosive water. It will cause zinc to leach out of bronze & porous weakening. I suspect that all of your thru hulls & valves have massive corrosion & should be replaced as a precaution against them breaking off & sinking your boat. From your pics it looks like all of your hoses & fittings are completely original on that engine. Hoses should be replaced about every 10 years, as they dry rot & if any of them fail, they can also sink your boat. The only part that looks like it was ever replaced was the water pump, which is now corroded from flooding. I don't want to discourage you, but I reiterate that you should hook up a good battery to the engine, but if it won't even turn over freely, the motor may be locked up from corrosion. Even if it does turn over, I would have no faith in it lasting any real length of time. Most of us who still have original engines have been rebuilt by now, & that motor shows every sign of massive corrosion & needs a rebuild, unless you want to take your chances out there. My 2 c.