About 5 years ago I bought a sweet running 235 that I pulled from a 55 first series pickup. Owner wanted V/8 power. I drained the radiator and discarded hoses when I pulled it but did not drain the block hoping that It had antifreeze in it. I pulled the spark plugs and squirted in a lot of mystery oil for storage. About 4 years later I tried to turn over the motor with the fan blade and found it to be stuck. I remove the starter an broke it loose with a crow bar. It wasn't stuck too tight, but after about one revolution, It belched out of cylinder #1 about a cup of water, followed by the mystery oil that was underneath. Question is: Should I even consider rebuilding this engine or even pulling the head to check out the damage. My neighbor suggested than the water left in the block might have breached a head gasket and I might get by with only a head gasket replacement. Hate to rebuild an engine that ran so good. Any opinions or experience with ice damage?