Here is another 216 story.
Well its actually from my 48 Chevy passenger car but it is basically the same engine.I got the car a little over 2 years ago.It was last registered in 1965 so the engine did not work for more as 40 years.A trader before me got the car from the original first owner.Without any other preparation he used a 12 volt battery in an attempt to start it. The result was 3 push rods bended and one rocker broke as a result of 4 solid valves.I manage to get the valves to move freely without dismantling the cylinder head, replaced the damaged parts, drained the oil (witch was as good as a black ice cream), filled with fresh oil fired the engine and it started in 10 seconds.I have driven some 550 miles up to date without any problem so far!
I think if someone takes good care of a 216 it will last for ever.
Jianis