Engines get hard to turn, or lock up entirely because the piston rings rust to the cylinder walls. Pull the spark plugs and pour 3-4 ounces of KROIL (www.kanolabs.com) into the cylinders. Wait about a week, pull the oil pan plug, and most of what you poured into the cylinders can be drained out and put back into the plug holes again. After a few cycles of fill/drain/refill, use the chisel end of a shepherd's crook wrecking bar or some other type of long pry bar between the flywheel teeth and the bellhousing to turn the crankshaft a little. Repeat the soak/drain/soak cycle, and keep turning the flywheel a little at a time. Eventually you'll get the engine to make a full turn. It's also a good idea to remove the rocker arm assembly and pushrods so sticky valves can be dealt with at a later date.

There's about a 50/50 chance you'll be able to get the engine running without a complete teardown and overhaul, depending on how deep the rust pits in the cylinders are.
Jerry

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