If a bar on the crankshaft won't turn the motor, my guess would be the cylinders have rusted and stuck the Pistons. This is just assuming all was fine, then it went into storage, now it won't turn over. A bore scope is handy, but not required. Pull the plugs, put about 50-60cc of penetrating oil in cylinder and let it sit a couple days. Use the bar to wiggle the crank back and forth till it breaks loose. Good news is the 140 is a fairly inexpensive and sturdy engine.