There's a slightly more accurate way to find TDC. Find an old spark plug, and knock the porcelain center out of it with a punch. Thread the steel shell with a 3/8X16 tap, and screw a 2" long bolt into it. Cut the bolt head off with a hacksaw, and round off the end to a ball shape.
Install the plug into the #1 cylinder, and carefully turn the engine over by hand until the piston stops against the bolt. Mark the damper under the pointer with a sharpie or a piece of chalk. Now, turn the engine backwards until it stops again. Mark this spot. Measure the distance between the two marks. Exactly halfway between the marks will be top dead center.
Don't forget to pull the stop plug out before you crank the engine with the starter!
Jerry
