About 10 feet of 3/16" or 1/4" nylon rope is all you need. Roll the piston to the bottom of the stroke, cram as much rope through the spark plug hole as possible, then squeeze it tight against the valves by turning the crankshaft. No air needed, and no way to drop a valve into the cylinder. Obviously, leave a little rope hanging out!

Here's the spring tool you need:

http://www.tooltopia.com/_img/KDT/KDT2078.jpg

K-D Tools and several other manufacturers sell similar items.

Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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