I've seen several instances (3 or 4) where an engine refused to run with new plugs after ONE incident of serious flooding. Fired right up with nothing but a plug change in each situation! It seems that an invisible coating of conductive material of some sort coats the porcelain insulators and allows the voltage to leak away down the surface of the insulator without jumping the plug gap. I've also salvaged seriously fuel fouled plugs by lining them up on a piece of steel and heating the tips red hot with an acetylene torch.
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
Love your enemies and drive 'em nuts!