[Gregski]

years ago my buddy "Harley" Bill, picture a 6' 8" skinny Colonel Sanders from Tennessee showed me how to do a valve leak test on my '83 Shovelhead (that be a Harley Davidson for the uninitiated) using gasoline

now you could do this using water, but water molecules be bigger than gasoline, so you may need to leave the liquid in the chambers longer while you have dinner, or even overnight, where as gasoline, gives you an almost immediate feedback

so we fill the spark plug holes with [ahem] spark plugs, and flip them rascals upside down, and level them with a socket of approximate height

I like to put clean cardboard or a paper grocery bag underneath for better visability of any dripage or leakage

as you can see our old heads looked tight, if there was a problem with a valve sealing you would know right quick