Dry the head thoroughly.
Set the head with the exhaust ports up. and fill the exhaust chamber with brake clean, or mineral spirits, or carb cleaner or whatever. Some thin solvent.
Watch the valve area (combustion chamber side) for any signs of leakage past the valves.
Leave it overnight, 90 percent of the liquid should still be there, and no signs of wetness past the valves.
If the exhaust pass, repeat for the intake valves.
If the valves pass, inspect the headgasket again for any signs it had failed and was no holding compression. If that is good, then suspect the piston.
pull the engine, the seperator plate, and then pull the wrist pin and piston for #3.
Edited by Gloyale, 25 August 2013 - 06:14 PM.