I just pulled the heads off my current engine to use on my new one. All the exhaust valves have a tan color except # 7 which has a white powdery look. The tops of all the pistons are the same no difference in color and not sure what causes this?

Bumped, one of you rocket scientist must have a clue.

Looks like you might have a lean running condition on that cylinder.


~DJ~ AKA "Bleach"
1956 Ford Fairlane Town Sedan 30K original miles

Thanks, thats what I thought but the rest of the combustion chamber, piston top and spark plugs look the same as the other cylinders. Not sure why one cylinder would run leaner, maybe an air leak on an intake gasket??