Mercury 7.5 hp no start

[Michawilden]

I have a problem with a 7.5 hp mercury. It has strong spark and strong compression but does however not start. Carb is clean. When i put Some fresh gasoline in the carbthroat it does not start up. Not even a small puff. Putting gas in the cylinder also results in nothing. Checked the flywheel key and the trigger. Both are good. Is it possible that the ignition sparks on the outside and nog in the inside? Or that the powerpack sparks at the wrong timing? The sparkplug also don't Seem to get very wet.
This engine has layed still for ten years or so. I do not have any known history

 

[tpenfield]

Could be that the plugs are bad or the reed valves are stuck or cracked

 

[Michawilden]

I thought of the stuck reeds, when the carb is removed, i can touch the lower reeds with a small screwdriver. These open and close and seem to look fine. I can not see the upper reeds but will try to look with a mirror. I pulled a couple of times and quite some air came out of the carb manifold so this might just be the problem.