Did you check that the fan is working? and that there are no leaks in any of the hoses? Any leak in the system will also cause cooling problems. A bubble in the cooling system will also prevent good system cooling. This could also be a leaky/cracked head.
Be careful when working in and around a hot engine, my mechanic got burned really bad when a hose burst while he was working under the hood of a British sports car.
Good rubber hoses should feel like the tread on a new tire if you stick your thumbnail into it. Stiff and the rubber rebounds quickly. Bad hoses feel crunchy and your finger nail won't rebound with a good force.