2005 15hp tiller kill switch/button very stiff

[MichaelAngelo1]

Picked this up off of classifieds. The red button on the center of the tiller handle needs a lot of pressure to kill the engine. I know this button is an issue on older outboards - i have a 1990 15hp that the red buton doesn't even do anything. Any idea how I can fix this stiff button?