cant get automatic choke to work on

I have an older snapper riding mower, i just cleaned the carb. Now my problem is the automatic choke lever on the engine just wont pull the choke cable on the carb. I adjusted the throttle as far as it would go and still wont grab it. I tried bending the rod so it would be shorter, still the lever wont get it. I have a 491590 carb. If anyone has any idea how i can make it work that would help thanks.