auto choke on a single barrell

i think my auto choke is sticking,,,the flapper on the carb is not opening up at start.....how do i go about putting a manual choke on it?

its on a straight 6, 235 chevy

it has a singlke barrell, rochestor

 

Most Chevrolets have a 'divorced choke. That means the choke is away from the choke and located in the intake manifold . The older Chevrolets had internal chokes . You would notice those carburators .

To adjust the Divorced types, bend the rod to allow the flap to close. Heat , from the intake is what makes the bi-metal spring to expand causing the spring to pull the flap open. scrubba