The house was built in 1966 and the windows in the living room are two sections, the ones at the bottom have hinges on each side at their top so they can be opened. At the bottom of the window a metal bar is normally folded sideways parallel to the window and in that position a cam or lever action helps keep the window sealed. By opening the bar 90 degrees, the bottom of the window opens a bit and then by unfolding and pushing on that bar, the bottom opens outward.

What is needed to replace that sticky obstinate bar system with a crank system?

I have pictures but each time I try and upload a message says they are invalid types. Hopefully someone understands the type of window hardware I am describing and can help otherwise I'll try and figure out how to get pictures posted