Casement window operator

I need the screw part of the crank for a casement window. The window is on the right from inside, but there is an L on the right arm of the mechanism. I can crank the window open, but when I crank it to close, it stops an inch or two short of fully closed. The last thread of the crank screw is worn down because the window isn't aligned properly, I suppose. Can I just replace the screw cartridge, or do I have to get the whole operator? I'll be leaving here at 10 AM tomorrow, and won't be back until late afternoon. I will be here pretty much all day Fri. I will supply pictures, ser. #s, and measurements if needed.

Thanks,
Tom

Paul,

Thanks for the reply.

You don't need measurements, or anything?

Tom S