What you’ll need: screwdriver, trim pry bar, soft wire brush, grease and oil solvent, replacement crank, household oil, white grease, paper towels
1) Open the window and disengage the arm from the track. In some models this will require that you remove the screws first.
2) Remove the mounting screws that hold the hardware to the window.
3) If you can’t see any visible screws, remove the handle by listening the set screw holding onto the shaft. Lift off the snap on plastic cover to find the screws.
4] If you don’t have this kind of cover, use a trim pry bar to remove the trim that goes from side to side and is notched around the gearbox. You may or may not find nails here.
5) Clean the gearbox with the wire brush and the solvent.
6) Operate the mechanism to make sure the gears mesh properly. If you need a replacement, contact your window manufacturer. If you look carefully at the metal spacer between the panes you’ll probably find the manufacturer named there. Or bring the old part with you to the hardware store when you go to buy a replacement.
7) Working from the outside, clean the track on the sash’s underside with a wire brush and solvent. You need to remove old grease that is built up in there.
8) Lubricate the window operator with some household oil and reinstall it. Just reverse the removal procedures and steps 1 through 4.
9) Lubricate the track on the sash’s underside with white grease.
10) Reattach the arm to the sash and operate the window crank.
11) white any excess grease off the track with paper towels.