How to Repair a Faulty Window Crank

Don't put up with a struggle every time you open or close a casement window. Restoring it so it works like new is easy. Procrastinating may result in damage to the mechanism and the added cost of replacement parts.

  1. Open the window and, working from outside if necessary, disengage the arm from the track. In some models you must remove the screws that attach the arm to the sash.

  2. From inside, remove the mounting screws that secure the hardware to the window.

  3. If there are no visible screws, remove the handle by loosening the setscrew that holds it onto the shaft and lift off the snap-on plastic cover to access the screws.

  4. If there is no such cover, use a trim pry bar to remove the trim that extends from side to side and is notched around the gearbox (see Tips). There may or may not be nails.

  5. Clean the gearbox with a soft wire brush and a solvent such as kerosene.

  6. Operate the mechanism to make sure the gears mesh properly and aren't worn. If a replacement is required, contact the window manufacturer. Most windows do not have the manufacturer's name printed on the hardware or window, but if you look carefully at the metal spacer between the panes of an insulated unit, you'll probably find the name there. Or bring the old part to a window or lumber dealer who can identify and order it for you.

  7. Working from outside, clean the track on the sash's underside with the same brush and solvent to remove dirt-caked grease.

  8. Lubricate the window operator with a little light household oil and reinstall it, reversing the removal procedure in steps 1 through 4. Do the same if you are installing a replacement part.

  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. Wipe any excess grease off the track with paper towels.

  12. Tip

    To remove wood trim, first break any paint sealing the joints using the tip of a utility knife. This will make the piece easier to remove without damage. Work very carefully to avoid cutting into the wood or injuring yourself. If you don't want to reinstall the old part until a new one comes in, just push the window closed from outside, and have someone engage the sash lock from inside.


    Use caution if you must lean out a window or work on a ladder to disengage the arm and clean the track.