Window Crank Repair – How to Repair a Broken Window Crank

Crank windows can be a lot of fun to use, but they can also be a pain in the arse when they don’t open or close as they should. This can happen for a number of reasons, but one of the most common is a problem with your window crank.

The window crank is a simple mechanism that opens and closes the casement window sash. However, like many other mechanical devices, it can become dysfunctional over time.

If you have a window Window Crank Repair that isn’t functioning properly, the first thing you should do is take a closer look at the mechanism. This can help you determine if the crank handle is broken or if there is another problem.

For example, if the crank handle only spins when it’s turned or doesn’t pull in the sash far enough to engage the lock, the gears are probably stripped and you’ll need to replace the crank system.

Similarly, if the window crank doesn’t work at all, or the sash is stuck in place, the drive worm and gears are probably stripped. Fortunately, this type of repair is relatively easy and cheap.

1. Remove the crank operator and handle from the window (Photo 1).

If the teeth on the crank handle are worn or broken, it may be best to simply replace the entire handle. But if they are still fine and you want to keep the old crank handle, it’s easier to just replace the crank operator.

2. Disconnect the window arm from the guide track and move it until the plastic guide bushing aligns with the guide track notch.

3. Line up the new crank and screw holes, then reattach the window arm and the casement cover.

4. Test the crank to ensure it is working correctly and lubricate the mechanism as needed before reinstalling it.

5. Clean out any debris that has built up on the crank mechanism or on the sash.

If there are any spline marks on the crank mechanism, this is a good indicator that the spline has worn down or broken. It’s also a good idea to lubricate the spline and gears as recommended by your manufacturer.

6. Check the regulator track for hang-ups and make adjustments as necessary to fix it.

If your window crank isn’t working, it’s likely due to a malfunction with the regulator. A regulator is a small mechanism that triggers the pivot point of the window arm and moves the other arm connected to the window track, which is in turn what raises or lowers the sash.

The most common types of regulators are the parallelogram and the modern electric-driven cable systems. The former uses a crank gear to trigger the regulator’s pivot point and the latter uses an electric motor to raise or lower the window.

Either type can be problematic if the gears and other components are wearing down or have been exposed to the elements. Both systems will need a thorough cleaning and lubrication to get them running smoothly again. If you’re unsure about whether to do this yourself, reach out to a professional.