How a casement crank works
A casement window opens outward on hinges. When you turn the handle, it drives a small gear box called the crank operator. The operator moves an arm that pushes the sash open or pulls it closed. A problem with any of those parts can stop the window from working.
Match the symptom to the cause
- The handle spins freely: the splines inside the handle (or on the operator shaft) are stripped. Often just the handle needs replacing.
- The handle turns but the window doesn’t move, or it grinds or clicks: the gears inside the crank operator are worn or broken. The operator needs replacing.
- The window opens partway, then stops: the operator arm may have come out of its track, or the arm or operator is damaged.
- It’s very stiff to turn: dirt and old lubricant in the hinge tracks, or a sagging sash dragging on the frame.
- It won’t close tight or lock: worn hinges, a misaligned lock or keeper, or worn weatherstripping.
What to try first
- Open the window as far as it will go and look at the hinge tracks along the top and bottom. Vacuum out dirt and debris.
- Lightly spray the tracks and hinge pivots with silicone lubricant. Avoid grease or oil, which attract dirt.
- Check that the handle’s set screw (if it has one) is tight.
- Look for an arm that has slipped out of its track under the sash.
If the handle still spins or the operator grinds, the part is worn and needs replacing.
What repairs cost
| Repair | Installed price |
|---|---|
| Crank handle | $99 |
| Crank operator (gear box) | $249 |
| Lock or lock keeper | $99 |
| Casement hinges (pair) | $249 |
Hardware repairs include a $149 service call, which is credited toward the repair, so a single handle comes to $149. See window crank replacement for more.
Common questions
Can I replace a crank operator myself?
It’s possible, but operators come in many sizes, arm lengths and hand orientations, and the old one has to be matched closely. We bring the right part and install it in one visit.
Do I need a new window if the crank is broken?
No. Cranks, operators, locks and hinges can all be replaced on your existing window.
Why is my crank hard to turn only in winter?
Cold thickens old lubricant, and ice or frost can bind the sash. Don’t force it. Clean and lubricate the tracks with silicone once it warms up.
