A window handle you have to force round is more than an annoyance: ignore the early signs and the whole hardware system suffers. There are three common causes: dust and dirt in the mechanism, lack of lubrication and a badly aligned sash. Less often the spring or the locking bar has worn out.
Start with cleaning and lubrication, then check the adjustment, and only replace worn parts if that does not help.
What you will need
Important: Cover the sill and frame with paper or a cloth before you start to avoid marks. Keep sprays off the glass.
Step 1
Remove the handle
Turn the cover plate at the base of the handle through 90 degrees to reveal two screws. Undo them and carefully pull out the handle with its spindle. This gives you access to the mechanism and shows where the sticking is: in the handle itself or in the gearbox inside the sash.
Step 2
Clean the mechanism
Brush dust, dirt and old lubricant out of the handle, its recess and the accessible hardware, paying attention to awkward corners. While you are at it, check the cam bolts, keeps round the sash and the seals: dirty or worn, they also add resistance.
Step 3
Free the sticking parts
Flip up the straw on WD-40 Smart Straw and apply it precisely to the spring, the square spindle and the gearbox opening, and to the moving locking parts along the sash edge. It creeps into gaps, loosens dirt and frees seized parts.
Turn the handle several times to work it in, then wipe off the excess.
Step 4
Apply a long-lasting lubricant
The multi-use product frees the mechanism quickly, but for a lasting result apply a more durable lubricant after cleaning. Put WD-40 Specialist White Lithium Grease on metal locking parts and the gearbox: it clings to vertical surfaces and does not wash off.
Treat the runners and seals with WD-40 Specialist Silicone, which cuts friction, does not collect dust and protects against moisture.
Step 5
Adjust the sash
If the handle tightens right at the end of its turn, the sash has often dropped so the cams no longer meet the keeps on the frame. Use a hex key on the bottom hinge screw to raise the sash and, if needed, ease the compression on the cam bolts. Check the handle after every half turn.
Step 6
Replace worn parts
If cleaning, lubrication and adjustment have not helped, or the handle will not spring back or has play in it, the spring is probably broken or the locking bar worn. Buy a handle or part from the same system, fit it with the spindle, tighten the screws and lubricate the mechanism before final assembly.
Tip: Handle spindles come in different lengths. Before buying a new handle, measure the old spindle and the profile depth so you get the right size.
What next
Service window hardware twice a year: in autumn before the cold and in spring when windows are opened often. In damp rooms such as bathrooms and kitchens, lubricate more often. The same WD-40 Smart Straw will also free door locks and hinges.
These uses come from the experience of WD-40 users in many countries. Always follow the instructions and warnings on the product label.
More guides in «How to use».