If your casement window operator has stopped functioning, it may be that the gears inside the handle have sheared. There are many different styles and types of casement window operators but for the purpose of this task we will concentrate on the ‘crank’ style, as this is the most common.
Step 1 – Stripping
You may have interior window flashing or trim that covers the crank workings of the window operator, so if you do, remove the flashing to get to the inside. Test the crank with pliers and examine the teeth on the crank. If they are worn out, unscrew any fittings that require it.
Step 2 – Guide Arm
Open the casement window as far as is possible and push down on the guide arm to release it from the window tracking mechanism. Dismantled the mounting screws and remove the two halves of the crank operator.
Step 3 – Replacing
You should buy an exact replica of the operator you are replacing. In some instances this will not be possible but get as close a match as you can. Place the new operator on exactly the same holes as the old one and screw down the mount. Attach the new guide arm and then fit the screws of the new operator to the window, following the old holes. Screw down and pull the new guide arm into place.