Over time window sash locks can stick and no longer work. Window sash locks are essentially a small hinge that slides and clamps to a small lip on the upper window. You can replace window sash locks but if you want to maintain the historical accuracy of the home and the window you are better off removing and repairing them. It is not a hard project to do and the article that follows will show you.
Remove Window Sash Locks
You can attempt to repair window sash locks with them still attached to the windows but this could potentially damage the window. It would also most likely be a temporary fix as the wood and paint on it can eventually warp or crack and jam the latch mechanism. Window sash locks are very easy to remove and all you will need is a tiny Philip’s head screwdriver and possibly the paint scraper. At the top of the lock, you will find several small screws. They hold the lock in place. Remove them from the lock and put them off to the side in a safe place to use them later. You can now lift the lock, up off of the window. In some cases, window sash locks are sometimes painted over. Use a putty knife and wedge it between the lock and window and begin prying it off the wood until it is removed.
Window Sash Repair
This is optional but is worth the time to keep window sash locks working properly. Use the paint scraper and scrape off all the paint where the lock will be installed. Wipe it off with a clean rag. Apply a small amount of wood putty over the area and then spread it out with the putty knife. Be careful to not get it all over the window. If you do this prior to repairing the lock the putty will be dry and you will not have to wait to install it.
Repair the Lock
Window sash locks are very simple which means easy to fix. Use the steel brush to remove any visible rust around the mechanism. Wipe it down often with the clean rag to remove the oil you leave behind from your fingers. Once all the rust has been removed you can then attach the straw attachment to the lubricant and spray the mechanism. Move it from side to side until it moves freely. This will remove rust and debris inside the lock. Wipe it down with a clean rag.
Replace the Lock
Sand the wood putty until it is flush with the window. Place the lock in place and then screw it down with the screws that you removed previously. Pour a little olive oil on a paper towel and buff the lock. Wipe it down with a clean rag to remove the oil.