Sticky locks are a common problem with older doors. A sticky lock is usually caused when excess dirt and grime binds up the mechanisms that enable the lock to turn smoothly. Once that happens, getting in and out of doors can be a major hassle. Fortunately, there are a number of ways to fix a stuck lock without calling in the professionals and breaking your budget.
1. Powdered Graphite
Powdered graphite is a dry lubricant that enables metal surfaces to move freely without attracting dirt, as traditional lubricants often do. Powdered graphite is a great option if the lock is so sticky that it almost traps the key, making it impossible to remove. You can find powdered graphite at your local hardware store for only a few bucks.
Start by cutting the tube of powdered graphite at an angle and covering the ground under the door with paper towels to catch extra graphite. Then press the opening of the tube in the lock. Ideally, the opening of the tube will be small enough to fit inside of the lock. With the tube firmly pressed against the lock, gently squeeze the powdered graphite inside. Only give it a couple of squeezes before trying the key. Repeat this process until the key operates properly. Be careful not use too much graphite at a time because the powder can stain nearby surfaces.
WD-40 is another way to free up a sticky lock. This handy lubricant is ideal if the lock is not too sticky and you can still move the key in and out without great force. In fact, in many instances, squirting some WD-40 inside the lock is all you need to fix the situation.
Start by connecting the red applicator straw over the spray can nozzle. The straw will increase the accuracy of the spray and enable you to get deep inside the lock. Spray the lock a few times and allow it a few minutes to work its magic. Then wiggle the key in the lock a few times. If the key is still difficult to move, spray the lock a few more times with the WD-40 until everything frees up.
Tips & Tricks
If the lock binds up the key and makes it impossible to remove, spray the lock with some WD-40 and wiggle it back and forth. The WD-40 should free up the key, though you might need to use a vise grip to pull it loose. If the key has completely broken off then you will need to buy a key extractor to get it free. Avoid using any kind of oil to lubricate the lock because this will only attract more dirt and grime in the future. Instead, lubricate the mechanisms with some graphite powder.
If none of these steps fixes the stuck lock, call your local locksmith and have them check it. In some cases, a loose pin can cause a stuck lock and replacing it is the only solution.