Q: I have a lock that seems frozen. The key won’t turn.
A: First, are you sure you are using the right key? Many keys look alike and you wouldn’t believe how many times someone comes to us thinking the padlock or trailer lock is broken or defective, only to find out that they are using the wrong key. It seems simple, but does the name on the key match the name on the lock? I’ve seen customers using a Trimax key in a Diversi-Tech lock and can’t figure out why it won’t work.
If you look carefully at the cylinder as you turn the key and the cylinder turns, even slightly, the problem is not the cylinder. You either have the wrong key (yes, even with the wrong key, the cylinder can usually be seen to move slightly), or it is the internal mechanism of the lock.
Okay, so if you are sure you have the right key and the cylinder moves slightly. I would first lightly lubricate the cylinder with a Teflon product or just a drop of light oil. If it is a padlock, I would then see if the shackle has any wiggle in it. If it is frozen solid, you can sometimes tap on it gently with a hammer and break it free. I would then put a penetrating oil like WD-40 or Liquid Wrench in around every opening (shackle holes, cylinder hole, etc.) to reach the inner workings.
I have also read that pouring diet soda into a lock will help break a rusty lock (or bolt) free, but I have never personally tried it.
BE PATIENT!! Whichever method you chose, it took time for the lock to rust up and it may take time for the penetrant to work.
ALSO, don’t be tempted to put a pair of pliers on the key and try to force it. Keys aren’t really very strong and you will usually break the key before you force the lock open. (If you break the key off, see my tip on Broken Keys.) Keep tapping on the shackle, wiggling the key and adding more penetrant. If the lock is loose, you might even want to soak it.
FINALLY, after you get the lock open you need to lubricate it well. Many penetrants, including WD-40 will actually flush out the lubricants put in at the factory and you MUST replace them. As I have said many time, my preference is a tiny squirt of a Teflon product (such as the Master Lock lubricants we sell at Heartland Lock) in the keyway and a light oil (like 3-in-One) into the any place I can find where it will reach the internal mechanism.
If you have specific questions, please feel free to send me an email.
Feel free to attach pictures if you think it will help!