How to Reset a 178 Master Lock

eHow may earn compensation through affiliate links in this story. Learn more about our affiliate and product review process here.
A 178 Master Lock can secure gates.

Use the 178 Master Lock padlock to secure toolboxes, cable boxes, storage lockers, tool chests and utility meters. The curved metal bar that opens and closes is the shackle. The 178 Master Lock padlock has a 1-inch stainless-steel shackle. The padlock body houses the combination locking mechanism. You can reset the Master Lock at any time for added protection.


Step 1

Open the lock using the current combination.

Video of the Day

Step 2

Insert the reset tool that came with the lock into the hole on the side of the lock. Turn reset tool in either direction 90 degrees. Leave the reset tool in the lock until you reset the combination.


Step 3

Turn the wheels to create a new combination. Remove the reset tool. Record the new combination, and store it somewhere safe in case you need to refer to it in the future.


If you lost the reset tool, you can purchase a replacement at a hardware store. The tool allows you to reset Master Lock's models 175, 176, 177 as well as model 178.


If you don't remember the new combination and you don't have it written down, you won't be able to open or reset the lock. You can store your new combination on Master Lock Vault, Master lock's free online database (see Resources section).

Video of the Day


references & resources

Report an Issue

screenshot of the current page

Screenshot loading...