What Happens When One of the Bolts From Your Toilet Comes Out?

If one of the toilet bolts comes out of its position, it will be one of the closet bolts that you find in the toilet base. The other bolts used in the toilet, which keep the tank secured to the bowl, might grow loose over time, but they won't come out. Repair the stray bolt before damage occurs.

How the Bolt Attaches

What you see of the closet bolt is the bottom end of it that sticks up through the toilet base. With the bolt installed upside down, the bolt head slides into a slot within the closet flange. The flange is the circular fitting that sits on top of the toilet's drain pipe, which you can see when the toilet is not in place. With the nut threaded onto the bolt from above, the bolt attaches the toilet securely to the flange, with a wax ring added to the union to keep out leaks.

How the Bolt Loosens

The bolt head is large enough to stay within the flange slot, when the bolt is installed correctly. If the bolt comes loose, it indicates that either it was not installed correctly, or the flange needs repair or replacement. One possibility might be that the flange is simply old and corroded. Another reason for the bolt to come out is when someone pushes on the toilet and moves it around on top of the flange, working the bolt out of the slot.

How to Spot It

Normally, the time you initially notice that a toilet bolt has come out is when you sit on the toilet and you feel it shift or move underneath you. The loose bolt allows the toilet base to move around. Or, you might notice water leaking out from underneath the toilet, sometimes accompanied by a sewer smell. This is because the loose bolt has allowed the toilet base to move and break the seal that the wax ring underneath creates.

How to Fix It

To repair the dislocated bolt, shut off the water to the toilet at the shut-off valve, which is the valve that the toilet's supply line coming from its tank connects to. Remove the bolt nuts and lift the toilet up from the floor. Examine the bolt and the condition of the flange underneath. Follow the directions of a toilet flange repair kit to repair the flange, and reinstall the bolt. The repair kit spans the break in a flange to give the bolt a sturdy slot to fit inside. If this kit does not repair the flange, remove the flange and replace it.