Category Archives: Mechanical

Loosen Frozen Toilet Tank Bolts

So you have a leaking toilet and want to remove the tank from the bowl to fix it. However, the wing nuts on the tank bolts are so corroded, they’re stuck. Even a screwdriver in the slotted head of the bolt doesn’t provide enough leverage to break the weld between the bolt and its wing nut.

The tank has been removed for better visibility. In real life, the tank would still be attached to the bowl, of course. The wing nut has siezed up so hard, that any attempt to turn it ends up turning the entire bolt and nut assembly as a single unit, instead.

Two popular remedies are:

  1. Cut the bolt with a hacksaw blade (a bit of effort); or
  2. Grab the threaded part of the bolt below the wing nut with a vice grip (risk damaging the threads and making the nut even harder to remove).

I would like to suggest a third option below.

Presumably, you have already bought a set of new bolts to replace the corroded ones. Take two nuts and a washer out of the kit.
Thread one nut onto the bolt, leaving enough thread for the washer and another nut.
Put the washer and second nut on. It only needs to be finger-tight, as it will tighten as we go.
Use a wrench to turn the nut in the tightening direction, and use a pliers and turn the wing nut in the loosening direction. The wing nut should loosen, and can be removed. If you find that there is a second nut underneath the wing nut that is also frozen, repeat the same trick again.