I have a toilet and wanted to change the caps that cover the toilet screw and nut that holds the bowl to the floor.

I tried to remove the screw to install the new caps that go under the washer and nut, and noticed that the nut is rusted and fused together with the screw and just turns all together and can't remove.

Toilet bowl screw and nut Toilet bowl screw and nut

How can I fix this?

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3 Answers 3


You probably should have just put the caps you had back on and backed slowly away...

Now you're going to have to destructively tear things apart until you can replace the rusted out parts. Might be able to use a nut breaker on the rusted nut to crack it off, otherwise probably going at it with a cutoff wheel and trying to not damage the toilet, dismount the toilet, hope the flange isn't rotted out so you can just replace the bolt, if the flange is rotted out you'll need to replace that...

When you buy new bolts, try to find brass or stainless steel ones. They will cost more. They will prevent this problem "next time."


Take the new cap, fill it with caulk and push it down over the rusty nut/bolt. When it dries it will hold on strong enough to stay in place until you can fix the problem correctly.

To do that, you'll need to cut the nuts/bolts off, pull the toilet, inspect/replace the flange, wax ring, etc.


That is nothing, just a foreplay of things to come.

the nut is rusted and fused together with the screw and just turns all together and can't remove. 

This is an indication that the mounting ring is also rusted.

Cut the screw off, and remove the toilet.

You might get some cosmetic scratches, those you can fix with porcelain patch.

Then be shocked how rusty the toilet mount ring is that you have to unscrew -replace.

But not before you might have to replace the rotten floor.

The seal around your toilet looks weak or non existent.

toilet seal

This gap should be filled with caulk.

There is also indication of mold.

Sopping list:

1- Wax ring (make sure you get the right hight)

2- Porcelain patch

3- Toilet mount ring with screws (S/S preferred)

4- Caulk -silicone

It should be against the law to sell iron screws in wet areas.

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