How to Replace Toilet Bolt Caps

Basic Replacement Caps

One of the most common types of replacement toilet bolt caps are those that consist of a plastic cap that snaps onto a base washer.

1. Remove Existing Nut

   To install this type of cap, you have to first remove the nuts and metal washers on the existing closet bolts using a wrench.

   If the nut and/or bolt are rusted in place, spray some penetrating oil on the assemblage, wait 15 to 20 minutes and try to remove it again.
   

2. Add Base Washer

   Slip on the new plastic base washer, then add the metal washer and nut over the plastic washer. Hand tighten, then use your wrench to snug up the connection a bit more. Don't overtighten.
   

3. Cut Bolt if Needed

   Sometimes—especially if the closet bolts weren't covered to begin with—they will be too long to accept the new caps. If so, you'll need to cut them down using a hacksaw or rotary tool. Use the cap as a guide and make the bolts as short as they need to be fit beneath it.
   

4. Install Cap

   To install the cap, simply fit it over the bolt and snap it onto the plastic base washer.
   

Threaded Caps

Threaded caps are an improvement over standard snap-on caps for a few reasons. First, you don't have to remove the nut and metal washer from the closet bolt. Instead, you just thread an adapter piece onto the bolt, and the cap snaps or threads onto the adapter. Second, some caps are tall enough so that you don't need to cut down the bolt. And third, the threaded caps stay in place much better than snap-on caps.

Threaded caps with adapters (such as those made by Danco and other manufacturers) are inexpensive and easy to install. Here are the basic installation steps, which may vary by brand.

1. Check Existing Bolts

   Make sure that the bolts coming through the base of the toilet are not too long. Many toilet bolts are quite long and normally are cut down when installing a toilet.

   If the bolts are too long to allow the toilet caps to sit flat on the toilet base, you will need to cut them with a mini hacksaw or a rotary tool with a metal-cutting disc. Try to cut as straight as possible so that the adapter for the new caps will thread onto the bolts easily. Hold the toilet caps next to the bolts to determine the correct bolt height, then cut the bolts short enough so the new caps will sit flush on the toilet base when they are threaded on all the way.

2. Install the Threaded Adapters Onto the Toilet Bolts

   A set of replacement toilet caps typically includes two different sets of threaded adapters: 1/4 inch and 5/16 inch. The 1/4-inch size is the more standard.

   Thread an adapter onto each toilet bolt with the notches of the adapter on the bottom. Make sure when starting to thread the adapter that it threads evenly and that it can easily turn a few times when tightening by hand.

3. Install Caps

   Thread the toilet caps onto the adapters, covering the bolts. Screw on the caps far enough so they sit flush against the base of the toilet.

   If you ever need to remove the toilet in the future, simply unscrew the cap and adapter to access the nuts.

   Tall Toilet Bolt Caps

   A relative newcomer to the toilet cap market is the extra-tall threaded cap, which is even simpler than threaded adapter-type caps but is just as secure. These caps thread directly onto the bolt with no need for an adapter. They're also tall enough that you don't have to cut down the bolt unless your bolts are uncommonly long. Tall toilet bolt caps come in 1/4-inch and 5/16-inch sizes.