The connection points between a toilet tank and bowl create an important seal, keeping water from leaking out of the unit as it passes from the tank to the bowl. If certain conditions are satisfied, it is possible to replace one of these items and continue to use the other.
When They Are Interchangeable
If the layout for the tank-to-bowl bolt holes and the spud gasket positioning match between the replacement tank or bowl and the old tank or bowl, the two parts will connect properly. When these holes line up, the bolts pass securely through the tank holes into the corresponding holes on top of the bowl. Also, the tank's spud gasket seats evenly into the bowl's water inlet hole, which is the large hole in the top rear of the bowl.
When They Are Not Interchangeable
You will likely not find a compatible tank or bowl if you have an older model toilet. With new developments and increasing array of toilet offerings, manufacturers discontinue models and replace past offerings with improved units. Also, some models use three tank-to-bolt holes, while others only use two. An arrangement like this will not fit together.
Why You Need To Swap Parts
On a two-piece toilet, irreparable damage may occur to the bowl, while the tank remains functional or vice versa. A crack in the toilet or bowl that springs a leak is an example of damage that necessitates a replacement. When this happens, seeking out a replacement for only the damaged part might save you the money and installation hassles of a full unit.
Obtaining a Replacement Part
Write down the manufacturer's name and the model number of the particular toilet part you wish to replace. Take this information to a home improvement, hardware store, or other outlet from which you plan to obtain a replacement. If the same toilet model is not available, ask a store representative to identify a tank or bowl from another model that will fit with yours. Look to salvage yards if you have an older model toilet. Also, visit the toilet manufacturer's website and order a matching part online, or locate a nearby dealer who offers the part.