Toilet Leaking Between Tank and Bowl and How to Fix It

After the installation and continued use of the toilet, it is bound to experience some problems. One of the most common problems reported involving toilets is a leak between the toilet’s tank and the bowl.

Constant Leaking

This goes on to show that the locknut may have come lose. It may also mean that the rubber washer found inside the tank has a excessive rubber or the porcelain surface on the inside of the tank is uneven or chipped leading to the leak. Below are the steps for fixing the leak in your WC toilet between the tank and the bowl.

Solution 1

With a pipe wrench, tighten the locknut with a ¼ turn, dry the area, and check if the leaking continues. Do not tighten any further if it has stopped. If the leak has reduced, keep tightening with a ¼ turn until the leaking stops. If there is no reduction in the leakage, disassemble the locknut joint and check for flashing (excessive rubber), improper fitting of the gasket, cracks in the flush valve threads and porcelain surface.

Solution 2

Check the rubber washer for excessive rubber or improper contact with the tank and flush valve. The porcelain tank may have chipped, or there is debris or dirt around the surface opening. Resolve the problem by cleaning out the bottom of the tank. In the case of a chipped porcelain surface, sand the area to remove the bumps. Replace the lock nut and if the leak persists, apply a silicone sealant on the underside of the flushing valve rubber washer to stop the leak.

Leaks After Flushing

For this type of leak, the problem is with the bowl to tank gasket. Ensure that the bowl and tank are touching the ridge. Tighten the wing nuts down until the bowl and tank touch. Remember to place the sponge rubber gasket before placing the tank in the bowl. Some toilet models do not have the ridge; instead, they have a rubber support to give the tank some stability.

You may require a smaller or larger gasket to seal the leak. Decide if the sponge gasket should be larger or smaller and purchase the one that will seal the leak. It is good to know who manufactured your toilet and it will be handy to call them if the leaking persists. A plumber’s putty will not seal the leak and so recommended is the use of a silicone sealant.

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