DO-IT-YOURSELF : Toilet Tips Keep Problems From Overflowing

Before making any repairs, remove the tank lid and study how the various parts of a toilet tank work together. Most function the same way.

When you push down on the flush handle, the lift arm to which it is connected raises the tank ball or flapper valve at the bottom of the tank. The discharge pipe opens, and water flows from the tank into the bowl. When the tank is nearly empty, the tank ball or flapper valve falls back down, cutting off the flow.

The float, which looks like the pump of a large perfume atomizer, descends with the water level. It opens the valve at the top of the inlet pipe, called the ball-cock valve, just as the discharge pipe is closed. This allows water to enter through the thin tank filler tube. The float rises as the tank refills. When it reaches a preset level, the tank is filled, and the ball-cock valve shuts off the water prompted by the float and its arm.

When you need a replacement part, look for the manufacturer’s name and model number, which is often incised inside the lid of the tank. Buy a compatible part or bring the old one with you to a hardware store or plumbing shop and try to match it.

Here are points to check if a toilet fails to flush or doesn’t flush completely:

* After removing the tank lid, note how the flush handle and flush valve link. If the handle is loose, tighten it on its shaft and tighten the screw holding it to the lift arm with a wrench.

* You may need to reconnect or replace the chain or wire that connects the lift arm to the flapper valve or tank ball. Make sure the tank ball or flapper is securely screwed or hooked to the chain or wire.

* The water in the toilet tank should be about a half-inch lower than the top of the overflow tube. If it’s too low, raise the level by bending up the rod that connects the float to the ball-cock valve.

* If the water level is correct, check as you flush to see if the lift chain or wires pull the flapper or ball clear of the outlet valve seat. If not, reposition the wires or chain.

Here are some additional trouble-shooting tips:

* If the tank doesn’t fill and the water runs continuously, adjust the lift wire or chain so the tank ball or flapper drops straight into the valve seat. Gently scour the valve seat (the outlet to the bowl) with fine (No. 0) steel wool. Wash the tank ball or flapper.

* If you hear whistling, put new washers in the ball-cock valve plunger.

* Eliminate splashing sounds by repositioning the refill tube to eject water directly into the overflow tube. Or the ball-cock valve plunger may need new washers.

* If the tank sweats, insulate it by draining, cleaning and drying the inside. Then line it by cementing in sheets of polystyrene or foam rubber. You can get these in kit form. You can also have a plumber install a tempering valve that will warm the water in the tank.

* If the tank leaks, check the connections to the water supply line and tighten them if necessary. Also check and tighten the bolts holding the tank to the bowl. Over-tightening may crack the toilet tank.

* If the toilet leaks at the base, the bowl may be cracked. Or the wax ring sealing the bowl to the drain is worn and must be replaced.