Figure 7 shows a common type of flushing mechanism. Parts that usually
require repair are the flush valve, the intake (float) valve, and the
float ball.
In areas of corrosive water, the usual copper flushing mechanism may
deteriorate in a comparatively short time. In such cases, it may be
advisable to replace the corroded parts with plastic parts. You can
even buy plastic float balls.
_Flush Valve_
The rubber ball of the flush valve may get soft or out of shape and
fail to seat properly. This causes the valve to leak. Unscrew the ball
from the lift wire and install a new one.
The trip lever or lift wire may corrode and fail to work smoothly,
or the lift wire may bind in the guides. Disassemble and clean off
corrosion or replace parts as necessary.
Most plumbing codes require a cutoff valve in the supply line to the
flush tank, which makes it unnecessary to close down the whole system
(fig. 7). If this valve was not installed, you can stop the flow of
water by propping up the float with a piece of wood. Be careful not to
bend the float rod out of alignment.
_Intake (Float) Valve_
A worn plunger washer in the supply valve will cause the valve to leak.
To replace the washer--
Shut off the water and drain the tank.
Unscrew the two thumb-screws that hold the levers and push out the
levers.
Lift out the plunger, unscrew the cup on the bottom, and insert a new
washer. The washer is made of material such as rubber or leather.
Examine the washer seat. If nicked or rough, it may need refacing.
If the float-valve assembly is badly corroded, replace it.
[Illustration: _Figure 7._--Water closet (toilet) flush tank.]
_Float Ball_
The float ball may develop a leak and fail to rise to the proper
position. (Correct water level is about 1 inch below the top of the
overflow tube or enough to give a good flush.) If the ball fails to
rise, the intake valve will remain open and water will continue to
flow. Brass float balls can sometimes be drained and the leak soldered.
Other types must be replaced. When working on the float ball, be
careful to keep the rod aliened so that the ball will float freely and
close the valve properly.