Flush Toilet Mechanism FAQs

Q&A on How Flush Toilets Work, parts & features

The toilet flush valve lifting rod is stuck

Hi,

The lifting rod in my cistern has become stuck. There is a little bit of upward movement but if I try to push it down it remains rigid.

The rod is connected to the internal arm of the external handle via a double hook. Is there something obvious I am missing in trying to sort this out or do I need to replace any parts.

Any and all assistance gratefully accepted. Many thanks for your time. On 2018-11-02 by Phil Bell

by (mod) - Fix for stuck flush valve lift rod in a toilet

Phil

I suspect the problem is in the flush lever assembly. I've seen that happen when the flush lever rotates and gets jammed in the hole through which it protrudes into cistern (or flush tank on a toilet).

These parts are rather generic and inexpensive. I'd replace the whole assembly.

Unscrew the nut holding the flush lever on the inside of the cistern - it may rotate clockwise to unscrew - opposite of normal. Remove, replace.

When the toilet is flushed the bowl does not fill up with enough water

After a flush, the cistern fills up properly, but the bowl only fills up 1/3 to 1/2 of the normal water line.

When I turn off the water source and then turn it back on, the toilet operates as it should. What could be the problem? On 2017-02-20 by Frank

by (mod) -

First check the length of the pull chain that lifts the flapper valve that opens to flush the toilet. If the chain length is too long the valve doesn't pull up high enough and as a result it closes "early" in the flush cycle, thus not sending enough flush water volume into the toilet bowl.

Then Look for a clogged, loose, or disconnected tube that sends water into the bowl through the overflow tube while the cistern is filling.

When the toilet is flushed water splashes up from under the rim due to high pressure

When we flush the toilet, the water is entering the bowl so fast from the front holes under the rim, that the water is splashing up on the rim and seat. How do I fix this. On 2016-07-07 by Pete

by (mod) -

Unusual problem but not unique, Pete. It's possible that the main water passage into the bowl is partly obscured.

1. Check first that the toilet's main drain line is not partly blocked, causing the bowl to over-fill

2. Check that the tank fills just to the FILL LINE marked inside the tank cistern/reservoir.

3. With water into the toilet shut off, flush it and lift the flapper valve and look into the bowl passage for blockage

4. Try replacing the flapper valve and check that the pull chain is properly adjusted. There are some newer toilet flapper valves that include a dial that lets you adjust the flush strength and duration - I'd try one of those.

See more detailed fixes for a splashy toilet flush problem

at LOW WATER USAGE / POWER FLUSH TOILETS

Toilet tank doesn't fill after it's flushed

I just replaced a broken flusher valve for a brand new one of the same part number.

Now I have an intermittent problem: the tank doesn't fill after flushing. If I add some water to cover the valve it works fine. Testing several times passes.

When it doesn't work, I can't see any leaking from tank into bowl.

I also noticed, that if I watch the time I hold the lever down just enough to flash and don't keep it too long, the cycle works normally.

However, if over-holding the lever and the tank empties fully, I have a problem. Any adjustment recommendations? Thanks On 2016-05-23 by Igor

Igor, the flush valve is physically separate from the fill valve on most toilet designs;

Check first that the float assembly parts that move up and down in response to water level are moving freely. For example a bent flush lever arm that rubs against the side of the toilet cistern or against the overflow tube can cause the valve to fail to re-fill the tank with water.

Your fill valve itself may be sticking; if you can't free it by gently moving it up and down a few times it may be debris clogged and need replacement.

Check also to see if your fill valve is one of the new Fluidmaster models that includes a tank leak protection device; that will latch the float in the "up" position if the fill valve is not properly installed.

by Igor

Thanks for the answering. Fill valve doesn't stick. I checked on that. Float isn't in "up" position.

My theory now is that my new flush valve is a bit stiffer that the old, or, maybe a tolerance stack-up plays a role.

So, if all the water is let out of the tank, there is not enough pressure on the top of the valve to sufficiently hermetically close it. The water leaks down into the bowl and the tank does not fill.

I will try to play with water level adjustment. My bet is that nobody will try to let all the water out of the tank to fully empty it, if flashing will work more vigorously.
Regards
Igor

by (mod) -

Usually the toilet fill valve is operated mechanically by a falling float that slides on a vertical rod or by a horizontal float on an arm. Both of these floats mechanically open or close the fill valve in response to water level in the toilet tank or cistern; water supply pressure would not normally be the concern.

Look for a part that is mechanically binding.

How do I fix a leak at the toilet flush tank?

What should be done to water leakage from the flush tank in wc On 2016-03-27 0 by lakshmi

by (mod) -

Laksmi

We need to first find exactly what is leaking, then we know what to repair.

If the toilet is running - you will hear it, see condensation on the tank, or see water running into the bowl, that may require a simple adjustment or maybe replacement of the flapper valve

- search InspectApedia.com for TOILET RUNS CONTINUOUSLY

But toilets can also leak at the gaskets in the tank bottom, around the flush flapper valve (beneath it), or between the under-side of the toilet tank and the top of the toilet base or bowl, or at the bolts that mount the tank to the bowl.

If water is leaking onto the floor rather than into the bowl of the toilet, I suspect leaks are at the tank mounting bolts.

Sometimes gentle hand tightening of the bolts will stop such a leak. If not the toilet water supply is shut off, the tank is emptied, the old bolts are removed, and new bolts and gaskets installed.

Take care not to over-tighten the toilet tank mounting bolts or you can crack or break the tank - causing a worse flood and more costs than ever.