Toilet cistern repair - faults and their elimination. How to fix a leaking toilet The toilet is leaking

Any toilet leak always causes a lot of problems. It begins to spoil the mood, annoying the noise of continuously flowing water.

Large numbers appear on the water meter, and you have to pay several times more for water. The surface of the toilet begins to become covered with rust. Drops of condensate become noticeable on the pipes, which can cause corrosion and mold formation.

Tank leaks must be repaired immediately to avoid negative consequences.
Today, a leak in a toilet tank can be easily fixed without resorting to the services of specialists. But to do this, you need to understand the principle of operation of such a system and its components.

The tank can leak for various reasons. There is only one solution to fix it. Each tank design has its own characteristics. Therefore, the approach to solving such a problem will be individual. However, the most common is the “classical” design. Therefore, we will consider the problem of leakage, taking this design as a basis. We will give 7 solutions to the question of how to fix a leak in the toilet and why the toilet might leak?

First reason: Overflow

Perhaps the most popular and obvious reason was the banal overflow of the tank. When the toilet tank leaks water into the toilet. Excess water simply goes into the overflow hole. The main reasons for the appearance of such an overflow may be:

The rubber gasket has lost its elasticity. Long-term use of the tank led to loose shutoff of the water flow. The gasket began to deform and leak liquid;
The gasket does not press well and does not tightly close the outlet hole located near the drain valve, thereby creating a leak. This gasket has retained its elasticity and there are no signs of deformation. Water begins to flow due to poor pressure against the wall of the toilet;
The valve pin that holds the float may have worn out. This occurs during long-term use and the appearance of corrosion on the body of the stud;
A crack has formed in the valve body itself. Water begins to flow through it.

Note! When a brass valve is installed in the tank, there simply cannot be any cracks. They occur only on plastic products. Brass parts are highly reliable.

How to deal with such a leak

To quickly fix the problem when water leaks from the tank into the toilet, you need to find out the true cause of the tank leak. To do this you need to do a little testing.

Remove the toilet lid. Raise the float up with your hand. One centimeter is enough for the flow to stop. Consequently, the float arm is not bent quite correctly. It simply cannot shut off the water; it flows freely through the drain hole.

To correct and eliminate a leak, you need to slightly bend the lever so that it begins to shut off the water as soon as it reaches a certain edge.

If the leak does not stop after lifting the lever, you need to carefully inspect the valve. The special fixing pin must be in place. There should be no damage to it. It should stop the float lever while inside the valve. In addition, you need to check the condition of the hole in which the pin is located. It may have been deformed.

A stud that has become unusable can be replaced with copper wire of a large cross-section.

If the hole is deformed, a new valve must be installed.

It is possible that the leak appears due to the gasket. If, after pressing it against the valve, water stops flowing out of the drain hole, you need to adjust its pressure. If it cannot be adjusted, a new gasket must be installed.

We examined the main reasons and methods for solving the problem of tank leakage using the classical scheme. It has been used for over 40 years. However, every year new tank designs appear with a certain operating principle. Try to further study their design.

Reason two: Bolts

Quite often, leaking water is associated with the bolts that connect the tank and the toilet. Over the years, metal bolts become covered with rust, plastic bolts simply burst, which is why the toilet tank leaks.

How to solve this problem

First you need to thoroughly inspect all the fittings. Only one bolt may need to be replaced. However, in order to avoid additional runs to the store, it is better to immediately purchase a new set of spare parts for the toilet.

To accurately determine the cause of the leak, you will have to disassemble the tank. Sometimes it is simply not clear which part has failed and which requires immediate replacement.

How is the replacement performed?

To fix a toilet cistern leak you need to:

Before starting disassembly, you need to turn off the water supply;
Remove all water from the tank;
Unscrew the flexible line through which water is supplied;
Unscrew all bolts. If the body of the bolts is covered with a large layer of rust, they need to be cut off with a hacksaw. Buying new bolts is much cheaper than installing a new toilet. After all, the old one can be broken by unscrewing rusted bolts;
The toilet tank moves back;
The shelf lying on the cuff is removed;
The remaining water is drained;
All detected rust is removed.

For assembly, all steps are performed in reverse order. New bolts are installed, rubber gaskets are changed.

When tightening the bolts, the slightest distortion is not allowed. Tightening should be done with little effort. If you put too much pressure on the bolt, you can easily crush the earthenware.

Third reason: Pear

The rubber bulb has failed and the toilet constantly leaks after flushing. With prolonged use, rubber becomes inelastic. It becomes rough and cannot take the desired shape. As a result, water constantly flows in the toilet.

Solution

How to fix a leaking toilet? Repairing a pear that has lost its shape is practically useless. You can spend a lot of time, and the result will be zero. It is much easier to buy a new pear in the store.

When purchasing, you need to choose the softest one from several products. It can be used for a long period of time until it becomes hard.

The pear is fastened with a thread. To remove it, you need to turn the bulb clockwise. To install, the bulb is rotated in the opposite direction. While there is no new pear, you can use the weight hanging on the rod. He will put pressure on the bag and press it to the saddle. Any heavy nut can become such a load.

Fourth reason: Skew

A malfunction of the tank may be due to a skew or large displacement of the lever on which the float is held. There are many reasons for the formation of misalignment. For example, a hole through which water begins to enter the float. The lever may have moved slightly to the side due to prolonged use.
Another reason when the toilet tank is leaking can be low-quality plumbing parts purchased at the store.

How to solve this problem

If you purchased a bad float in a store, you need to change it to a more reliable and high-quality one. If a small hole forms in the float, it can be easily sealed with ordinary polyethylene. You can also use a lighter to heat a piece of plastic and close the hole.

But such repairs are considered temporary; the float will still need to be replaced.

Fifth reason: Depressurization

A leak appeared between the toilet and the cistern mount. Such a leak in the area of the connection between the tank and the toilet itself appears if the joint is depressurized. Usually the cause of this phenomenon is a large deformation of the rubber seal.

To eliminate the leak, a new gasket must be installed between the tank and the toilet.

This work is performed in the following order:

The water supply is turned off by closing the main water valve;
Remove all remaining water from the barrel by collecting it with a soft kitchen sponge;
Lightly unscrew the drain nut. It can be found directly under the drain valve hatch;
The screws that secure the tank to the toilet shelf are completely unscrewed. The tank is being dismantled;
The lock nut that holds the drain is unscrewed, after which it is removed from the tank;
A new gasket is installed. Each gasket is manufactured to specific sizes and shapes. Therefore, before buying a gasket, you must choose the exact size.
If the gasket is smaller or larger, the problem will remain unresolved;
The drain assembly is fixed with locknuts;
The tank is returned to the shelf and secured with bolts.

It must be said that a leak between the toilet and the cistern may be associated with other circumstances:

The bolt holding the tank container to the bowl is very rusty;
The insulation that seals the mounting hole for the bolt has become unusable.

Of course, you will have to install a new bolt and replace the seal. The work must be performed in the following sequence:

The water supply is cut off;
Drained;
All bolts are unscrewed and removed from the mounting holes;
Sealing washers are placed on the bolts;
The bolts are installed in place and tightened with nuts.

Your cash costs will be:

Gasket – 200 rubles;
A set of bolts – 50–300 rubles;
Master services – 1200–1400 rubles.

Sometimes no replacement is necessary. Simply tighten the loose bolts. To do this, hold the nut with a wrench and tighten the fasteners with an ordinary screwdriver.

Care must be taken when doing this type of work. Ceramic products are not very durable. Tighten the bolt too much and a crack may appear at the bottom of the barrel. To prevent this from happening, it will be much safer to simply install new gaskets.

Sixth reason: Shut-off valve

The shut-off valve has failed. This causes water to constantly flow from the tank into the toilet. You can, of course, try to disassemble the drain valve. Adjust the pressure of the hatch on the drain pipe by slightly sharpening its end. Such manipulations require a lot of labor, and the desired effect is not always achieved. This leads to a simple conclusion: there is no need to carry out repairs; it is better to completely replace the entire drain assembly, or the entire toilet cistern.

To do this, you must perform the following steps:

The toilet needs to have the water supply turned off. To do this, tighten the central water supply valve.
The remaining water is flushed down the toilet;
Open the lid and use a sponge to remove all remaining water;
Remove the fixing screws;
The tank is removed from the shelf;
The sealing gasket is removed;
The locknuts securing the drain assembly are unscrewed;
The old mechanism is removed;
A new system is being installed.

Before purchasing a drain unit, you should try to purchase a similar model that was previously in the tank. As a last resort, the same manufacturer. In other words, if the tank was manufactured by Cersanit, then the drain assembly should be of the same brand.

The new unit is secured with new locknuts, and a new gasket is installed.

We return the tank to the shelf, new bolts are inserted into the holes. We screw it to the toilet shelf.
All that remains is to connect the water and check the tightness of the new drain.

In principle, this work is not very difficult; it is enough to have a set of spanners and several adjustable ones.
Buying a new drain will cost 400–4000 rubles. It all depends on the type of mechanism. Elite systems are much more expensive.

If the work is performed by a professional craftsman, you will have to pay 1600-1800 rubles.

Seventh reason: Cracks

The toilet tank is leaking due to a crack in the bottom or sides. Such a serious problem can be dealt with without even replacing the entire toilet.

What should be done

The tank is detached from the toilet and dried well. Any cracks that appear must be sealed with a high-quality sealant. I must say that this method gives the greatest effect. Of course, the sealant is not designed for long-term use; you will still have to buy a new tank and toilet.

If the toilet cistern with the button starts to leak

First of all, determine what position the switch is in. If the return spring is weakened, the button may simply remain in the shaft. As a result, the drain hatch cover will always be in the “open” position.

To repair a toilet cistern with a button, you must follow a certain sequence:

The cover is being dismantled;
The falling switch is removed;
The spring is changed;
The seat is centered. It is located directly under the hole made in the lid.
Reassemble.

Preventative work

If you don't want your toilet to break down frequently, you need to constantly take certain preventive measures.

The toilet tank and bowl should be cleaned once every six months.

Constantly review the condition of fittings and related fittings.

Any toilet does not “like” mechanical damage; it does not tolerate temperature fluctuations.

Timely prevention will extend the service life of the entire system.

When a leak appears, the simplest breakdowns are corrected first and only then begin to solve more serious problems.

You can fix a cistern leak with your own hands. The design of the tank is so simple that it does not require any special tools. Having completed such repairs yourself, you will definitely get great pleasure.

Conclusion

We have given 7 of the most common solutions to why water flows in the toilet. In 95% of cases you have exactly the same problem. But if you've tried everything and nothing works, what should you do if water is still flowing in the toilet tank? It's better to call a plumber. He will fix the problem in less than an hour.

Plumbing fixtures wear out over time. Some parts require correction, others require replacement. Finding out about a breakdown is quite simple: the tank begins to leak, makes a lot of noise, and problems arise with flushing. But you can carry out repairs yourself, without special knowledge.

It is possible to carry out toilet repair work, because the design is quite simple. The toilet design includes a bowl and a tank. But most often breakdowns are observed in the tank.

The cistern operates on the principle of a water seal. Its system includes levers, a seal and a float. After draining, the water flows back into the container and at a certain point the shut-off valve is activated.

Signs of a problem with the tank:

Liquid constantly flows into the tank;
Water leaks from the cistern into the toilet;
To flush the house you need to press the flush button several times;
The flush lever doesn't work at all;
The toilet is leaking;
Lots of noise when draining.

The main thing is to correctly determine the cause of the breakdown, and repairs are not at all difficult. If there is a constant flow of liquid into the tank, the reason lies in the skew or displacement of the float. This breakdown can be fixed quite simply - you need to install the parts in the correct place.

The correct location of the float is determined 2.5 cm below the connection of the underwater pipe.

It is easy to turn off the water supply using a wrench. Inspecting the float often helps determine the cause of the leak. If the float is damaged, water flows into it and the element becomes heavier.

Repairing a float is quite simple. It is necessary to remove the element and pour out excess liquid from it. The chip should be repaired and reconnected to the system. But such repairs will only last for the first time; then you will need to completely replace the broken part. The resulting chips are repaired using heated polyethylene.

What to do if the toilet is leaking from below

If the tank is leaking from below, then the siphon membrane needs to be replaced. The same operation should be done if the water is not washed off for a long time. This process is quite simple to complete.

Membrane replacement sequence:

First, a crossbar is installed instead of the tank lid;
A float is connected to the crossbar;
All liquid should be drained from the tank;
The nut holding the pipe to the tank will need to be unscrewed;
The siphon nut is also loosened;
Then the siphon is removed;
After this, the membrane is removed and replaced;
Then all the removed parts are installed.

If the flush lever is not working, the rod is repaired. The broken part is removed and replaced with a new one. A homemade wire element is suitable for this. Over time, you can acquire new traction.

But most often the tank leaks water due to wear of the gasket between the toilet and the tank. There is a constant flow of water in the bowl, which is reminiscent of yellow spots. The worn element should be replaced with a new one. First, turn off the water and disconnect the flush tank from the toilet, then unfasten the drain. With this part they go to a plumbing store and buy a similar one.

In some cases, drain replacement is not required. Perhaps the problem is wear and distortion of the rings. They are either corrected or replaced.

When the tank is leaking, you need to check that the water level is correctly set. There is a special tube to drain excess liquid. It should be moved lower.

How to properly fix a leak between the tank and the toilet

If a leak appears between the tank and the toilet, then the reason is the depressurization of the device. Most likely, the problem is the deformation of the seal, a special rubber gasket. To fix the problem, you will need to replace the gasket.

Gasket replacement steps:

First, turn off the water supply;
The liquid from the tank will need to be drained, possible residues will also be removed;
There is a drain nut under the release hatch that should be loosened;
Then you should remove the tank by unscrewing the corresponding nuts at the fastening point;
You will also need to unscrew the drain;
Next you need to replace the gasket;
Then reinstall all parts back into place.

But the cause of the problem may also be an old rusty bolt that holds the container to the bowl. Next you will need to replace the damaged part. Also, first the water is shut off and the water is drained. The bolts will need to be removed and replaced with new ones. Sealing washers are required.

When purchasing gaskets, be sure to take into account their size, because the element is available in different forms. That is why you need to know exactly the dimensions of the part.

Sometimes you can only tighten loose bolts. To do this, just fix the element with a key and turn it with a screwdriver. But you need to be careful not to damage the ceramic bowl. That is why it is better to replace parts rather than constantly tighten them.

Securing the gasket between the cistern and the toilet

The gasket is one of the most popular fasteners. The advantages of such a part are obvious: small size and reliable fastening. But there is also a minus - a little pressure. To flush the drains, the tank needs quite a lot of water to operate.

Types of gaskets:

Shaped like a guitar;
Round;
Invoice.

The replacement takes place quite quickly. First, all communications are turned off. You will need to drain the water from the tank and disconnect it from the bowl. To do this, simply unscrew the bolts.

Older models have metal bolts and they will rust over time. Removing these elements using a key is not easy; you can damage the ceramics. It is best to treat the parts with a special liquid WD-40.

The rubber seal requires replacement. To increase sealing, use silicone sealant. You can apply a gasket or mount it in a special hole.

There may also be a gasket between the bowl and the toilet. It all depends on the chosen toilet model. This element acts as a shock absorber. This minimizes possible damage between porcelain and earthenware.

Modern toilets mostly come without gaskets. From the tank to the bowl there is a solid monolith. Using such a toilet is simple and convenient, but the cost of the device is quite high.

Proper functioning of the plumbing means a good mood and budget savings. However, it is not always possible to avoid water leaking in the toilet after flushing. Unnecessarily leaking water from the tank results in excessive water consumption. If water is constantly flowing in the toilet, what should you do? You can cope on your own without resorting to the help of specialists, but to do this you need to know the algorithm for identifying trouble, as well as ways to eliminate it. We will look at them in this article.

Why is the tank leaking?

Leaking water from the toilet tank means that the plumbing fixture is faulty. The following facts speak about this:

There is a constant noise of water entering the toilet bowl between flushes.

Cold water condensation collects on the pipes.

A rusty coating appears.

The numbers on the cold water meter are significantly higher than usual.

Initially, correct installation of plumbing equipment can help avoid such inconveniences.

Important! Breakdowns that occur in the future can be completely repaired on your own if you familiarize yourself with the possible causes and repair methods.

How the toilet works

Why does water run and how to quickly fix a broken toilet? Before determining the cause of the malfunction of the toilet barrel, it is worth remembering the principles of operation of the device:

Water enters the tank from the water pipe.

The reservoir fills, raising the float upward.

Having reached a certain volume, the liquid closes the drain valve and further filling with liquid stops.

By pressing the button when flushing (by pulling the chain or lever), the valve opens and water flows into the toilet bowl.

Then the filling process is repeated, however, if it breaks down, the toilet tank leaks, preventing the liquid from reaching the shut-off valve, or vice versa - it can overflow through the float.

Causes of failure

Before you begin to fix the breakdown and find out why water is constantly flowing, you need to understand its possible causes, and there may be several of them.

Incorrect installation

As a rule, new plumbing products that were installed incorrectly begin to leak within the first six months after installation.

You can find out why water is leaking and eliminate the cause of the problem by disassembling the device yourself and inspecting it for visible flaws and cracks. The operation of the shut-off valve should also be checked and corrected.

Malfunction of the drain device

After a long period of use, plumbing fittings wear out, causing breakdowns. Also, troubles may arise earlier if poor quality cistern fitting materials were used during the installation of plumbing.

To understand why water is constantly flowing in the toilet, what to do, you should close the water supply that is connected to the tank and observe the leak:

If water drains when the water supply is turned off, then the problem lies in the drain valve. This can be caused by salt build-up from water, blockages, or normal wear and tear. You can eliminate such a breakdown by cleaning the tank to remove any random debris or deposits.

If the water remains in the tank and does not flow into the bowl, then the reason lies in an incorrectly adjusted float or a clog in the automatic water system. In this case, you should try adjusting the water supply pressure.

We find and fix the breakdown

A drain leak can occur in different ways, so you must first determine exactly how the water flows:

Leaking through the overflow.

Leaks between bowl and tank.

The leak occurs before the overflow begins.

The water leaves through the overflow.

Along with the drain.

The toilet tank overflows and excess water overflows - this problem can arise for several reasons:

Mechanical damage to the valve body - such a breakdown can occur with a plastic fitting. Deformation or weak compression of the gasket.

Worn pin that holds the automatic drain lever.

Float lever displacement.

Important! Before you begin the repair, you need to prepare the following: wire cutters, gloves, pliers and new elements to replace the old ones. Also remember to turn off the water supply.

Lever offset

Lever misalignment is the most common cause of leakage. To fix the problem, it is enough to return the lever to its original position - strictly horizontal, below the pipe connection.

To eliminate other leaks through the overflow, proceed as follows:

Remove the reservoir cap.

Try adjusting the float by raising it a few millimeters.

If the leak stops, replace the float axis or straighten it (metal axis).

Important! Turn the float lever slightly to shut off the water earlier.

If the leak continues when you raise the float, pay attention to the valve. The pin in its composition may wear out, so it needs to be replaced with a new one or, as an alternative, copper wire should be used. In the place where the pin is attached, there must be a tight connection, as well as a complete absence of holes.

Important! If the leak continues with the valve gasket pressed tightly, the mechanism will have to be completely replaced.

Water flows away until it overflows (video)

If water constantly flows, either reaching or not reaching the overflow, then most likely the bolt that holds the shelf and toilet together is rusted or cracked.

It is worth once again making sure that water flows to the overflow level by performing a thorough inspection of the fittings, and if necessary, replacing several bolts or the entire set of fittings.

Important! It is advisable to give preference to brass fittings. Steel should be abandoned because it is less durable.

The solution involves disassembling the tank completely. So, proceed as follows:

Shut off the water supply.

Empty the cistern reservoir.

Shut off the water supply.

Unscrew the bolts that secure the toilet to the shelf.

Cut off rusty bolts.

Tilt the tank back, remove the shelf and place it on a flat surface.

Apart from the float and valve, disassemble all parts using wrenches and pliers.

During reassembly, replace all bolts with new ones.

Also replace or restore rubber gaskets using sealant.

Secure the tank with the shelf using plastic bolts. Roll the cuff towards the toilet and carefully place it on the shelf.

Important! If necessary, tighten the shelf with thick copper wire or a clamp, since it may also begin to leak over time, losing its elasticity.

The pear does not fit tightly

If the previous options are excluded, and the water still flows without reaching the overflow level, then it is worth considering another option. The rubber bulb acts as a membrane, opening and closing the water flow. But rubber products, when in constant contact with water, lose their elasticity over time and do not fit tightly, which is why water leaks.

To fix this problem, you need to replace the bulb. To do this, you need to unscrew it from the threaded rod counterclockwise. When buying a new pear, you should pay attention to a softer option, since such a product will last longer.

Important! The problem can be solved temporarily by using an additional weight, tying it to the lifting rod. Such a body kit will help to press the rubber bulb more tightly to the saddle, which will help eliminate leaks. Any heavy nut can be used as a weight.

Video material

To understand the issue, a toilet cistern with a button is leaking - what to do? , maybe not even a specialist. Initially, it is necessary to exclude all options for simple breakdowns, and only after this can you begin to disassemble the plumbing product to eliminate more complex problems.

Proper operation of plumbing means budget savings and a good mood. However, it is not always possible to avoid a toilet leaking after flushing. Unnecessarily leaking water from the tank causes excess water consumption. You can deal with the breakdown yourself, without resorting to the help of a plumber, if you know the algorithm for identifying the problem and how to fix it. The toilet is leaking, if you flush it, what should you do in this case?

Why does the toilet tank leak when I flush?

Why is water running in the toilet and how to fix and repair it? Leaking water from the toilet indicates that the plumbing fixture tank is faulty. The following facts speak about this:

There is a constant sound of water entering the toilet bowl between flushes.

A rusty coating appears.

Condensation collects on cold water pipes.

The numbers on the cold water meter exceed normal values.

Initially, correct installation of plumbing equipment will help to avoid such inconveniences.

Breakdowns that occur in the future can be easily corrected on your own by familiarizing yourself with the causes and methods of repair.

How does a toilet work?

Before determining the cause of the breakdown, why water is slowly dripping, you should remember the principles of operation of the toilet flush device.

How does a toilet work? Water flows from the water pipe into the flush tank. Recruitment in progress The reservoir fills, raising the float. Having reached a certain volume, the water closes the drain valve and further filling stops. When flushing, press the button (lever, pull the chain), the valve opens, water rushes into the toilet bowl. Next, the filling process should be repeated, however, the toilet tank leaks, preventing the water from reaching the shut-off valve or, conversely, overflows the float.

Causes of failure when the tank leaks water and leaks

Before you fix a problem, you should find out its possible causes. So, we can highlight the main ones.

Incorrect installation and can it be fixed?

Typically, new plumbing fixtures that are not installed to code will leak within the first 6 months of installation.

You can find out and eliminate the cause of the malfunction yourself by disassembling and inspecting the tank for visible cracks, defects and checking the shut-off valve.

Water flows after drawing and filling - a malfunction of the drainage device

After a long period of use, the fittings wear out, causing breakdowns. Also, problems may arise much earlier if low-quality materials for the tank fittings were used in the plumbing.

To identify the problem, you need to close the water supply connected to the tank and observe the leakage. If water leaks when the water supply is turned off, the drain valve is broken. This can be due to blockages, salt build-up from water, or normal wear and tear. You can get rid of damage by giving the tank a “general” cleaning to get rid of plaque and random debris.

If the water remains in the tank and does not flow into the bowl, then the cause is an incorrectly adjusted float, or a clog in the automatic water supply system. In this case, you should try to adjust the water supply pressure.

We identify and correct the breakdown that causes water to constantly flow from the toilet tank

Tank leak can happen in different ways, so you first need to decide how the water flows:

Leaking through the overflow.

The leak occurs before the overflow begins.

Leaks between bowl and tank.

Along with the drain.

The water leaves through the overflow.

The toilet tank overflows and excess water spills over the overflow. This problem occurs for several reasons.

Mechanical damage to the flush valve body (button), due to which water leaks

Breakage occurs only with plastic fittings. Deformation or weak, not tight seal of the gasket.

Worn pin holding the automatic drain lever. Float lever displacement.

Before starting repairs, prepare the necessary tools: gloves, wire cutters, pliers and new parts to replace the old ones. Don't forget to turn off the water supply.

Displacement of the lever after flushing the toilet - how to repair

The lever shifts when you flush– The most common cause of toilet leaks. To get rid of the problem, it is enough to return the lever to its original position: below the pipe connection, strictly horizontally.

To eliminate other leaks through the overflow:

Remove the reservoir cap.

Try adjusting the float by raising it a few millimeters.

If the leakage has stopped, then you need to replace the float axis, or bend it (metal axis).

Turn the float lever slightly to shut off the water earlier.

The leak continues when the float is raised - attention should be paid to the valve.

The pin in its composition may wear out, then it should be replaced with a new one or, as an alternative, use copper wire. In the place where the pin is attached there must be a tight connection and no holes.

The solution is to replace the mechanism. Constant leakage when the valve gasket is tightly pressed leads to the cost of a new device.

When the toilet starts leaking, there is no reason to feel joy: the noise causes irritation; the counter rolls up large numbers that will have to be paid; traces of rust appear on the toilet itself; Condensation appears on pipes and walls, which in the near future threatens to turn into corrosion, mold and rot. And in order to avoid negative consequences both for your nerves and home, and for your wallet, you should begin to solve the problem as quickly as possible. Fortunately, most cases where there is a leak from the cistern into the toilet are easily corrected, and you can deal with them on your own. You can see a simple solution to the problem of leakage from the tank into the toilet, cheap and cheerful in the video (in its own way it shows ingenuity in correcting problems):

Why does water flow from the tank into the toilet?
It cannot be said that there is only one reason for the leak and that this is the solution to the leak problem. The possible cause may be specific to each specific design. But nevertheless, the “classical” design has become widespread in our country, and consideration of leakage problems, as well as their elimination, will be considered on it. I also suggest watching an informational video that will allow you to understand the design feature of the functioning of the toilet cistern in order to better understand the nature of the leak:

Why does the tank leak #1?
The most popular reason is very obvious - the toilet tank simply overflows, and all excess water leaves through the overflow. And this reason has several reasons that lead to it:
Deformation of the rubber gasket during operation, when the rubber loses its elasticity and, due to loose shutoff, begins to let water through.
Insufficient pressure level of the gasket to the outlet of the drain valve. It was not deformed and did not lose its elasticity - the gasket is simply weakly pressed against the toilet part and because of this, water flows.
The pin holding the float in the valve body has become rusty or worn out during operation.
There is a crack in the body of the flush valve inside the toilet tank, through which there is a leak.

Attention! If a brass valve is used in the tank, then point No. 4 should not be taken into account, since cracks are the province of plastic parts, brass ones are too reliable.
Brass valves look like in the photo:
Why does the tank leak No. 2
If the tank does not overflow, but there is a leak, then what is the reason for the toilet tank leaking? The second popular cause of leakage is a problem with the bolt connecting the tank and the toilet itself. Steel bolts rust and leak, plastic bolts burst and water begins to leak.
Why does the tank leak No. 3
Another popular cause of leakage is a problem with a rubber bulb. The fact is that the pear, like any rubber part of the toilet bowl, loses its elasticity over time, becomes stiffer and no longer takes the required shape, as a result of which water begins to leak. You can recognize it by looking at this photo:
Why does the tank leak No. 4
It may also be that the drain tank is malfunctioning due to skew or displacement of the float lever. There are quite a few reasons for misalignment: there may be a hole in it, due to which water flows into the float, or it may simply have shifted during active use. Or the purchase of plumbing parts, the quality and service life of which, as well as the possibility of leakage from the tank, cannot be discussed.
Ways to eliminate a leak from a toilet tank
But if there are reasons why water flows from the tank into the toilet, then there must be ways to prevent this unpleasant and unprofitable action for the wallet. Now you can get acquainted with the best ways to overcome the problem when water flows from the tank into the toilet.
Solving the Problem Caused by Cause #1
You can solve the problem when water leaks quite easily, if you only know what the root cause is to blame for the flow of water from the tank into the toilet. You need to do a little experiment:
Remove the toilet lid;
Raise the float one centimeter. If the water stops flowing, the goal has been achieved. The problem is that the float arm is slightly bent and is now not shutting off the water and it continues to flow. To fix a leak, it is enough to bend it a little so that the lever shuts off the water more accurately when approaching the filling edge.
If the flow from the tank into the toilet has not stopped, then the valve itself should be inspected. Make sure that the retaining pin is in place, it is intact and, when used, secures the float lever exactly in the valve. You should also check the hole on which the pin is held: is everything normal and as it should be?
If the pin does break, it can be replaced with a piece of thick copper wire. If the hole for it is deformed, then you should go to the store for a new valve.
Are you reading this paragraph because others didn’t work? Okay, you need to press the gasket into the valve hole. If, when pressed, the water stops flowing, it means that the gasket is not being pressed well and needs to be adjusted. If your toilet continues to leak, you will need a new seal.

When examining the cause and ways to solve the problem, it was believed that the toilet cistern has a classic design that has been in use for 30-40 years. But given the continuous emergence of new designs of toilets and their cisterns, we can recommend familiarizing yourself with the principle of their functioning.
Eliminating cause No. 2
First, carefully inspect the fittings. Just a few bolts may need to be replaced. But just in case, it would be better to purchase a new toilet kit, since it is quite cheap. In any case, you should completely disassemble the toilet tank to understand why it is leaking and why it is leaking. So, if you discover problems that go unnoticed by the naked eye, you will be glad that you bought a full set of bolts. Replacement process:
Turn off the water supply to the toilet tank;
Empty the tank;
Disconnect the flexible line from the toilet tank;
Unscrew the bolts. If they are covered with rust, it is better to cut them down with a hacksaw. Purchasing bolts is always cheaper than purchasing a broken toilet due to the amount of effort involved;
After moving the toilet tank back, you must remove the shelf from the cuff that connects it to the toilet;
Drain the remaining water and remove rust from all places where you find it;
Repeat all the steps in reverse order, only with new bolts and it is advisable to replace them with new rubber gaskets, even if they are not yet deformed enough to allow water to pass through.

Warning ! When tightening the bolts, try to avoid even the slightest distortion, and also avoid applying significant force. It is very easy to crush the earthenware from which the toilet is made, or leave a crack in it.
Work and elimination cause No. 3
Since the pear has already lost its shape, repairing it does not make sense to eliminate the problem, from an economic point of view. The solution is to buy a new pear. In the store, you should ask for several pears at once, and choose the softest one, because over time they become harder and harder (you can see this from your own pear). The bulb is attached using a thread, and if you look at it from above, to unscrew it you need to turn it clockwise to remove it, and counterclockwise to screw in a new one. A temporary solution to the problem with the pear can be a weight suspended on the rod, which will press the pear to the saddle. The function of such a load can be performed by any weighty nut. I suggest looking at the photo where such a solution is played out.