The faucet is leaking, we are repairing a single lever mixer

When water starts leaking from a kitchen or bath faucet, it's bad from any angle. It’s unpleasant to see a wet faucet, sink or sink every day and pay extra money for unused liters of water. But what is most dangerous is the risk of a possible flood due to a device that was not repaired in a timely manner.

Let's consider one of the most common plumbing products - a single-lever cartridge-type faucet with one control lever. If you notice that water is leaking between the body of this faucet and the adjustment knob, then the cartridge is probably not in order, which is either worn out and requires replacement, or is very dirty and needs deep cleaning.
To accurately determine the cause of a leaking faucet, it should be disassembled. This is not so easy to do, especially if the device has been in service for many years without disassembly, and the water is hard due to the content of impurities in the form of calcium and magnesium salts.
It should be noted that at first, the appearance of a leak can sometimes be stopped with the help of several turns of the handle in all directions.But then these manipulations do not give the desired result.
Do you really have to replace the entire faucet? But it is better to return to this costly option when other options have been exhausted. It’s worth trying to disassemble it and see what’s wrong. You may be able to cut costs by replacing only the worn part. Most often, this turns out to be the cartridge itself.

Replacing the old cartridge with a new one

For the job, we don’t need too many tools: a flat-blade screwdriver or a hexagon of a suitable size and an adjustable or gas wrench.
The first thing you need to do is remove the hot and cold water indicator plug on the front under the handle. Its second function is to close and protect the screw that secures the handle to the tap from moisture and dirt.

Sometimes you can remove it without difficulty, just pry it with the tip of a flat screwdriver on one side or the other, and then it leaves its place. In other cases, over many years of use, it becomes so clogged with dirt, grease and other debris that there is no way to move it without damaging it. But, what can you do, you have to do this too, otherwise you won’t be able to get to the latch that holds the handle on the tap.
The screw does not need to be completely unscrewed, the main thing is that it does not interfere with removing the handle. By the way, most often its dismantling does not go smoothly.

The problems are still the same: dirt, grease, hardness salts contained in the water, etc.
Between the handle and the faucet body there is a decorative cap, which also serves as a base, and the joystick seat moves along it when opening and closing the water and adjusting its temperature. It should also be unscrewed.If you use a tool, you need to be quite careful: the part is very delicate and can be easily damaged.


After removing the cap, we are exposed to a plastic cartridge secured in the mixer body with a nut. The most crucial moment of disassembly comes, but before that it is necessary to turn off the supply of hot and cold water.
We unscrew the nut using an adjustable or gas wrench, the jaws of which can move apart up to 32 mm. Then you need to lift the cartridge vertically up to pull its protrusions out of the holes in the mixer body.


Now you need to go to the store with the old cartridge to buy exactly the same one.

Without this, it is difficult to purchase a similar specimen, since they differ both in size and in the location and configuration of the holes.

We insert the new cartridge into the faucet body in such a position that it aligns with the holes in the faucet for hot and cold water, and the protrusions on the cartridge coincide with the holes in the mixer seat. The correct installation should also be confirmed by the angle of rotation of the handle (it should coincide with the range of movement on the old cartridge).


Next, tighten the nut that holds the cartridge. The degree of tightening should be optimal. If it is weak, the tap will continue to leak; if you overtighten, you can break the cartridge body. Also, over-tightening the nut will result in the need to apply great force to the handle and will cause unreasonably rapid wear of the cartridge.

Now you should put the handle in place, making sure that the locking screw does not interfere with this (its tip should not protrude into the gap of the seat square), and check the operation of the crane in various modes by changing the position of the joystick.

Then, having removed the handle, we install the decorative cap in place. We finally put the faucet control lever in place, tighten the fixing screw to the end and close it with a decorative protective plug, making sure that it is in the correct position, indicating which side is hot and which side is cold.

Cartridge repair

In some cases, a leak in the faucet can be fixed without replacing the cartridge. It is enough to remove the handle and decorative cap and tighten the clamping nut a little, but do not overdo it, otherwise the cartridge body may crack.
If tightening the nut does not help, then you can try to disassemble the cartridge, which consists of two halves, the upper of which is movable and the lower is stationary. Sometimes it is enough to wipe them with a cotton cloth, lubricate the surfaces with neutral oil and reassemble the device.
In other cases, grinding of the ceramic plates may be necessary. It is better to carry out the work on the surface of smooth glass. To do this, you will need fine sandpaper or sanding paste. Then the plates must be thoroughly washed and a thin layer of silicone grease applied to their surface.
If there is no desire to disassemble and repair the cartridge or it is non-separable, then the only option is replacement. For it to be successful, before installing a new cartridge, you should prepare a place for it by removing dirt and ceramic particles that have accumulated over the years of operation of the faucet, which can form when the plates rub against each other.

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