How to replace a faucet interior

Faucet tips How to replace a faucet internals
Replacing a faucet interior (cartridge) is a relatively simple job that you can do yourself. However, it is important to follow the right steps to avoid damaging the faucet.
What you need.

A new faucet interior
Water pump pliers/baco
Screwdriver
Towel
hammer
Rubber household gloves (for grip)

Roadmap

Close the main valve

The first step is to close the main valve. You do this to prevent water from flowing out of the pipes while you are working on the faucet.

Drain the pipes

Before you start dismantling the faucet, drain the pipes thoroughly. You do this by opening the faucets. If you are working on the downstairs, it is helpful to also turn on the faucets upstairs for a while to drain the entire piping system.

Disassemble the handle

The way to disassemble the faucet depends on the type of faucet. For a one lever faucet, you first remove the knob(s) from the faucet. You do this by usually prying off the cap on the back of the knob with a knife and then using an Allen (usually size 2.5 to loosen the Allen. Then pull the lever with a wiggling motion and the lever will come loose. Under the lever is often a convex ring, you can often loosen it by using a rubber glove to bake the ring (for grip) and then turn it.
If it is very tight, give a few taps on the ring so that it jerks and then turn the ring.

If you have a two-handle faucet, it may be that the levers/knobs are latched. You should then pull the knob with a bit of a wiggling motion and the knob will come off.

Remove the old interior

Once the faucet is disassembled, you can remove the old interior. You can do this by unscrewing the screws/nut or bolts that hold the interior. Or by unscrewing the interior with usually plug/ring wrench 17.

Install the new insert

Make sure that the washers from the old interior are not left in the faucet. Also check that the hole where the inner work sits is completely empty and clean. Insert the new inner work and make sure it is firmly in place. Make sure the rubbers on the inside are greased with faucet grease.

Assembling the faucet

Assemble the faucet parts in the reverse order of disassembly.

Open the main tap

Open the main valve and check that the faucet is working properly.
DIY tips

Make sure you buy the right inner workings. The insert should match the type of faucet .
Make sure the screws or bolts are tight, but not too tight (hand-tight).
Check that the washers from the old interior are not left in the faucet.
Run the faucet for a while to check for leaks.

Safety tips

Always wear gloves when working on pipes containing water.
Make sure the area is well lit.
Be careful when handling sharp objects.

Possible problems

If the faucet does not work properly, it may be that the interior is not installed properly. If so, check the installation again.
If the faucet handle turns the wrong way, you have ordered the wrong interior.
For faucets with levers, there is a Left and Right closing insert (see information).