Step 2. Remove the retaining
nut, if there is one, with channel-type pliers. A recessed nut with
notches can be removed with open needlenose pliers or a tool provided by
the faucet manufacturer. With other kinds, you’ll remove a sleeve and
three screws before extracting the cartridge.
Step 4. Purchase a
replacement cartridge. Apply heat-proof grease to the valve seat and
0-rings, then install the cartridge in the correct orientation and with
its tabs seated in the slotted body of the faucet.
Record the direction
the cartridge is facing by noting the orientation of some distinctive
part of the cartridge (some are cast with an orientation tab that
generally should point straight forward). Pull the cartridge straight up
and out with pliers. You may need to twist the cartridge back and forth
to break the seal.
Step 5. Reattach the handle,
remove the aerator, turn on the water, and test. If the faucet doesn’t
work, the cartridge may be facing the wrong direction. Remove it and
reinsert it facing the other way, still making sure the tabs fit into
the slots on the valve body.