If you hear dripping water under the kitchen sink when it's full of dirty dishes and water, there's a good chance that there is a leak in the drain (or sometimes called the sink strainer). This strainer is a metal funnel that exerts pressure on the top and bottom of the sink. Over time, it will leak, crack, and change color and will need to be replaced. Luckily, with the right tools and a little bit of hard work, you can get rid of almost any rust on your sink – even replace it with a new one without the help of a plumber!
Step
Method 1 of 3: Removing the Drain Pipe
Step 1. Loosen the nut that connects the sink strainer to the drain pipe
These filters have always been made of metal, but most homes today use white paralon. You'll find some PVC nuts or metal nuts connecting the two components under the sink. Loosen this nut to separate it.
- You can loosen the PVC nut by turning it counterclockwise with your hand. Wrap the nut in a towel to make it easier to turn. Metal nuts may need to be opened with a pipe wrench or a large adjustable wrench.
- If you want, you can also remove the drain pipe in the trash can (the U-shaped part of the sink) to make it easier to work.
Step 2. Stabilize the rotating filter section to remove the hard nut
If the filter and nut to be loosened must be turned counterclockwise, hold the part from above. Insert small tweezers or a sink-only wrench into the drain to clamp the grate inside the filter (not the non-removable collection basket) to keep the entire filter from moving.
- You may be able to hold the tweezers in one hand and loosen the nut with the other, or ask someone else for help. This is a suitable task for teenagers or children.
- If you have trouble clamping with tweezers, insert the handle of the tweezers into the opening of the grate in the filter, then insert the screwdriver between the handles of the tweezers and hold it firmly to prevent the sink filter from moving.
Step 3. Decide what type of sink filter you have
The sink is equipped with a large lock nut that attaches to the thread on the outside of the filter. This system presses the washer and gasket to the bottom of the sink. Most modern sinks have a lock nut on the filter.
- There is also a filter lock nut equipped with a safety screw. There are usually 3 or 4 screws installed to secure the lock nut to the bottom of the sink.
- The bell-shaped sink filter has a bell-shaped outer “shell” that fits the size of the filter. This bell-shaped frame presses the bottom of the sink through the nut on the bottom of the filter (located just above the nut that connects the drain to the bottom).
Method 2 of 3: Loosen and Remove the Sink Filter
Step 1. Remove the screw on the locking part of the filter nut, if any
If you see a string around the wider part of the filter (when it's attached to the sink), you can remove it immediately. If there are 3 or 4 screws securing the lock nut, remove them before removing the lock nut and sink filter. Ordinary screwdriver (usually flower screwdriver), can be used for this purpose.
- After removing the screw, you should be able to loosen the lock nut by hand. Rotate the object counterclockwise until it releases from the latch and pulls out of the filter.
- If the entire filter rotates when you try to loosen the lock nut, use tweezers to clamp (or use a screwdriver held in place by the tweezers handle) the filter from the top. Use this method to remove the rotating sink strainer, whether or not using a lock nut.
- If the screw is difficult to turn, spray a little WD40 liquid and wait for 5 minutes. This is the reason you should loosen it up.
Step 2. Use a wide-mouthed wrench to loosen the filter lock nut
If the lock nut is not screwed in, you will need to use a wrench to remove the filter. Use a large wrench or – if you have one – a special wrench to open the filter lock nut that you can buy at a hardware store. Turn the nut counterclockwise with a wrench until it loosens, then turn it by hand until it comes loose and falls into the sink strainer.
If the lock nut is rusty and won't come off, you can use the cutting tool attached to the multipurpose tool to slice it, then (if necessary) use a chisel and hammer to split it. You can also ask a plumber for help to solve this problem
Step 3. Loosen and remove the nut on the bottom of the bell-shaped sink strainer
Take the wrench you used earlier to loosen the nut that connects the filter and drain pipe, then loosen the nut attached to the bell-shaped frame. Remove the nut, then pull the frame off the filter.
If the bell-shaped frame cannot be removed easily, insert a flat-head screwdriver (minus screwdriver) into the gasket gap between the frame and the bottom of the sink. Pry the frame, then remove it
Step 4. Shake the sink filter until it loosens, then push it up until it comes off
Shaking the object will separate the top of the filter and the top rim of the sink. After that, push up through the bottom of the filter with one hand and lift the filter out of the sink with the other.
- If the filter won't come off, tap it with a hammer from the bottom until it loosens. However, if you knock too hard, you could damage the sink. So, contact a plumber if necessary.
- Scrape off any dry putty or other debris that is on the rim of the sink (either on the top or bottom) before installing the new filter. Use a plastic putty knife to avoid scratching the stainless steel on the sink surface.
Method 3 of 3: Installing a New Sink Filter
Step 1. Make a ring of plumbing putty to place around the sink hole
Take some plumbing putty out of the package. Knead it for a few minutes to warm it up and make it more pliable. Once the texture is similar to a child's toy wax (like Play-Doh), roll it into a "snake" shape that's about the thickness of a pencil, then join the ends together to form a ring. Place this ring on the edge of the sink hole at the top and use your thumb to press it tightly.
- You can buy plumbing putty at any store that sells plumbing equipment.
- Make sure you've removed the old putty from the sink surface with a plastic knife.
Step 2. Press the new sink strainer into the putty ring
Regardless of whether you install the locking washer or bolt, the way to do it remains the same. Press the putty firmly so that it adheres tightly to the edges of the hole. You can use your fingers, a plastic knife, and a damp cloth to remove any remaining putty.
Step 3. Place the built-in washer and gasket between the bottom of the sink and the locking bolt or bell frame
The connection between the bottom of the sink and the locking bolts or bell frame which are both made of metal will not be really tight. New sink filters usually come with at least one rubber gasket and an additional gasket or ring made of rubber, cardboard (to protect the rubber), or other material. Install each item according to the instructions on the product packaging before tightening the locking bolts or bell frame.
If you want to replace the old filter, take the old gasket to a hardware store and purchase an identical (but new) replacement
Step 4. Tighten the sink filter from the bottom
To tighten the old lock nut, use a large wrench or a special filter wrench by turning it clockwise. Press the filter all the way down to the bottom of the sink, but don't screw it in so tightly that the two objects appear to come together.
- To tighten the screw-on filter lock nut, you only need to turn it by hand. This screw is the thing that tightens the lock nut and keeps it connected.
- For a bell-shaped filter ring, place the bell frame over the filter, then insert the built-in nut into the joint at the bottom of the filter. Use a wrench to tighten this section tightly (but remember not to screw it too tight).
Step 5. Connect the drain pipe to the sink filter
If this connection is made with a PVC nut, you only need to turn it by hand (clockwise). If the nut is metal, use a wrench to tighten it.
Step 6. Check for leaks
Install the sink, then fill it with water. Wait a moment, then rub a tissue around the joint between the bottom of the sink and the filter lock nut or bell frame (depending on the type of sink installed). If the tissue feels wet, the putty in it may not be tight enough so you'll need to reapply it.
