Plumbing kitchen sink strainer

The kitchen sink strainer basket provides a waterproof connection between the sink and drain pipe and also serves to trap food to prevent it from clogging the drain.
A leak under the kitchen sink could indicate that you need to replace the sink strainer. The first thing to do is to locate the source of the leaking water. If you find that it is coming from where the sink and drain come together, the kitchen sink strainer basket is the cause.
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Read on to find out more about how to remove and install a kitchen sink strainer.

About kitchen sink strainers:

Nothing is more annoying than a strainer basket that doesn’t remain open when you want it, which is most of the time, or one that doesn’t close easily to hold water in the sink.

Kitchen sink strainers are available in various styles and finishes including chrome, stainless steel, nickel, and bronze. They are available in price from under $10 to over $60 each. Be sure to buy a quality strainer that’s made from stainless steel or brass for your sink.

In fact you have to spend at least $50 to get a high-quality kitchen sink basket strainer assembly with a durable finish and a reliable stopper mechanism.

The spin-lock stopper doesn't have any parts that can wear, but screwing it in and out can be annoying.
The twist-and-drop style is much easier to use but requires occasional O-ring replacement.
The best kitchen sink strainer have either a spin-lock or a twist-and-drop style stopper.
Avoid push-in style strainer that have a non replaceable neoprene stopper or a plastic knob. The plastic parts break and can lose their sealing ability if exposed to boiling water.

Tools and Materials Needed to Install a kitchen Sink Strainer:

Depending on how your kitchen sink strainer attaches to the sink, the tools will include:

• kitchen Sink strainer
• Plumber’s putty
• Pipe wrench and/or strainer lock nut wrench
• Needle nose pliers or basket strainer wrench

Plumber’s putty is used to provide a waterproof seal between the sink and strainer.

Different sink strainers use different methods of attaching securely to the sink, and the tools needed may vary depending on the method used, but the types of kitchen sink strainer we will show you how to install  are a lock nut attachment sink strainer and a lock nut strainer with screw attachment.

1- Locknut Strainer with Screw Attachment:

Remove The Sink Strainer:

Start by removing the pipes that are connected to the old kitchen sink strainer.

Once the fittings are out of the way remove the old strainer nut with a large pair of pliers. This can be a little tricky sometimes. If you cannot get a good grip on it you may need to cut the nut out before you can remove the strainer. After the nut has been removed you can pull the old strainer out from the top of the sink.

Prepare Drain And Kitchen Sink Strainer:

Clean the area around the kitchen sink opening before installing the new strainer. There can be quite a bit of build up from the old strainer but it should clean up relatively quickly.

Separate the various parts of the basket strainer and spread them out within reach. Loosen the screws on the retainer.

Apply Plumber's Putty

Roll out a generous rope of plumber’s putty to a uniform width. Wrap it around the base of the kitchen sink strainer on the underside of the lip.

Set the strainer into the sink drain opening taking care to center it and align it as needed. Push it down slightly to allow the putty to adhere to the sink a little.

Install The New Kitchen Sink Strainer

From the underside of the sink place first the flexible washer then the metal washer into place over the body of the sink strainer. Hold them in place.

Thread the retainer on all the way before trying to tighten the screws. Next tighten the screws evenly and firmly with your hand. If you need to tighten a little more use a screw driver or pliers to finish tightening. Take care not to tighten so much that the rubber washer squeezes out of the strainer under the sink.
Note: If the washer squeezes out no matter what you try just remove the washer and use extra putty on the top.

Reinstall Drain pipes 

 Finally reinstall the pipes for the sink drain in opposite order of how they were removed. Turn the water on and check for leaks.
Note: to be certain that there are no leaks stop up the drain, fill the sink with water, and pull up the stopper. The extra pressure of the suddenly released water can make leaks more obvious.

2- Locknut Attachment Sink Strainer

Remove Drain Pipe Tailpiece

 Use a pipe wrench to loosen the slip nut that holds the drain tailpiece to the kitchen sink strainer by turning it counterclockwise. Once the nut is loose, unscrew it by hand, and remove the drain tailpiece pipe from the strainer.

Remove Sink Strainer Locknut

 Use either a special locknut wrench or a large pipe wrench to unscrew the old sink strainer (turn counterclockwise).

To keep the kitchen sink strainer from turning, insert either a special basket strainer wrench or needle nose pliers into the strainer opening.
Once the strainer locknut is loose, unscrew it by hand and remove the tailpiece and nylon washer.

Clean Kitchen Sink and Strainer

Use a putty knife or abrasive pad to remove any hardened plumber’s putty from around the strainer opening inside the sink. Follow this with a damp sponge and dishwashing liquid to remove any remaining putty reside or grime around the strainer opening in the sink.
If you’re reusing the existing strainer, clean the underside of it thoroughly as well. On new strainers, wipe off the underside of the strainer with a cloth or paper towel.

Apply Plumber’s Putty to Sink

After the kitchen sink and strainer are clean and dry, scoop out a golf ball sized glob of plumber’s putty, and knead it with your hands for several minutes to warm and soften it.
Once the putty is soft, use a back and forth motion with you hands to roll it into a rope of putty half an inch in diameter that’s long enough to go around the strainer opening in the sink.
Apply the putty around the sink opening, pressing it down in place. Insert the strainer in the sink opening, and press it firmly down so that putty oozes out all around it.

Attach Locknut to the Strainer

Remove any excess putty from the bottom of the sink opening and strainer, then slide the rubber washer onto the strainer from underneath the sink, followed by the friction washer.
Thread the locknut onto the strainer (turn clockwise), being careful not to cross the threads, and hand tighten the nut as much as possible against the friction washer and gasket.
Insert either a special basket strainer wrench or needle nose pliers into the bottom of the strainer opening to keep the strainer from turning, and use a locknut wrench or large pipe wrench to tighten the locknut up against the sink.
Snug the locknut up tight but don’t over tighten, which could break the locknut or strip the kitchen sink strainer threads.

Reattach Drain Pipe Tailpiece

Slide the nut on the tailpiece drain pipe, and screw it onto the bottom of the sink strainer with the nylon washer (flange facing toward the tailpiece) between the two.
Tighten the tailpiece nut up with a pipe wrench and don’t over tighten.
 
Then: you can Remove any excess putty from the inside of the kitchen sink around the strainer opening. Attach the tailpiece to the sink drain, and test it for leaks.