Leaking Moen Kitchen Faucet? Fast Fix With Free Parts

Moen is arguably the best manufacturer of faucets, be they kitchen or bathroom faucets. The faucets last for long, but you will need to replace the cartridges and O-rings after a few years, since they wear out and start to leak.

A leaking Moen kitchen faucet can be a common plumbing issue, but it’s important to identify the cause and implement the right solution to prevent water wastage and damage. Here’s a brief summary of common causes and solutions for a leaking Moen kitchen faucet:

Worn Out O-Ring or Cartridge:
- Cause: Over time, the O-ring or cartridge inside the faucet can deteriorate, causing leaks around the handle or base.
- Solution: Replace the damaged O-ring or cartridge with a compatible Moen replacement part. Be sure to turn off the water supply before disassembling the faucet.
Loose or Damaged Faucet Handle:
- Cause: Loose or damaged faucet handles can result in water seeping out from the handle area.
- Solution: Tighten the handle’s screw or replace the handle if it’s damaged. Check for wear and tear on the handle components.
Corroded Valve Seat or Valve Stem:
- Cause: Corrosion can affect the valve seat or valve stem, leading to leaks.
- Solution: Clean or replace the corroded parts, ensuring they are in good condition to prevent further leaks.
Worn Out Cartridge Seal:
- Cause: The seal within the cartridge can wear out, causing water to leak from the spout.
- Solution: Replace the cartridge, ensuring you choose the appropriate Moen replacement cartridge for your faucet model.
Improper Installation:
- Cause: If the faucet was not installed correctly, it may not create a proper seal, leading to leaks.
- Solution: Reinstall the faucet following Moen’s installation instructions, making sure all components are properly aligned and sealed.
High Water Pressure:
- Cause: Excessively high water pressure can cause faucets to leak or drip.
- Solution: Install a water pressure regulator to maintain safe water pressure levels throughout your plumbing system.

Single-Handle Moen Kitchen Faucet

This is the most common Moen kitchen faucet. It allows you to select the pressure as well as the temperature of the water using a single handle. If your single-handle Moen kitchen faucet is leaking, this is how to fix it:

Turn off water to the faucet. Look for 2 shut off valves (cold and hot water) under the kitchen sink. Shut them off by turning them clockwise. If you have push/pull valves, grab the handle and pull it out.
Turn on the faucet to drain out the water already in the hoses.
Remove the faucet handle. The faucet handle is usually attached to the cartridge using an Allen screw at the front of the faucet, which is covered using a tiny cap. Pry it off using a flathead screwdriver. With the cap out of the way, insert a 1/8 inch Allen wrench in the slot and loosen the screw. You do not need to remove it all the way out. Wiggle the handle a little and pull it out.
Remove the cartridge cover. This is the piece just below the handle that covers the cartridge. It is usually not threaded so you just need to pull it out.
Inspect the cartridge retaining nut. The cartridge is usually held in place using a plastic nut. If this nut is loose, the faucet will start to leak. Use an adjustable wrench to gently tighten the nut if it’s loose. Once that is done, turn on the water to the faucet and check if it is leaking around the cartridge. If there are no leaks then your problem is fixed.
Remove the cartridge retaining nut. If water is still leaking even after tightening the nut, shut off the water and loosen the nut and pull it out.
Replace the cartridge. Grab the cartridge stem with a pair of pliers and pull it out. If the cartridge has been in place for many years, it will not come out easily. Rock it about and then pull it out straight. Use a rag to clean the area where you just remove the old cartridge before pushing the new one in.
Push in the cartridge retaining nut and tighten it. Since this piece is made of plastic be very gentle as you tighten it not to strip the threads or even break it.
Slide in the cartridge cover and push it in all through.
Install the faucet handle and tighten the Allen screw.
Turn on the water to the faucet by turning the valves counterclockwise and in the case of push/pull valve pushing in. Check for leaks around the base of the faucet as well as from the spout.

Almost all of the time this repair is enough to fix a leaking single-handle Moen kitchen faucet.

Double-Handle Moen Kitchen Faucet.

With a 2-handle Moen kitchen faucet, the fix is rather complex as the leak could be coming from 3 different areas. These are the spout O-rings, hot water handle cartridge or the cold water cartridge.

To be sure which cartridge is leaking, turn off the cold water to the faucet and check if the leak has stopped. Now shut off the cold water and turn on the cold water and check the difference. Replace the leaking cartridge.

If you don’t want to fix the other cartridge in a few years’ time, you can as well replace both the cartridges as well as the spout O-rings. Here is how to do it.

1. How to Replace Moen Kitchen Faucet O-rings

If your double-handle Moen kitchen faucet is leaking from the spout (the bottom of the spout to be specific) then the O-rings are worn out and will need to be replaced. This is how to replace Moen kitchen faucet O-rings:

Turn off the cold and hot water to the faucet, but turn both the cold and water faucet handle on to drain out any water in the pipes. It is also a good test of whether the shut off valves are leaking.
Remove the cap. This cap is at the bottom of the spout, where it is connected to the sink. To avoid peeling off its finish, wrap duct tape, sand paper or a piece of cloth around it and grab it with a wrench. Turn it counterclockwise to loosen it. Please note that the design of these faucet differs slightly, but the process is the same.
Remove the top bearing washer. The spout is held in place by 2 washers, from the top and bottom. Simply lift off the top bearing washer and place it away.
Remove the spout. To remove the spout, wiggle it about and pull it out.
Pull out the bottom bearing washer.
Remove the O-rings. To remove the O-rings, you will either need to buy an O-ringer picker or improvise. Since you don’t intend to reuse the O-rings, pry them off with a small flathead screwdriver.
Clean the bottom of the spout. The bottom of the spout will most likely be covered by mineral deposits and other debris. Clean it with a soft rag or paper towel.
Grease the O-rings and bearing washers.
Slide in the bottom bearing washer.
Push down the O-rings, starting with the bottom one. To help the O-rings go down easily, I like to loop a thin thread through the O-ring. This helps to expand the O-ring and therefore move it down easily.
Slide in the spout followed by the top bearing washer.
Install the cap and tighten it gently.
Turn on the water and check if the leak has stopped

For spouts that are threaded directly to the faucet, the O-rings are usually on the spout itself. You just need to unscrew it at the bottom and replace the O-rings.

2. How to Replace a 2-Handle Moen Kitchen Faucet Cartridge

When you have determined which cartridge needs replacement, here is how to proceed:

Turn off water supply to the faucet and turn on the faucet handles to drain water from the pipe.
Remove the faucet handle. You will see a cap at the top of the faucet handle. Pry it off with a small flathead screwdriver to reveal a Philips screw that connects the handle to the cartridge. Remove the screw with a Philips screwdriver and lift off the handle
Remove the cartridge retaining nut by turning it counterclockwise with a wrench.
Remove the cartridge. Grab the stem of the cartridge with a pair of pliers and pull it out.
Clean the area. Once the cartridge is out, you will see mineral deposits or other debris in the area. Hold a cup or small bucket in an inverted position over it and turn on the water. The water will force the debris out. Have a towel to prevent water from spilling to the floor. Turn off the water when the area is clean. Wipe it dry with a paper towel.
Install the new cartridge. Align the tab on the cartridge with the slot on the faucet and pushed it down.
Put the cartridge nut back and tighten it.
Slide in the handle and secure it with the Philips screw.
Pop the cover back in.
Turn on the water to the faucet and check if the leak has stopped.

And basically that is how to fix a leaking Moen 2-handle kitchen faucet.

PRO TIP: If your kitchen faucet uses a gate valve shut off, you may notice it dripping after manipulating the valve. Tighten the packing nut by turning it ½ turn clockwise.

Moen Pullout Kitchen Faucet

The Moen pullout kitchen faucet is really well throughout. Its hose gives the faucet the flexibility that you need to perform various functions in the sink.

When the Moen pullout kitchen faucet is leaking, you will notice water dripping from the spout, the base of the faucet or under the sink. If the leak is from the handle, usually the nut connecting it to the head is loose and all you need is to tighten it.

On the other hand, if the leak is from the base of the faucet or under the kitchen sink, there is a hole on the faucet hose and you will need to replace it. Again, this part can be delivered to you for free by Moen if you contact them.

Whenever you have a leaking pullout faucet, my recommendation is to replace the hose. After all, you will get this part free of charge from Moen. Replacing it is also quite easy.

How to Replace a Moen Pullout Kitchen Faucet Hose

Turn off water to the faucet (hot and cold) and drain out the water already in the hose.
Remove the weight on the hose. Your hose has a weight on it under the kitchen sink which is the source of its tension. Release the weight by pulling the tab with your thumb.
Release the hose from the quick-connect. Press the button on the quick-connect to release the hose.
Pull out the old hose through the faucet spout.
Disconnect the faucet head from the old hose using a wrench.
Remove the wand screen from the old faucet head and replace it with the new one, not forgetting the O-ring
Connect the new hose to the faucet head and tighten it using a wrench.
Feed the new hose through the faucet spout.
Connect the hose to the quick-connect. As a confirmation, you will a click sound once the quick-connections are engaged.
Pull the hose down and add the weight on the marked section of the hose.
Turn on the water to the faucet and check for leaks.

This is the best way to fix a leaking pullout Moen kitchen faucet.