Water pools around the bottom of the spout, or runs down the outside of the faucet onto the sink deck, usually only while the faucet is on. This is not the cartridge. On a Moen it is one of three parts, depending on the faucet style.
Not sure this is your faucet? See how to identify your Moen cartridge without a model number, or how to find your brand and model.
Standard spout (no pullout hose)
The spout rides on two O-rings around the valve body. When they wear or dry out, water escapes under the spout. Fix: remove the handle and trim, lift the spout straight up off the body, pry off the old O-rings, clean the body, install new O-rings with Moen silicone grease, and press the spout back on. Use only silicone grease. Petroleum based plumber’s grease swells the rubber. The O-ring kit is model specific; for Chateau and Extensa spouts it is Moen 96778. Moen 96778 spout O-ring kit on Amazon
Pullout or pulldown spout
The usual culprit is the vacuum breaker inside the spout receptor, or the small screen washer where the hose meets the wand. Unscrew the wand from the hose, check the washer and its seat, and replace the washer if it is torn or flattened. If the leak persists, replace the vacuum breaker (part 101707 on many models).
Leak between the spout and the handle
If water comes out above the spout, near the handle, the cartridge O-rings are torn or the cartridge is not fully seated. Replace the cartridge. See the 1225 guide.
Leak under the sink after the faucet runs
Check the hose connections under the sink, especially where the pullout hose meets the supply block. Moen sells model specific hoses and will often send one under warranty. Call 1-800-BUY-MOEN with the model number.
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