Did you use plumber’s grease on all moving parts inside of this faucet when you installed the new cartridge?
They usually come with a real thin layer of grease on the cartridge.
Any time potable water can come in contact with such grease, it must be FDA approved grease that is safe for potable water situations.
This grease is usually called food grease and is clear and looks just like silicone that doesn’t smell or tighten up over time.
If water is surfacing at base of faucet, I am almost certain it is a small screw-in backflow assembly in back of faucet close to top. I just had one go bad on a customer’s faucet identical to what you describe and Moen will send it to you for free.
If you go to http://www.moen.com , you can see the spec sheet on what I am describing to you. Take housing off and turn water on, then off, numerous times and watch and see if it leaks from this small diaphragm.
» This message has been edited by DUNBAR on 24 August 2003