Moen Cartridge Replacement
I am also quite disappointed in Moen, at least their newer faucets.
Our old Moen single-handle lavatory faucets have been great -- never replaced a cartridge since they were installed, sometime between 1965 - 80 (before I bought the place). One has just developed a very slight drip from the faucet, but considering the horror stories I've heard about single-handle cartridges, I'm disinclined to fool with it until it gets worse. Even then, it might be easier to just replace the faucet instead (but not with Moen). Delta seems to be the choice.
I just replaced a Moen 1224 cartridge in my two-handle kitchen sink. We bought the thing at Lowe's (hardware chain), but I don't recall whether it was made in China or the U.S. -- didn't notice at the time, and didn't realize there are two "flavors" of Moen. We do have rather hard water from a 300-foot well, but I was surprised that the new Moen developed a serious leak (actually, failure to turn off completely) within 18 months. After spending much time on the Web , I tackled the replacement last night. The 1224 was stuck badly, and pliers on the plastic stem just slipped off again and again when I tried to pull the cartridge.
I read the hints about using vinegar or CLR to loosen the lime deposits, but I didn't see quite how the vinegar would reach past where the cartridge seemed to be "glued" -- so I made a "poultice" out of a paper towel. I soaked it in vinegar and then wrapped it around the cartridge, and kept it wet with vinegar for several hours, hoping something would soak in, somewhere, to help loosen it.
I then stuck the cross-style handle back on with the screw, to get some leverage. I first tried putting a rounded-jaw Vise-grip pliers around the stem, under the handle. The jaws didn't contact anything, just gave me something to tap against (upward) against the faucet handle & cartridge. After tapping upward on the Vise-grips (as close to the jaws & stem as possible) with a piece of pipe, it still wouldn't pop loose.
I finally decided that prying upward might work better, so I put a couple of small pieces of scrap wood next to the faucet stem, until they almost reached the underside of the Vise-grips, and then slowly pried upward in that gap (between the wood & the Vise-grips) with a small pry-bar. It took considerable force, but the cartridge & handle eventually popped straight upward.
Even though they don't make a "puller" for the 1224, if I were a plumber and did this very often, I'd make my own, based on the gear-puller principle. A piece of scrap metal with a hole in the middle, and a couple of bolts & nuts, would do this job quickly & safely.
This forum, and a couple of others, were of immense help in doing this job -- which is a lot scarier for an amateur than it should be. The Moen instructions on their website cheerfully tell you to just pull up with pliers ... well, it ain't all that simple, I can tell you.
I replaced the 1224 using a liberal amount of Danko waterproof silicone grease, to hopefully make this easier the next time.
In retrospect, I should probably have put a piece of rubber or something between the Vise-grips & the faucet handle, to keep from dinging the chrome on the underside of the handle. If I make a "puller" for the next replacement, I'll stick a piece of old inner tube where the plate contacts the handle.
Two odd points that I don't understand (and probably don't need to):
When I had the cartridge removed & was trying to rinse the vinegar out of the assembly, I happened to turn on the other faucet, which did not have its supply valve shut off. I was surprised to find that water poured upward from the hole where the cartridge had been, even though that supply (obviously) HAD been shut off. I tried it several times, quite mystified, but decided it did a good job of rinsing out the vinegar, at any rate. Not having a clue how the inside of a Moen faucet is designed, I don't understand how cold water gets moved over to the hot-water faucet. Might be simple for a plumber, but it's a mind-blower for an amateur!
Also, I examined the old 1224 cartridge and could see nothing really wrong, visually. Both O-rings seemed intact and still soft -- though they didn't sit as far off the cartridge as on the new cartridge. The symptom of this leak was a bit strange anyhow (to me): when I'd turn off the hot water faucet, it would feel like it had closed, but the water would still be running at considerable volume. Usually, when you'd open & close it a few times, it would eventually stop running, though often leaving a minor drip from the faucet, which might or might not stop in a few minutes. Not really having a clue how this thing works, I just assumed it was an O-ring problem, but apparently not.
Many thanks for your help here on the forum. It's a great resource, and I hope my experience may be helpful to someone else.