Sunday, March 23, 2008

Replacing Your Moen 1200 Shower Cartridge


My house was built in the early 70s and finally my two showers gave out on me. First, it's just a gradual dripping, finally it grows to a stream.

Having done basic plumbing before (disposal, sinks, faucets, and toilets) I decided to give the showers a try.

Upon initial examination, it looked really straight forward. Pull out the old cartridge and put in a new one. Parts were readily available and tools looked easy enough.

After about 15 minutes, the obvious becomes clear. It's plumbing with caked on hard water minerals that have effectively welded it into place. Everything is seized up.

The instructions that come with the Moen replacement cartridge (and online) presume that you are working on stuff that is relatively new and nothing is seized up. They give you a cheap plastic tool that borders on a gag gift. You then realize why Moen sells a $40 tool, which again, that doesn't really work either. Ultimately you start having ideas of just cutting the whole unit out with a Sawzall and sweating in a new fixture all together.

Surfing the web for 5 or 10 minutes, you realize that you are not the first one this has happened to. The answer comes in the form of tap set and a bolt. Several websites make reference to this technique, but none really illustrate step by step. It's more or less a series of blog threads.

This article aims to illustrate the process showing the sequence of steps, things that go wrong, work arounds, exact tools, costs, and parts needed to fix your Moen cartridge replacement.

The extraction of a seized cartridge starts at step 11.


Simply put: You try and remove your cartridge, but it's seized up so much that bits and pieces break off trying to remove it.

Inherently in the design, you are putting 50 ft/lbs of pressure on a few millimeters of very soft and brittle brass. In the process of "turning" the cartridge, the "ears" snap off and all Moen provided tools become useless. The center stem and it's retaining ring pops out and the rest of the inner parts of the faucet come out leaving the outer casing of the cartridge stuck in the wall.

What you need is to get a lot more "surface area" so you can apply a lot more torque to the frozen cartridge. This comes in the form of screwing in a large bolt and using a half inch ratchet with an 18 inch bar on it. Stuff comes out pretty easy at this point.

Tools & Parts Used

Moen 1200 Replacement Cartridge

Long narrow flat head screw driver

Small circular wire brush

Plumber's putty

Plumber's grease

½" by 4 long hex bolt

Small pry bar

Vice grips

Needle nose pliers

½" tap & holder

Scrap piece of 2x4 (about 2 feet long)


¾" Socket for a half inch ratchet drive

½" ratchet drive with a long bar

Can of compressed air (optional)

Moen Replacement Cartridge

Estimated Time

About 1 hour depending on how seized up everything is.

Step by Step Solution

1. Turn off the water to your faucet if you can, else, turn off the water to your house. In my house, it's in the basement and looks like this:

Picture 1: Water Turn Off Valve In Basement

2. Start the disassembly of the unit. Pop off the cover with a thin flat head:

Picture 2: Cover Removal

3. Remove the handle:

Picture 3: Handle Removal

4. Remove the two screws holding the chrome Moen face plate (escutcheon) on:

Picture 4: Face Plate Screw Removal

5. Carefully use a flathead and remove the face plate. It will be "stuck" in place by hardened plumber's putty, so you will probably need to delicately pry all the way around it. Take care not to break the tile or dent the face plate.

Picture 5: Gently Pry Off Face Plate

6. Remove the chrome shield that goes around the faucet being careful not to bend or distort it:

Picture 6: Removal of Chrome Shield

7. Gently pull the retaining "U" clip up being careful not to bend it. This part is NOT provided with your replacement cartridge so you need to make sure it's not damaged during removal. There is a small hole in the top of it. You can use the edge of your flat head to pull up on it, and/or the needle nose pliers to pull it up. This is the clip that holds the cartridge in place and keeps is from rotating and coming out later on.

Picture 7: "U" Clip Removal

Note in the picture above, the U clip is partially raised above the stem. It's a bit hard to see but it's directly above the chrome stem in the center.

8. At this point, in a perfect world, your cartridge comes out with the cheap plastic tool provided with the replacement. The reality for most people is the plastic tool skips around and never gets a grip on the cartridge. This is illustrated on the Moen website ( as seen in step 4c.

9. If you can use the Moen extraction tool, great… the secret to this tool working properly is to line the tool up and TURN it as you gently try and extract the cartridge. Since I bought two replacement cartridges at my local Ace Hardware store, they loaned me their tool. Else, you can buy one for about $40 or so. The problem was the tool just snapped off the "ears" on my seized up cartridge and left me in a bind. Here's what the tool looks like and what happens when you can't get it to work right because everything is all seized up:

Picture 9: Moen Tool – Plastic

Picture 10: Moen Tool – Hardware Store

Picture 11: Moen Tool – In Use At Home

10. If you tried to use the tool, but only the center of the cartridge (stem) came out, then it looks like this:

Picture 13: Broken Cartridge Comes Out in Parts – Stem Only Separates from Cartridge, Retaining Ring Breaks Out, Ears Shear Off From Cartridge Caused By Tool Torque

In closely looking at this cartridge, I think the previous owner swapped it out some years ago with non-factory OEM equipment. It doesn't look like factory Moen. Notice the screen in the stem and the different markings and colors on it than a standard brass Moen.

What happened was the torque you put onto the tool grabbed a hold of the "ears" on the cartridge in the wall and the soft brass gave away and tore off as seen in the photo above. Notice in this picture, both ears have been torn off and it's flat on top of the cartridge. I also included the scrap of metal that broke off in the photo, too. This was one of the ears. Additionally, you see the retaining ring that once held the stem in place. That too tears out because of the pressure of pulling on the stem with the Moen factory tool.

11. Presuming that you are at this stage, neither of the Moen provided tools worked for you. At this point, you need to really get in there and apply some real torque to break the cartridge free. To do this:

A. Assemble together the ½ inch tap set:

Picture 14: Tap Set

Picture 15: ½" Tap Set Assembled

B. Put on your gloves at this point. The brass shavings that come out will stick in your fingers and hurt a lot if you don't.

C. Insert it into the tap into the hole where the parts from step 11 came out from:

Picture 16: Tap Set Inserted into Cartridge.

For purposes of clarity and illustration, this picture shows you a cartridge that is not in the wall. What you see is the tap looks like once inserted into the cartridge. Obviously at this point in the process, it's still in the wall.

D. Now, slowly press and turn the tap clock wise. For me, the tap just cut through the brass very smoothly. The whole operation took about 1 or 2 minutes. Cut about half an inch or so deep.

E. Now gently turn counter clock wise to remove the tap.

F. Next, take the 4 inch by ½ inch hex bolt and screw it into the hole you just tapped. Here is what it looks like:

Picture 17: Bolt Threaded into Cartridge

12. Follow the steps in this sequence before turning the bolt with any pressure.

A. Once the bolt is hand tight, I put my ¾" six point socket with the 18 inch ratchet. This gave me plenty of leverage to apply enough torque to break through even the hardest mineral build up.

B. Put a scrap piece of 2x4 above the faucet. Mine was about 2 feet long. This distributes the weight over the surface to keep the tile from breaking and provides a fulcrum to use for the crow bar.

C. Now put the crow bar behind the bolt head and in front of the socket. In effect, you have the crow bar positioned just like you would as if you were pulling a nail out.

D. I had my pal start turning the bolt clock wise with the ratchet pretty slowly as I was pushing into the crow bar.

E. At this point, the cartridge just starts to come out.

Picture 18: Extracting the Cartridge

F. Once the cartridge is exposed about an inch or so, then you can slap a pair of vice grips on it and pull the rest of it out by hand.

G. Here's what it looks like once you have pulled it out:

Picture 19: The Extracted Cartridge

13. Now that the original cartridge has been extracted, you need to clean up the hole. Use the small circular wire brush to gently clean off any hardened on minerals. Take care not to scratch or damage the pipe itself. If you have compressed air, blow out the hole of all the garbage that is lose (ex. Brass filings, mineral deposits, etc…). Or, you can turn the water on and just blow it out that way.

14. Take the replacement cartridge and put some plumber's grease around the outside.

15. Slide the cartridge into the hole.

16. Use the plastic tool to line up the cartridge so the "ears" are at the top and bottom. This is necessary so you can put the "U" clip back on. If the cartridge is not aligned, the clip will not go back in.

17. Put the "U" clip back in the slot on the top and gently push it in until it's flush on the shoulders leaving only the top part in the center sticking out.

At this point, most of the real work is done. It's just starting the re-assembly stage.

18. Chances are there's a lot of hardened old plumber's putty on the back of the large Moen chrome face plate. Break it off. It usually is pretty dried up and brittle.

19. Take a handful of new plumber's putty, roll it between your hands into a rope.

Picture 20: Making A Rope

20. Put this rope around the backside of the face plate.

Picture 21: Applying the Rope

21. Center the face plate up and press it onto your shower wall. Make sure to line up the screw holes at the bottom.

22. Slide the chrome cylinder part over the cartridge housing.

23. Put the two long screws into place, and turn them clock wise so they are holding the face plate onto the shower wall.

24. Line up the shower handle onto the stem of the cartridge. One side will be flat.

25. Now put the screw into the center of the handle and turn it clock wise until hand tight.

26. Pop the covering cap back onto the center of the handle.

27. Turn the water back on to the house.

28. Turn the shower back on and test to see if all is working well and no water leaking.

29. Clean up the job site. Brass filings will be in the shower stall and broken chunks of putty will be around. Put tools away.

30. Job is done.

Best Tips

Don't bother going with the Moen tools unless your stuff is relatively new. None of them seem to work. Go straight for the tap set and bolt.

Wear gloves. The brass filings hurt a lot when they get stuck in your hands.

Picture of Tools

Picture 25: All Tools & Supplies Not Pictured Earlier In Article

Cost of Tools & Parts

Moen 1200 Replacement Cartridge $39. 99 @ True Value

4" x 1/2" Hex Bolt $0.98 @ Home Depot

Tap & Die Set $44.94 @ Home Depot

1/2 Drive Six Point 3/4" Socket $2.99 @ Auto Value Parts Store

Online Resources

For other sites, Google on "Moen Cartridge Replacement" and many other threads come up.


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Saturday, March 22, 2008

Initial Posting: How To Fix Your Moen Cartridge

After spending a weekend of hammering on my Moen shower cartridge, I thought I would post my about my experiences on fixing it.

The following blog entry will detail the frustrations, tools, receipts, and solutions on how to replace the Moen cartridge in your bathtub.