Jimmie's Guide to Rebuilding Toilets

Tired of erratic behavior from your toilet?

You have to hold the handle down because the "flapper" closes too quickly.

You have to jiggle the handle to get the flapper to close at all.

The toilet requires hearing protection when flushed, or sounds like a loud hissing water snake.

The toilet "ghost flushes" about every 2 or 3 hours.

You can of course call the plumber and spend about $200 - $300 to get if fixed, after a 2 or 4 week delay.
 OR: You can fix it yourself for about $40 - $50 bucks, AND clean the toilet and the area around it - the way you would want it to be cleaned. And maybe even paint the area behind the tank to match your wall color if you want to.
 How hard is it? It's probably a 4 to 5 on the D.I.Y. scale of 1 - 10. The newer plumbing parts all have simple connections, with rubberized washers that seal by hand-tightening in many cases. Other fasteners require only minor tightening with a wrench. Leaks are less common with these parts. Final adjustments are vastly simplified as well.
 So give it a try. The tips that I provide in this article should keep you out of trouble.

Do note that this article applies to "standard" toilets, with a separate tank and bowl, and standard flush and fill mechanisms.

Tools and Parts Needed


Fluidmaster #400ARHRK kit. This kit is recommended for the newer "low flow" toilets that use 1.6 gallons or less. There is also a #400AKR kit for older toilets, but the 400ARHKR kit also has a faster refill valve.
The "Fluidmaster" brand is quite popular for DIY plumbing projects. I have used their products for years and find them to be very reliable.
NOTE:This kit is for toilets with 2 inch flush valve opening - the most common one.

A braided connection line. Always replace this line when installing new toilet parts or new faucets. If the toilet has the original white plastic (unbraided) line (from when the house was built), this line is likely to be stiff and possibly prone to breaking.
Even if the existing line has been replaced in the past, they're only considered good for about 5 years.

Extra toilet tank-to-bowl bolt, washers, and nuts for toilets that have 3 bolts. The kit only comes with 2 sets of bolts. BUT see the Fluidmaster kit link right below. This link allows you to buy the Fluidmaster #400ARHRK kit along with their Kit #6102 (which has an extra set of the brass bolts and rubber washers) at the same time.

Not shown: For Gerber and Kohler toilets, it will be necessary to buy a special tank-to-bowl rubber gasket. That's the big red part shown at the bottom of the Fluidmaster kit. Gerber uses an extra thick gasket. Kohler uses a triangular gasket.

There are many types of braided lines!
 If your home is relatively new, you will likely need the top one shown here (also shown in the first picture). It is a "3/8 comp to toilet valve". The small metal nut connects to the water supply cutoff; the large plastic nut connects to the toilet. If a 5/8" wrench fits the small nut, it's likely a "3/8 comp" line.
 The other two lines in this picture have larger connecting nuts and are "1/2 flare to toilet valve" and "1/2 comp to toilet valve"
 Take a look (or even take a picture) of your existing supply line before going to the store. The lines come in various lengths. Usually 12 inch will reach.
 Need help trying to determine the correct braided line? It's likely in part due to the fact that plumbing parts have an extraordinarily sloppy nameing convention! I actually have a separate article which talks about this. It also has tips on selecting the right supply line. Just click the "Back" button above and select "Piping Terms Demystified".

parts parts

Ordering Information.

Here is some ordering information to help you get started. You can certainly get these parts at Home Depot, Lowes, Ace Hardware, and similar places as well, assuming of course that they have them in stock.

Here is the #400ARHRK toilet kit, combined with the #6102 kit, which has a couple of extra brass bolts and rubber washers. (It also has the big red rubber gasket, giving you a "spare".)

Here is a 12 inch braided line, "3/8 comp to toilet valve"

Here is a 20 inch braided line, "3/8 comp to toilet valve"

If you house is older than about 2000, your water supply valve may be bigger than "3/8 comp". So this is a "Universal" supply line, with adapters for 7/16 or 1/2 supply connectors.
 No need to guess which one you have.

kit 12 inch line 20 inch line Universal

 So here's the "preferred" tools:

A large wrench for tightening the big nut on the flush valve under the tank.

A measuring tape. This is to easily determine the various heights for the toilet parts.

A tubing cutter. This allows you to easily cut the flush valve pipe and leave a nice smooth edge.

"Open-end" wrenches are MUCH easier to use for disconnecting and reconnecting the braided line and for removing/tightening the tank nuts.
- 1/2 inch for the tank nuts
- 5/8 inch for the "3/8 comp" water supply line. 3/4 inch for the "1/2 flare" or "1/2 inch comp" line.

But these tools are adequate:

The large wrench

The measuring tape

A hacksaw for cutting the flush valve pipe.

An adjustable wrench.

tools tools

Extra stuff:
 A spray bottle of cleaner
 Some hand lotion. Why? Because the old rubber parts in the tank are deteriorated and extremely messy! The lotion helps you to more easily wash your hands when finished. Trust me on this!
 Paper towels (for the same reason)
 A large old towel to place under the tank while you are working on it.
 Some cutters (optional) for trimming the flush chain and possibly part of the flush handle
 A scraper (optional) for cleaning the old rubber deposits off the tank.
 (Not shown - for "covert" reasons): A shallow bake pan or similar shallow pan. In other words, you will have to sneak one out of the kitchen. It's not "potty water". It's "tank water".


Here's How to Do It

Here's a "Before" picture of a Crane toilet tank in need of an overhaul. Note the corrosion on the float arm.
 The assembly on the left is called the "Fill Valve". This is the old style valve - the same design that has been used since the 60s - and it uses a plastic or metal float to shut the water flow off.
 The item in the center is the "Flush Valve", whose red flapper is raised by a chain that attaches to the flush handle.

1 The first step is to shut off the water valve at the wall.
 But before shutting it off, wipe the shaft with a cloth dampened with a bit of the cleaning spray. Why? Because the shaft will be covered with dust. When the handle is turned, this shaft will slide past the shaft seal (often called "packing material"). We don't want the dust/grit to damage this seal.
 Also, before turning it off, make sure you know where the house main water shutoff valve is located! The reason is discussed next.

Before Clean

1a First of all, be careful in trying to turn it too tight! The shutoff valves with the nylon shaft can break! (Applies to both toilet shutoffs and water faucet shutoffs). This has happened twice to me, even in a relatively modern house - built in 2007. If this happens, you will have to turn off the main water supply. You aren't totally screwed if this happens. See steps 1c and 1d for a fix.
 So, the shutoff valve may continue to leak when you shut it off. And turning it too tight risks risks breakage. If it leaks too much, it will be necessary to shut off the main water supply. But also see steps 1c and 1d.

1b Here's another type of supply line. You will be doing a lot of good to replace this type of line with the newer braided lines. Note that this shutoff valve actually did what it was supposed to do: successfully shut off the water! (Yes. We live in an imperfect world. . .) You can ignore the next two sections.

Leaks white line

1c Do this sort of thing often? Maybe you may want to rebuild your neighbor's pots, or those of your parents or in-laws. If so, these items may be of interest.
 Does the water keep dripping, even though you have closed the water valve behind the toilet? The two parts on the left of this picture will enable you to fix the toilet without shutting off the main water supply. NOTE: This also applies to the valves that supply the kitchen or bathroom sinks, too.
 The upper left is a "3/8 comp cap". Remove the original water supply line and put the cap in its place. The black part on the lower left: You can make another type of "emergency cap" by cutting off the bottom of an old fill valve. I did this, and filled the internal cavity with glue and allowed it to harden. You would just leave the original supply line in place and just screw this "cap" into the white nut of the original supply line that you see in 1a and 1b above.
 Did your valve shaft break on you? The two pieces on the right are replacement shutoff valves. You can use the shaft/handle part to replace your broken shutoff valve without having to call a plumber to replace the entire valve.

1d This is one of the replacement parts shown on the right of the previous picture. Just loosen the nut that holds the shaft and handle in place. You don't need the remaining part on the left. This is the part that would have been connected to the water supply line. Thus you can buy any type of assembly, whose water supply line can be any diameter or connection method, as long as it has the shaft/handle part that matches yours.
 Then shut off the main water supply, and remove the nut on the original shutoff valve (which held the now broken shaft and handle.) Remove the broken part that's still inside - may have to use a needle nose pliers - or even a flat blade screwdriver. Then screw the replacement shaft/handle in the original shutoff valve. Now it's good as new (and you didn't have to call a plumber to go into the wall to replace the entire valve assembly).

Extra parts Replacement

2 Step 2 is to remove the toilet tank bolts. As I mentioned above, this is MUCH easier with a standard wrench (in this case a 1/2 inch) than trying to use pliers or an adjustable wrench.

2a Now you can lift the tank off and lay it on the old towel. This is a Mansfield tank, and it has 3 bolts.

tank bolts Crane tank

2b This is a Crane tank, and it has 2 bolts. Same for a Toto toilet.

3 Now remove the old rubber seal and remove the flush valve nut.

Mansfield tank flush valve nut

4 Clean the old tank. This one actually had rust from the original bolts. This is where a scraper will be handy. Some fine sandpaper also helps. The black stains from the deteriorated rubber washers actually wash off quite easily. Just about any countertop cleaner or even glass cleaners will work fine.

4a Here's the Crane tank all cleaned up. The stains around the bolt holes is OK, as long as the immediate area around the bolt holes is free of bumps.

dirty tank clean tank

4b And here's the Mansfield tank all cleaned up. It was much newer than the Crane tank. The white square shaft is part of the original flush handle assembly.

5 Here's your chance to clean the back side of the toilet bowl itself. Clean underneath as well.

clean tank clean bowl

6 Now we want to measure the height of the flush valve. The latest instructions that come with the Fluidmaster kits are MUCH clearer! No more "C/L", or "Critical Level" terminology! We simply want to make 3 simple measurements:

First measure the distance from the bottom of the square flush handle opening to the bottom of the tank. 10 inches in this case.

We want the top of the flush valve tube to be approximately 1 inch below this. (next section).

And we want to have the top of the fill valve to be approximately 3 inches from the top of the flush valve tube. (Sections 9 and 9a)

6a So measure from the bottom of the flush valve's black gasket. I have marked the cutoff point. 9 inches in this case.

measurement measurement

6c If you have the "preferred" tubing cutter, cut off the excess tubing. Just spin the cutter around the tube, while tightening the knob a little every few spins.

6d A hacksaw works fine, too. Just smooth off the cut with some sandpaper.

cutting cutting

7 Remove the large white nut from the flush valve, leaving the black rubber washer. Place the flush valve in the tank such that it does not cover any of the bolt holes. We want the tube to be toward the back, so that the flapper chain can easily reach the flush handle assembly.
 TIP: The chain hook that will connect to the flush handle assembly is secured, for shipping purposes. Unhook the chain at this point! It will be a lot easier than trying to do this when the tank is full of water!.

7a Here is a good orientation for tanks with two holes.

placement, 3 hole placement, 2 hole

7b Lay the tank on its back and attach the big white mounting nut. Hand tighten and then tighten only about 1/2 turn more with the big wrench. Because of the improvement in plumbing seals and gaskets, it is no longer necessary to "put the supertight" on plumbing parts.

7c Slide the big rubber tank-to-bowl gasket in place.

mounting nut gasket

8 Attach and tighten the tank bolts.

Place a black rubber washer on the bolt and slide the bolt through the tank from the inside.

On the bottom side, put a rubber washer followed by a metal washer, and then the nut.

Just loosely hand tighten first. Move the bolt from side to side and feel it contact the ceramic of the tank. Now try to move it to the center of the hole so that the bolt is not in contact with the ceramic. This will help reduce the chance of cracking the tank and will help isolate the tank acoustically from the bowl, for less water noise. Holding the bolt still, bring the nut up and hand tighten. Then use the wrench to tighten it snugly - but not so tight that the washer is significantly deformed on the inside of the tank.
This picture shows the three bolts and the tank-to-bowl gasket.

8a Here's the 2 bolt tank.
 NOTE: As you see in this picture, I did not put a rubber washer under the tank. I did this rebuild several years ago, and indeed the Fluidmaster instructions say to use just the metal washer under the tank. But I have had this method result in tank leaks in the past. Thus in my opinion it is better to have a rubber washer on both sides:
 You have two chances to stop leakage.
 You have an additional washer seal in case the inside of the tank happens to be rough around the bolt holes due perhaps to remaining material from the original bolds and washers.
 By using two washers and keeping the bolt away from the tank ceramic, you are keeping the tank isolated from the bowl and reducing water noise while the toilet refills. This is called "De-coupling" the tank.

gasket, 2 bolts gasket, 3 bolts

9 Carefully place the tank onto the bowl. Put a washer and a nut on each bolt and loosely tighten. If you have extra rubber washers, you can use them as well. In that case, put the rubber washers on first.
 Look at the tank from the front to see if it looks level. You can use a level on top, if you have one. Also make sure the tank isn't resting against the wall. There needs to be room for the tank lid edge to fit between the tank and the wall. (See "9a" on the right.) Rock the tank a bit while pulling or pushing on it when making adjustments (bolt nuts should be loose). Then hand tighten the nuts. For the three bolt tank, tighten the front two first.
 Now gently tighten the nuts with the wrench, until the tank is stable. Don't tighten very much. You will do the final tightening when the tank is full of water (when it's about 20 - 30 pounds heavier!)

9a This shows the tank being at least about 1/2 inch from the wall.

ttt ttt

10 Adjusting the fill valve length.
The fill valve is shipped at the lowest height. Lengthen it by grasping the grey shaft (move the float upward to expose more of the grey part). Grasping the black section, twist the black section to lengthen the fill valve.

10a Place the fill valve in the tank and measure. As noted above, you want the top of the fill valve to be approximately 3 inches above the top of the flush valve. The top of the flush valve was 9 inches from the bottom of the tank. So we add 3 inches for the top of the fill valve. That would be 12 inches, except that the top of the fill valve is almost even with the top of the tank. So it's11 1/2 inches in this case. Make sure the rubber washer is on the bottom of the fill valve!

Once the correct height is determined, you can secure the fill valve by attaching the locknut on the fill valve, under the tank. Hand tighten only. (Make sure the refill line nozzle near the top is sticking out to the right, toward the interior of the tank.)

fill valves measure 12 inch

11 Put a bit of WD-40 or light oil on the threads of the shutoff valve sticking out from the wall. This makes it much easier to tighten up the braided line nut without getting it too tight. Connect the braided line and tighten it until you feel the rubber seal beginning to compress. The newer seals do NOT need much tightening.

11a Now connect the large white nut of the braided line to the fill valve.
 Hand tighten this nut. It is helpful to use a dry rag to help you tighten the nut.
 Yes, it looks like a nut. NO!! You should not use a wrench to tighten it further. Hand tightening with a rag is plenty.

braided line connecting fill valve.

12 Before attaching the refill line, move the roller first. (The refill line directs some of the water down the flush valve tube to fill the toilet bowl itself.) If the line is not restricted, too much water will be wasted over-filling the toilet bowl. The blue assembly clamps the refill line. But you want to move the roller BEFORE attaching the refill line. Why? Beause it's hard to move the roller!

12a Before attaching the black clip to the refill line, hold the end of the refill line near the top of the flush valve refill tube. You want an arc, so that the top of the arc is a bit higher than the blue top of the fill valve, but not so much that the whole refill line is up against the tank lid. Doesn't matter if it touches the lid a bit. Cut off the excess; it's better to error in having the line too long - not too short!
Push the clip into the refill line and attach it to the flush valve tube. Yes, the clip is "Wierd"! Push it over the edge of the tube, with the metal part on the outside.

refill line refill line

13 You are ready to install the flush handle (or leave your old one if desired). If replacing, remove the existing handle. NOTE: For some reason, all flush handles have a reversed thread. You remove the existing nut by turning in the direction that would be used to tighten most fasteners. And you put on the new nut on "backwards", too.
 Remove the nut from the new handle and place it through the square hole. Note that you will attach the flush valve chain straight up from the red flapper. So, prior to installing, you could cut off some of the excess length (if any), to keep it from striking the tank lid when you flush.


14 Fill 'er up!

Turn on the water a bit. Water will slowly be going into the tank from the bottom of the fill valve. Use this time to check for leaks on the braided line. Gently tighten the small nut a bit more if necessary. Gently tighten the lwhite nut a bit more if necessary.
Note that you are actually more likely to have leaks if you got either of these nuts too tight (most of the time).

After the tank begins to fill, check the tank bolts for leaks. If you used a rubber washer on both sides of the tank bolt, you should be good.

No leaks? You can turn the water valve fully open now. These valves should always be left fully open - there is less chance of leakage around the shaft itself. The shaft is less likely to leak if you cleaned the shaft before turning off the water (#1 above).
After the tank has filled, retighten the 2 or 3 bottom nuts (underneath the toilet bowl). The tank is heavier now, so the nuts will likely be loose. Tighten gently. You don't want to crack the toilet bowl! Also make sure the tank is still at least 1/2 inch from the wall, if possible.

Tank water level:
Note that the water level in this picture is about 1/2 inch from the top of the flush valve tube. You adjust this level with the adjusting screw on the fill valve. It's a bit easier to use a phillips screwdriver.
Water level too low? Turn the screw clockwise. Water level too high? Turn the screw counterclockwise. (All of this is shown in Step 10, Step 11, and Step 12 in the Fluidmaster instructions.)

Bowl water level:
The red flapper has an adjustment. It's the large ring on the flapper. By default it is set to "maximum".
Did you have issues with the toilet stopping up prior to overhauling it? Then eat more fiber! In any case you can leave it at the maximum. This causes the red flapper to stay open longer. This will cause the toilet refill to take a bit longer.
But you can try turning the ring a bit (away from "maximum") for a shorter flush if desired.

Congratulations! No more holding the handle down, or jiggling the handle, or listening to random flushes. And, you have just saved a $200 - $300 plumber call-out.


Copyright © 2022 J.A.