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Mercer Toilet Repair Parts
by Toto

Toto Mercer Toilet

Replacement Parts for Toto Mercer Toilet
Two Piece Model MS756204SF
Tank #ST755S G-Max Flushing System 1.6 gpf

Parts diagram for Mercer toilets

Item # Part # Description Price & Quantity
1 TSU99A.X Fill Valve - Replaces TSU07A.5 & TSU08A.5 - (set height of TSU99A.X to notch 4 - refill ratio 5) $32.26 Enter a quantity and
528T "Will Fit" Replacement Fill Valve $25.72 Enter a quantity and
2 THU123 Fill Valve Diaphragm Cap - for original valve ONLY $7.76 Enter a quantity and
3 THU129ZE Flush Valve - includes flapper & nut - Replaced by THU129P-A Discontinued use THU441.10J-A
4 THU175S Flapper with Chain - Replaced by THU500S
Use arrow #7, chain length #13, and lever hole #1
$17.21 Enter a quantity and
2021 "Will Fit" Replacement Flapper $12.69 Enter a quantity and
5 THU441.10J-A Flush Drain - replaces flush valve THU129P-A $16.97 Enter a quantity and
6 THU440-A Flush Tower Assembly - (includes THU407 flush tower seal gasket) $11.80 Enter a quantity and
7 THU407 Flush Tower Seal Gasket $8.81 Enter a quantity and
8 9BU002E Drain Valve (flush valve) Gasket - fits THU129ZE, THU129P-A, and THU441.10J-A $4.57 Enter a quantity and
9 9BU024E 3" Tank to Bowl Gasket -
View Dimensions
$5.35 Enter a quantity and
10 TSU01D Tank to Bowl Mounting Kit $7.09 Enter a quantity and
11 THU163 Side Mount Trip Lever
(toilet color with chrome accents)
Select your color and
12 THU044S Bolt Cap Covers (1 pair) Select your color and
Not Shown Elongated Seat Toto® OEM Replacement Toilet Seat - Slow closing - view dimensions Select your color and
Not Shown Elongated Seat Premium Quality "Will-Fit" Replacement Toilet Seat by Bemis
- Slow closing with easy-clean & change hinge
Select your color and
Please note: The toilet seats featured here are the manufacturer's closest color match available & are non-returnable. View more Premium colored toilet seats.

Toto Mercer Toilet Parts Related Items

Frequently Asked Questions

Q. "How can I find the model number and color of my Toto toilet?"

A. Look inside your tank. Always exercise caution when removing the tank lid, as it is fragile and can be easily broken if stepped on or dropped. Inside your tank on the back wall of the tank or sometimes on the right hand wall (opposite the trip lever), you will see a model number stamped or engraved in the porcelain. Typically, for Toto toilets, you will see letters with a three-digit number. There may be more letters following, depending on additional features available on that model of the toilet. Elsewhere in your toilet tank, you will find a color code. Color codes start with a # followed by a two-digit number. The most common Toto colors are #01 - Cotton White, #03 - Bone, #04 - Gray, #11 - Colonial White, #12 - Sedona Beige, and #51 - Ebony.

How to find Toto toilet model number and color code

Q. "What's the difference between the original and 'Eco' versions of Toto toilets? Will the same parts work for both versions?"

A. "Eco" versions of Toto toilets have the same model number as the original version, but will have an "E" somewhere after the number. The only difference between the original and "Eco" versions is the amount of water they flush (1.6gpf vs 1.28gpf) - thus, they use a different flush valve and/or a different flapper that utilizes less water. The other internal components will typically be the same. Any internal differences will be noted on the product page.

Additionally, be aware that on occasion Toto has changed the NAME of certain lines, but the model number remains the same. For example, the Gwyneth one-piece is now the Ultramax II and the Gwyneth two-piece is now the Drake II. We have provided the most current names to better assist our customers, but please refer primarily to model NUMBER when selecting your toilet parts to ensure you're getting the right parts for your model.

Q. "How do the different Toto flushing systems work? Can I put parts from a different flushing system in my Toto toilet to change the gpf rate?"

A. Almost all of the Toto toilets (with the exception of a few older models that work like most other gravity-fed toilets), feature an extra wide 3" flush outlet and a larger trapway to deliver more water at a faster rate for a more powerful flush. We do NOT recommend attempting to put a different flushing system in your existing Toto toilet - toilets are designed holistically, meaning that the entire bowl, tank, internal parts, etc. are all designed to fit together in a very specific way. Even though some toilets might have similar parts and use similar technology, each toilet will perform differently based on additional factors like tank size, whether or not the porcelain has the Sanagloss finish, etc.

Learn more about the different flushing systems below:
  • Power Gravity: One of Toto's older flushing systems, this system was designed to provide maximum flush efficiency in low-profile toilets. Because of the smaller tank size, there is less water in the tank to "push" waste out of the toilet when flushing, but this is still one of the most powerful and efficient flushing systems for low-profile toilets.
  • G-Max & E-Max: As mentioned above, the big difference between the G-Max and E-Max flushing systems is the amount of water used per flush. As the industry moves toward all toilets being 1.28gpf, the E-Max is essentially a "retro-fit" of the G-Max design. Like most standard toilet bowls, the water rinses straight down when you flush - so you still get a powerful flush and rinse.
  • Cyclone: A Cyclone flushing system uses a single nozzle located at the tank end of the bowl just under the lip of the bowl which has no rim holes. When the toilet is flushed, water streams out of the nozzle towards the front of the bowl causing the water to swirl around the complete inside of the bowl. This Cyclone rinsing action not only completely cleans the bowl but effectively helps flush the bowl. The Cyclone efficiently out-performs other gravity flushing toilets.
  • Double Cyclone: The Double Cyclone is considered by many as the "best" Toto flushing system. It provides the same powerful flush as the Power Gravity, the G-Max/E-Max and the Cyclone systems, only better! Instead of one bowl entry nozzle the Double Cyclone has two opposite side rinse inlets flowing the same direction creating more swirling force than a single rinse inlet. Basically, the water quickly swirls around the bowl when you flush, causing a wash down effect that leaves the bowl cleaner - while still using only 1.28gpf.
  • Dual Max: This is Toto's first dual flush system - delivering only 0.9 gallons per half-flush and 1.6 gallons per full flush, without sacrificing the performance you expect from Toto toilets.
  • Tornado: The Tornado flush uses gravity and two powerful nozzles to create a centrifugal, cyclonic action reducing waste build-up. Water is forced to spin around the rim and bowl creating a more powerful flush. The two nozzles replace rim holes to maximize the bowl and rim cleaning action with less trapped dirt. This high efficiency dual nozzle water propulsion system is used for 1 gallon or 1.28 gallon per flush toilets. The Tornado flushing system is considered to be more effective in one flush than most toilets are with multiple flushes.

Q. "Toto uses many different letters before and after their numbers stamped on the inside back of the toilet tank. Are these letters just part of the number or do they have some significance?"

A. The letters shown with the part numbers are part of the Toto number and they are very significant. Each letter or combination of letters are different codes used by Toto to completely and accurately designate what the toilet or tank consisted of when it was sold. The letters MS listed before model numbers means the toilet includes a seat. The following is a list of letters Toto uses and what they mean: B=Bolt down tank lid; C=Cyclone or Tornado flush; CST=Gravity type toilet; CT=Bowl; D=Insulated tank; E=E-max 1.28 gpf; F=Universal bowl height 16.125"; G= Sanigloss or CeFiONtect (ceramic glaze); L=ADA height 16.5" high bowl; M=Dual-Max; R=Right hand tank lever; S=G-Max; ST=Tank; T=Drain valve tower type; U=Ultra low volume (1.0 gallon).

Example: CST604CUFG: CST=Gravity type toilet; 604=Ultramax II tank model number; C=Tornado flush; U=Ultra low volume (1.0 gallon); F=Universal height; G=CeFiONtect (ceramic glaze);

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Toilet Repair Information & FAQs

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