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Install New Flush Valve and Gasket — Replace Gasket and Hardware

Beginner

Part of project

How to Fix a Leaking Toilet Tank-to-Bowl Gasket · Step 4 of 6

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In this video

With the tank removed, unscrew the large locknut holding the old flush valve and remove it. Install the new flush valve assembly, ensuring its gasket is seated inside the tank. Secure it by tightening the new locknut on the outside. Then, slide the new, thick tank-to-bowl gasket over the exterior locknut, pressing it firmly into place.

Goal: Install New Sealing Components

  • Make sure the flush valve is oriented correctly before tightening the locknut.

Used in this video

  • Channel-lock pliers (Tool Type: Pliers) · optionalTo help tighten or loosen the large flush valve locknut.
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FAQs

How long does replacing a toilet tank-to-bowl gasket typically take for a beginner, and what's the estimated cost?

For a beginner, this project generally takes 1 to 2 hours from start to finish, including draining and refilling the tank. The cost is primarily the price of a new tank-to-bowl gasket and bolt kit, such as the Fluidmaster Universal 2 in. Tank-to-Bowl Toilet Gasket System (2602G-008-T5), which is usually under $20. It's considered a beginner-level DIY plumbing repair.

Are all the listed tools absolutely necessary, or can I use substitutes for some?

An adjustable wrench and a 6-in-1 screwdriver are essential for disconnecting and tightening hardware. While a socket set, like the Husky 1/4 in. Drive Deep SAE Socket Set, can make removing tank bolts easier, an adjustable wrench can often suffice. A heavy-duty plastic bucket and plenty of absorbent towels (e.g., WYPALL L40 or HDX Select-A-Size Paper Towel Roll) are crucial for managing water and cleanup.

What safety precautions should I take, and what's the best way to prepare my bathroom before starting this project?

Always shut off the water supply to the toilet at the wall valve before starting and flush the toilet multiple times to drain the tank and bowl as much as possible. Place a heavy-duty bucket, like the Unger 6 Gal. Heavy-Duty Plastic Bucket, and plenty of absorbent rags or towels around the toilet to catch any residual water. Be careful when lifting the tank, as it can be heavy and awkward even when empty.

I replaced the gasket, but my toilet is still leaking. What could be the problem?

If your toilet still leaks after replacing the gasket, first check that the tank-to-bowl bolts are tightened securely, but do not overtighten, as this can crack the tank. Ensure the new gasket is properly seated and not pinched or off-center. Also, inspect the water supply line connection for leaks, and check the tank and bowl for any hairline cracks that may have gone unnoticed.

Install New Flush Valve and Gasket — How to Fix a Leaking Toilet Tank-to-Bowl Gasket (Step 4, Video 2) | Stesso