Top Pick: The Korky 4010PK QuietFILL Complete Toilet Repair Kit ($30) includes everything to rebuild your toilet internals: fill valve, flapper, flush valve seal, and hardware. Quieter than Fluidmaster, easier to install, and fits most toilets. One purchase fixes 90% of toilet problems.
What’s in a Toilet Repair Kit?
- Fill valve — Controls water entering the tank. When it fails: running toilet, slow fill, or no fill.
- Flapper — Rubber seal at tank bottom. Worn flappers cause running toilets and phantom flushes.
- Flush valve seal — Gasket between tank and bowl. Leaks here drip onto the floor.
- Tank bolts & gaskets — Hold the tank to the bowl. Corroded bolts = leaks.
- Wax ring — Seals toilet to floor drain. Bad wax ring = sewer smell, water around base.
Our Top 5 Picks
Korky 4010PK QuietFILL Platinum $30
The Korky 4010PK is the gold standard for complete toilet rebuilds. Includes the QuietFILL fill valve (noticeably quieter than competitors), universal flapper, tank-to-bowl gasket, and mounting hardware. The fill valve has a simple twist-to-adjust height and works with most toilet brands. Easier install than Fluidmaster, and Korky’s customer service is excellent.
✓ Pros
- Quietest fill valve
- Universal fit
- Everything included
- Great instructions
✗ Cons
- Doesn’t include wax ring
Best for: Full toilet rebuild, running toilets, noisy toilets
Fluidmaster 400A $12
The Fluidmaster 400A is the best-selling fill valve in America for a reason—it’s reliable, adjustable, and fits virtually every toilet. If your toilet runs constantly, fills slowly, or won’t shut off, this is your fix. Installs in 10 minutes without tools. Not as quiet as Korky, but proven reliability.
✓ Pros
- Proven track record
- Extremely reliable
- Tool-free install
✗ Cons
- Noisier than Korky
Best for: Simple fill valve replacement, budget repairs
Korky 2021BP Universal Flapper $8
The Korky 2021BP is an adjustable universal flapper that fits 2-inch and 3-inch flush valves. The dial lets you fine-tune flush volume, and the rubber is chlorine-resistant (won’t degrade if you use tank tablets). If your toilet runs intermittently or you hear water trickling, this is usually the fix.
✓ Pros
- Chlorine-resistant
- Adjustable flush volume
- Fits 2” and 3” valves
✗ Cons
- Sizing tricky on some old toilets
Best for: Running toilets, weak flush adjustment
Fluidmaster 7530P8 Better Than Wax $8
Skip the mess. The Fluidmaster Better Than Wax is a rubber gasket that seals like wax but doesn’t squish, stick, or require perfect alignment. You can even reposition the toilet if needed—try that with wax. Works on any flange height and won’t fail like traditional wax rings.
✓ Pros
- No mess
- Reusable/Repositionable
- Stackable for low flanges
✗ Cons
- More expensive than basic wax
Best for: Anyone pulling a toilet, uneven floors
Fluidmaster 400CRP14 Fill Valve + Flapper $15
Can’t tell if it’s the fill valve or flapper? The Fluidmaster 400CRP14 combo replaces both for under $15. This covers 95% of running toilet issues in one purchase. Includes the 400A fill valve and a 2-inch flapper. Simple, effective, affordable.
✓ Pros
- Replaces both common failure points
- Excellent value
- Proven parts
✗ Cons
- No hardware or gaskets included
Best for: Running toilets when source is uncertain
When to Repair vs. Replace
Repair if:
- Toilet is under 15 years old
- Only 1-2 parts failing
- No cracks in porcelain
- Flushes effectively
Replace the whole toilet if:
- 3+ repairs in a year
- Cracks in tank or bowl
- Uses more than 1.6 GPF (pre-1994 toilet)
- Base wobbles even after tightening bolts
New toilets cost $100-300 and use far less water. Sometimes replacement beats endless repairs.
FAQ
Korky vs. Fluidmaster—which is better? Both work well. Korky is quieter and easier to install. Fluidmaster is cheaper and has a longer track record. You can’t go wrong with either brand.
How do I know which part is failing?
- Running + stops when you jiggle handle = flapper
- Running + never stops = fill valve
- Water on floor at base = wax ring
- Water between tank and bowl = tank bolts or gasket
How long do toilet parts last? Flappers: 3-5 years. Fill valves: 5-7 years. Wax rings: 20+ years unless toilet is moved. Tank bolts: 10+ years unless corroded.
Can I install these myself? Absolutely. Fill valves and flappers need no tools. Wax rings require removing the toilet (two bolts, 20 minutes). Most repairs take under 30 minutes.