What's actually causing this
Toilets run when water continuously trickles from the tank into the bowl. The two most common culprits are a worn-out flapper that doesn't seal properly, and a fill valve that's stuck open or set too high.
What you'll need
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Step-by-step fix
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1
Diagnose the problem
Lift the tank lid and add a few drops of food coloring. If color appears in the bowl within 10 minutes without flushing, the flapper is leaking.
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2
Turn off the water supply
Turn the shutoff valve behind the toilet clockwise. Flush once to empty the tank.
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3
Replace the flapper
Unhook the old flapper from the overflow tube pegs. Snap the new flapper in place and reconnect the chain — leave about half an inch of slack.
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4
Adjust the fill valve
If water is running over the overflow tube, the water level is too high. Adjust the float arm or float ball downward until the water sits 1 inch below the top of the overflow tube.
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5
Turn water back on and test
Slowly open the shutoff valve. Let the tank fill and listen for any continued running after the fill cycle completes.
In Los Angeles, tap water is hard (200–260 ppm). LA's water is moderately hard, sourced from multiple suppliers. Scale buildup is noticeable on showerheads and fixtures within 1–2 years. Water heater sediment accumulation is accelerated. Many households install water softeners or filters.
Plumbers in Los Angeles typically charge $120–180/hr. Most homeowners budget $800–2,500 for common repairs like fixture replacement, drain clearing, or valve repairs.
California requires state licensure (CSLB). Homeowners can perform some plumbing with a homeowner permit, but complex work needs a licensed contractor. LA Department of Building and Safety issues permits.
Post-WWII and 1970s-1980s construction commonly used polybutylene piping, which can fail and may be difficult to insure. Copper is standard in newer homes. Drought-conscious homeowners often retrofit to low-flow fixtures.
DIY in Los Angeles: California's licensing requirements are strict, but homeowner exemptions exist for simple plumbing and electrical. Most homeowners hire contractors for anything beyond basic repairs. Water efficiency retrofits are DIY-friendly.
- The tank or bowl has visible cracks.
- The toilet rocks or is loose at the base — this may indicate a wax ring failure.
- Water appears on the floor around the base after flushing.
Let Uncle AI diagnose it first.
Describe the problem. Uncle AI asks the right questions and tells you exactly what's broken — and whether you should fix it yourself or call someone in Los Angeles.
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