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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- Toilet flapper kit Shop →
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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 Portland, tap water is very soft (15–40 ppm). Portland has some of the softest water in the U.S., sourced from Mount Hood snowmelt. Mineral buildup is virtually non-existent. Soft water can cause corrosion in older copper systems. Many surrounding areas have well water.
Plumbers in Portland typically charge $115–180/hr. Most homeowners budget $800–2,500 for common repairs like fixture replacement, drain clearing, or valve repairs.
Oregon requires state licensing. Portland requires permits. Homeowner exemptions for owner-occupied single-family homes.
Mix of pre-1950s craftsman homes and post-1970s construction. Copper is standard in newer homes. Soft water means corrosion is less of a concern than hard-water metros. However, old copper may have pin-holing. Basement water intrusion common due to rainfall. Sump pumps frequent.
Freeze risk in Portland is minimal — hard freezes are rare. Pipe insulation is generally not a concern, though occasional cold snaps can surprise under-prepared homes.
DIY in Portland: Portland's moderate licensing and environmental focus support DIY repairs. Eco-conscious homeowners often handle water conservation and efficiency upgrades. Moisture management and mold prevention are common DIY focuses. Energy efficiency retrofits are popular.
- 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 Portland.
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