Reseal a leaking kitchen sink basket strainer

Dry everything and prove the first wet point

Water from an upper flange can run down and make a lower nut look guilty.

• • Dry the basket, tailpiece, and all nearby joints completely.
• • Run a small stream directly into the drain while watching the highest connection first.
• • Fill the sink shallowly and watch the basket flange/body to confirm leakage under standing water.
• • Mark the first wet point before disassembly.

Verify before moving on: The basket flange/body is confirmed as the leak source before it is removed.

Safety: If the sink, countertop, or drain assembly is cracked, badly corroded, unsupported, or cannot be safely held while loosening the basket, stop before applying more force.

Disconnect the drain below without twisting the plumbing

The basket must be free before its retaining hardware is removed.

• • Place a bucket below the assembly.
• • Disconnect only the tailpiece/slip-joint parts needed for access while supporting attached piping.
• • Hold the basket from above/below as required so torque does not distort the sink or attached drain.

Verify before moving on: Basket retaining hardware is accessible and downstream piping is supported.

Remove the basket and inspect every sealing surface

Basket condition: reusable and not corroded through. Reusing a cracked/corroded basket wastes the reseal effort.

• • Remove the retaining nut/ring and lift the basket without gouging the sink.
• • Clean old sealant and gasket residue from both mating surfaces with a non-damaging scraper.
• • Inspect threads, flange, rubber/friction washers, and sink opening for distortion or corrosion.
• • Confirm the selected sealing product matches the strainer instructions.

Verify before moving on: Mating surfaces are clean, undamaged, and compatible with the replacement/reseal materials.

Rebuild the basket seal in the correct layer order

The top flange seal and underside washers each have different jobs.

• • Apply only the sealant/putty type and amount specified for the selected basket and sink.
• • Seat the basket squarely from above.
• • Install underside gasket/friction washer/retaining hardware in the product's required order.
• • Tighten progressively while keeping the basket centered; stop before deforming a thin sink or squeezing out the entire seal.

Verify before moving on: Basket is centered, firmly seated, and retaining hardware is secure without sink distortion.

Reconnect and test standing water plus full flow

A basket seal should pass both static and high-flow tests.

• • Reconnect the tailpiece/slip joints with correct washer orientation.
• • Fill the sink and let water stand around the basket while inspecting below.
• • Release the full basin and watch every disturbed joint during high flow.
• • Dry and recheck after several minutes for a slow seep.

Verify before moving on: Basket flange and all disturbed drain joints remain completely dry.