Partial clog after plumbing repair

Quick Answer:

If you hear gurgling and sinks drain slowly while testing a recent repair, first re-inspect the repair area, remove and clean the trap, and run water through a nearby cleanout to confirm flow past the repair. If that doesn’t clear it, snake from the repair toward the main to pull out dislodged debris. If you find leaks at the joint or the blockage persists, contact the repairer or a plumber for a camera inspection.

Why This Happens

Work on a pipe can dislodge small bits of solder, pipe sealant, drywall dust, or mineral scale. Those particles often collect in the trap or just downstream of a new joint and restrict flow without fully blocking the drain. Air moving through water traps can cause gurgling sounds when flow is reduced. Testing the repair by running water can reveal a partial clog that wasn’t obvious during the job.

Step-by-Step What to Do

1. Re-inspect the repair area

Look closely at the repaired joint and surrounding fittings. Make sure the trap and fittings are seated correctly and not rotated or misaligned.
Check for any visible drips or wetness at the connections. Small misalignments can leak slowly or trap debris.

2. Remove and clear the trap

Place a bucket under the trap, loosen the slip nuts, and remove the trap. Clear out any debris, construction dust, or sediment that built up during the repair.
Rinse the trap and the inside of the fittings before reassembling. A clean trap often restores normal flow immediately.

3. Open the nearest cleanout and test flow

Find and open the closest cleanout downstream of the repair (usually a capped fitting on the waste line).
Run water from the sink or another fixture into the line while watching the cleanout for steady flow. This tells you whether water is moving past the repair toward the main.

4. Snake from the repair toward the main

If the cleanout shows poor flow or you still have slow draining, insert a drain snake at the cleanout or the trap location and snake toward the main line. Work slowly to pull out dislodged debris rather than pushing it further down.
If the obstruction is close to the repair, start from the repair and snake outward toward the main so you clear material that may have been pushed during the repair.

5. Reassemble and retest

Reassemble the trap and fittings, hand-tightening slip nuts and ensuring everything is aligned. Run several gallons of water to confirm stable flow and listen for gurgling.
If flow improves, monitor the fixture for the next day to be sure the issue is resolved.

6. Call for camera diagnosis if needed

If you still have slow drains, or if you find a leak at the repaired joint, contact the person who did the repair or hire a plumber. A sewer camera inspection will show whether debris remains, a joint is failing, or there’s a deeper problem.

What Not to Do

Avoid assuming the repair was flawless and randomly re-tightening joints — that can break fittings or disturb seals.
Do not pour harsh chemical drain cleaners into or near the repair site; they can damage new seals, plastics, or metal fittings and create a safety hazard.
Call a pro if you find leaking at the repaired joint, persistent backups after reassembly, or if you can’t access the blockage safely.

When to Call a Professional

Call the repairer or a licensed plumber when you see any of the following:

Active leaking at the repaired joint that you can’t stop with a temporary catch bucket.
Repeated backups or slow drains after you’ve cleaned the trap and snaked the line.
Inability to access the blockage safely, or when you want a camera check to locate hidden debris or joint failures.

For related situations, see Partial clog after turning water back on and Partial clog after remodel.

Safety Notes

Wear gloves and eye protection when disassembling traps or using a snake.
Work slowly and catch wastewater in a bucket; dispose of contaminated water according to local rules.
Do not mix chemicals or use chemical drain cleaners near a fresh repair; they can damage fittings and create hazardous fumes.
If you smell sewer gas or suspect a major leak, vent the area and call a professional immediately.

Common Homeowner Questions

Why is the sink gurgling after the repair? Air moving through a partially clogged trap or line causes gurgling; clearing the trap or debris usually stops it.
Can I clear this with a plunger? A plunger may help for minor clogs, but remove the trap and check first to avoid pushing debris farther down.
How long should I wait before calling a plumber? If basic cleaning and snaking don’t restore normal flow within an hour or if you see leaks, call the repairer or a plumber for inspection.