If a plunger and chemical treatments don’t work, it’s time to break out the plumber’s snake. The snake is a flexible metal coil that is fed through the pipes in order to reach the clog. Before making plumbing repairs, make sure the water supply at the faucet is turned off and drained.
The most practical way to snake out a clog is to disassemble the trap and snake directly through the drainpipe. If you would rather not remove the trap, you can attempt to snake through the sink drain. CAUTION: If a metal trap is thin or overly corroded, you might puncture the pipe.
To use the plumber’s snake, feed it down the drain, trap, or pipe until it stops. If the snake has a turn handle, position it about six inches above the opening and tighten the screw. Then rotate the handle to break up the clog. If there is no handle, move the cable by pushing and twisting at the same time, until it contacts the clog.
The first time the snake stops, it has most likely hit a turn in the pipes and not the clog. Maneuvering the snake past sharp turns takes patience and continued attempts. Continue pushing the snake forward and backward, while turning it. When the tip of the snake hooks the blockage, pull the snake back a short distance to free up some of the clog; then push the remainder on through.
If using the snake isn’t successful, the clog is most likely too deep in the pipes to reach it from the sink area, in which case you’re probably dealing with a main-drain clog. A main-drain clog will need to be addressed through the soil stack, the main cleanout, or the house trap.