San Diego Plumbers › Plumbing Info › Plumbing Repairs › Clearing a Drain Line

Clear a Drain Line

A How to Guide on Clearing a Drain Line

If a sink is backed up but the clog isn't in the trap, it's probably further in the drain system – possibly in the drain lines inside your walls. To reach this kind of clog, you'll need a drain snake or auger. A tool designed just for this type of job. An inexpensive hand snake or auger comes with about 25 feet of flexible steel cable that threads easily into drain lines. The tip of the cable is designed to bore through clogs or grab onto obstructions so you can pull them out. With a little practice you'll be able to snake out a clogged drain in no time, easily.

Some clogs are a snap; others require a bit of patience. Plan an hour for this job. You are also going to need a few tools. Slip joint pliers, hand snake, and probably a bucket.

	Remove the trap and set it in a bucket. By hand, thread the end of the snake into the drain line opening until it meets some resistance. This usually means that the end of the snake has reached a bend in the drain pipe. To get past the bend, leave at least 6 inches of cable extending from the opening and tighten the cable lock. Crank the snake handle clockwise to move the end of the cable past the bend, pushing gently on the cable as you do.
	Release the lock and continue pushing the cable into the opening until you feel firm resistance. Set the snake lock and crank the handle clockwise. Solid resistance that prevents the cable from advancing indicates there's a clog. Some clogs, such as a sponge or an accumulation of hair, can be snagged and pulled out (step 4). If you can advance the cable slowly, you're probably boring through a soap clog (step 5).
	You can pull an obstruction out of the line by releasing the snake lock and cranking the handle clockwise to wind up the cable. If the cable releases suddenly, it may have lost its grip on the object and you'll have to try to snag it again.
	Bore through the soap clog by cranking the snake handle clockwise while applying steady pressure on the hand grip. Repeat the procedure several times, then retrieve the cable. Rinse the trap out in hot water (remember the drain line is disconnected!) Inspect the slip nut washer for wear and replace, if necessary. Reinstall the trap and tighten the slip nuts. Reconnect the trap and flush the system with hot water to remove debris.