A seasoned pro shows you how to remove a stuck cleanout plug to gain access to a stubborn clog in a drain line using pipe wrenches, heat and/or a hacksaw.
Snaking a clog in a drain line isn’t exactly neurosurgery. Just remove the cleanout plug and ram the snake down the line. But what if you can’t remove the plug?
“I see rusted-in cleanout plugs a lot in older homes with galvanized pipe,” says master plumber Les Zell. He recommends investing no more than 30 minutes trying to free one. After that, go to Plan B: Cut out a whole section of pipe and replace it with new plastic piping rather than beat yourself up and possibly break fittings.
“It’s much cheaper for my customers if I just hack out the old stuff rather than struggle with rusted connections for two hours,” Les says.
Les Zell has been a master plumber for 25 years and runs his own plumbing business. His passion is solar heating.
“My best advice for removing a stuck cleanout plug is to apply liberal amounts of rust penetrant to the stuck cleanout fitting at least one month before the line clogs up.”
Clean away any cobwebs, and shield surrounding wood with a metal baking pan. Grab a soldering torch and apply just enough heat to warm the cleanout plug and fitting. Don’t get it cherry red.
Soak the cleanout plug threads with rust penetrant. Then smack opposite sides of the tee or wye fitting at the same time using two hammers. Rotate the double blows around the entire fitting. Then try using a pipe wrench again.
Slip one pipe wrench onto the fitting and the second one on the cleanout plug. Then give it all you’ve got. If the plug breaks loose, you’re home free.
Start cleanout plug removal by applying gentle heat to the cleanout plug and fitting to soften the old pipe dope (Photo 1). If that doesn’t work, wait for the pipe to cool, apply rust penetrant, and then apply double hammer blows around the fitting (Photo 2). The vibrations from the shocks break up the corrosion and allow the rust penetrant to do its work. If the plug unscrews, go ahead and snake the line. But don’t reuse the metal plug. Buy a plastic plug and coat the threads with Teflon paste before installing. Then snug it up with a slip joint pliers (not the pipe wrench).
Use a reciprocating saw and a metal-cutting blade to cut out the fittings and the pipe leading to and from the cleanout wye or tee.
Slide the mission couplings onto the old pipe and slip in the new plastic fitting and repair couplings. Tighten the worm-drive clamps. Then wrap Teflon tape around the new plug and screw it into the adapter.
If the stuck cleanout plug won’t budge, saw off the old section (Photo 4) and replace it with new parts. Once it’s free, use the old fitting as a cutting guide to glue up a replacement wye, stub pipes and a new cleanout adapter (Photo 5). Don’t mess around with steel replacement parts. Go right to black ABS or white PVC plastic fittings and pipes and join them with rubber mission couplings. Slide both couplers onto the old pipe. Hold the new pipe in place and slide the vertical coupler into place and snug it up. Then connect the horizontal coupler. Tighten both to the proper torque.
Les’s Cutting Tip
Saw through the horizontal pipe, but leave about 1/4 in. of the pipe uncut. Then saw off the vertical pipe. The horizontal “tab” prevents the vertical pipe from wiggling while you saw. Then finish the cut on the horizontal pipe.
Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.
Keep a fire extinguisher handy.
Avoid last-minute shopping trips by having all your materials ready ahead of time. Here's a list.