I would like to readdress an old post regarding muratic acid (20% Hydrocloric Acid) to resolve rust build up in cast iron drains.
I would like any response based upon actual experience. The clog in question is in a cast iron tee which connects to the stack. This drain carries waste from bathroom sinks that are 8 feet way but have 14 feet of 2″ cast iron pipe before reaching the stack..
The rust buildup is approximately 12.5 feet from a cleanout located in the 2″ line at the point it connects to lead pipes that accend to the above bathrooms. This drain system has been troublesome for over 40 years and has had several treatments with liquid drano over the years. Presently the drain is mostly clogged. I can push the narrow end of a 3/8″ snake past the clog but the expanded end hangs up. NOTE: There is some sign of corrosion (not a leak) on the outside of the tee pipe.
The questions are…(1) Is muratic acid able to eat a way through the internal rust blockage before eating away the remaining pipe. (2) About how long should I let the solution stay at 20% before diluting with tap water. (3) Should I avoid putting the acid down the lead pipe sink drains. (4) Also has anyone notice the long term effect of using drano type products and can they accelerate the growth of rust in a cast iron drain system.
I realize the worse case is this may cause a leak of muratic acid that I will have to trap and contain. And that cutting the 2″ tee out and patching the drain system with a 2″ rubber tee is likely the inevitable course of action. I just wonder if anyone has had success using muratic acid to reduce or remove a rust blockage like this.
Thanks in advance for any comments based upon your personal experience.
Qis_Mo
Replies
No experience, but before I tried muratic acid I'd probably have a shot at using oxalic acid (a powder sometimes sold as "wood bleach"). It's generally a pretty good rust remover.
Removing clog due to rust buildup in 2" cast iron drain pipe
Thanks DanH
I am very interested in any approach to resolving this rust build up problem. I will certainly research "oxalic acid" and will look for a local source. Thanks again for responding with an idea not yet forwarded by other sources.
Qis_mo
If you can only get a 3/8"
If you can only get a 3/8" snake past the clog it sounds like the rust is all that's holding the pipe together. Have you had a pro come in with a big power snake and have a go at it? I think that would be my next move and if that didn't work I'd open the walls and remove as much of the old cast as I could get to.
On what do you base the assumption that the clog is caused by rust?
Rust that bad woukd be so severe that enough acid to clear it would eat the pipe thru, IMO.
U need a plumber, not a hazmat team
Pop used Grandma's house for 40 years as storage with the water disconnected , so the CI never sawrunning water, only what rainwater came down the vent stack.
When brother and I started fixing the place up, the bottom el at one stack and the trap under the basement floor were clogged with rust particles.
LONG hose on a big shop vac inserted thru the cleanouts pulled out all the rust and then it ran freely.
"This drain system has been
"This drain system has been troublesome for over 40 years "
This is the part that I don't get. Why not just fix it and be done with it. The only thing troublesome thing I am willing to put up with for 40 years is my wife.