Expert: no longer answering questions - 6/22/2009

Question
QUESTION: Where do I start in finding the solution to the following.  I have 2 bathrooms and whenever one toilet is flushed it causes the other stool to vent(bubble/glug glug.) My sinks all drain fine with nothing slow but,  when you first turn the water on in one sink you get a brief hint of the gas odor that the trap should stop. The septic system was recently emptied and checked all good.  Where do I start?

ANSWER: possible main drain stoppage or septic needs pumped out.

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QUESTION: The septic was just recently emptied and system checked good.  I think I've eliminated the main drain stoppage as I can open up the cleanout and it is clear to the septic.  Where do I start?  Possible vent issue??

Answer
Maybe a vent issue. If so diagnose whether it is needing to move air out or if it is sucking air into the system. If it's pushing out air, and the main drain is open then you need to run a vent from the noisy fixtures to the nearest large diameter drain line or any size vent line nearby. If it's sucking air into the system you need to install a studer vent under the closet sink to the group of fixtures that are making noise. This device allows the system to pull air in, but has a spring loaded flap that keeps it closed other times. If the system is pushing air then this will be a waste of time and money to install, you will need to run a vent to the existing system or outside on it's own. You may want to call a licensed plumber.