Disposal sewer smell under sink

Here's some background for context: my kitchen sink has a disposal connected to a dishwasher and air gap. The handyman who installed the disposal forgot to punch out the drain plug and as a result when the dishwasher ran water would shoot out the air gap. I wasn't aware of the plug issue and proceeded to remove the entire disposal to investigate. Through research I discovered the plug and punched it out and then reinstalled the disposal the way it was installed before.

Now when I run the dishwasher it no longer shoots water out the air gap. However, sometimes bubbly smelly discolored water comes up a few inches in the disposal sink drain and a sewer smell comes from the air vent.

When the dishwasher is not in use the disposal sink drain smells fine, however underneath the sink has a strong sewer smell all the time.

I've tried to tighten everything as much as possible and I don't notice any water leaking, so I'm at a loss. Anybody know what might be happening?

Please see attached photos.

is your sink slow ?

frodo said:

is your sink slow ?

Click to expand...

is the sink draining slow ?

No, water from the faucet drains just fine.

JT1980 said:

No, water from the faucet drains just fine.

Click to expand...

disconnect the air gap fitting, take both hoses and connect them together.

then...using a wire. attach the hose to the sink clips



take the air gap fitting and saw off one of the pipes.
insert that pipe into both hoses. use as a coupling
you need something for the gear clamp to tighten down on, if not it would simply squish the hose

Thanks for the advice! Could it also be the dip in the black disposal inlet hose? That was the diagnosis from a thread I started here: http://www.doityourself.com/forum/t...posal-sewer-smell-under-sink.html#post2578098

By running the discharge line from the dishwasher to a high point, then dumping into the disposal as Frodo suggested will eliminate any dips and stinky water.

I'm in California so regs say I can't remove air gap. I have removed the disposal inlet tube and found a lot of standing stinky water. I shortened the tube to remove the dip. Hope it works! Again, appreciate all the help.

remove the air gap fitting and fill the hole with a soap dispenser, insta hot, or a cock hole cover

air gaps are ridiculous, not needed, ...........................................................i feel better now

I also live in California and don't know of anyone who retains the air gaps. That is valuable real estate at the back side of the sink. Soap dispenser, instant hot water, etc.