Kitchen drain w/disposal rework

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by doc_u, Nov 2, 2008.

  1. doc_u

    doc_u New Member

    Messages:
    11
    Location:
    SF California
    Have a poor situation with the existing setup in our new (to us) house. When the disposal, (which is currently installed on the left (larger) bowl of the double-bowl sink) is turned on when the sink has water in it, debris and water shoot out of the right hand sink, unless the drain plug basket is in place.

    When the disposal/bowl is not full of water, normal operation is seen, and no water or debris enters the second bowl.

    The rough-in is at 12.5" on center and the disposal outlet arm is at 13.5" under this current setup.

    However, apparently due to the rough-in being at the FAR right side of the sink cabinet, there appears to be some extra length and bends in the trap, which I suspect may be causing this issue.

    [Pics attached]

    What I would like to do is move the disposal to the smaller bowl, and rework the plumbing so that it will work properly.

    However, due to the love affair with ABS and glue that was used here, I'm not sure how to actually remove this in a way to enable a proper reconnection.

    Should I cut the ABS off at the wall, and glue in a threaded fitting so that I can attach whatever to it?

    Thanks,
    - Doc

    Attached Files:

  2. Basement_Lurker

    Basement_Lurker One who lurks

    Messages:
    668
    Location:
    Victoria, BC
    Unfortunately the installation you have there is quite a mess! Changing around the fittings aren't going to solve the major problem of your wall stub-out being way too high; it's that 90 fitting that's causing most of your problems and unless you can lower the drain sub-out, there really isn't much that you can do about your sink drain backing up (a backwater valve is a possibility, but nothing I would bother thinking about first).

    Did you try cleaning out the p-trap?
  3. doc_u

    doc_u New Member

    Messages:
    11
    Location:
    SF California
    Moving the disposal to the right bowl would raise the outlet from the disposal approx 1.25", so the new height will be at 14.75" vs the 12.5" of the current rough-in.

    Is this enough to make a positive change? I'd really like to try to fix this without ripping open the wall, if at all possible.

    Yes, all pipes that I can remove have been cleaned. That elbow-to-elbow and glue monstrosity cannot be removed except with a hacksaw. This may be next weekend's projects.

    Thanks for the reply.

    -Doc
  4. Terry

    Terry Administrator Staff Member

    Messages:
    15,294
    Location:
    Bothell, Washington
    [​IMG]
    If the proper fittings were used under then sink it would be better.
    Most people use a slip joint baffle tee to connect the disposal and the 2nd sink basket.
  5. Basement_Lurker

    Basement_Lurker One who lurks

    Messages:
    668
    Location:
    Victoria, BC
    hmm, if you move the disposal to the right sink like you are wanting to do, you might have enough room to do a normal installation since you wouldn't be using that long sweep tee, but I doubt it.

    I guess you could dry fit this and see if it would work:

    move the disposal to the right sink, have both sinks drain into each side of a baffled tee, have the baffled tee branch drain down into the ptrap, and have the ptrap drain directly out into the wall without any fittings other than a coupling.
  6. Jay Mpls

    Jay Mpls Master plumber

    Messages:
    98
    Location:
    Minneapolis
    Doc,plan on opening the wall (make it nice and square so you can get a new piece of rock in.)and do it right!Terrys drawing should bring you home on this project.HOWEVER,
    If the other bowl in your sink is higher it all might work well if you cut right next to the coupling at the wall and go from there.Good luck!
  7. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,034
    Location:
    Cave Creek, Arizona
    drain

    The disposer is normally installed in the smaller/higher sink. Doing that, and it should be more of a change than the 1 1/2" you specify, and cleaning up the drain piping should help.
  8. nhmaster

    nhmaster Master Plumber

    Messages:
    3,189
    Location:
    S. Maine
    Another good picture for my collection of hack work. I'll offer no solution as you's guys have already pretty much nailed it.
  9. kingsotall

    kingsotall Plunger/TurdPuncher

    A lot of thought went into that mess and yet nothing good came of it. Best part is re-doing it can only be an improvement.
  10. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,034
    Location:
    Cave Creek, Arizona
    drain

    A lot of thought, and maybe many trips to Home Depot for advice and parts. Normally the "thoughts" would have been used BEFORE installing the cabinets and sink so the problem would not have occurred in the first place.
  11. doc_u

    doc_u New Member

    Messages:
    11
    Location:
    SF California
    After reading here for awhile, this is the option I have decided to attempt.

    I will saw off that hacked-up mess near the wall and attach a threaded fitting to it so I won't have to do THAT again.

    The main problem I forsee is that the waste outlet in the all will be directly behind the disposal.

    I will route it as suggested above, and see if this will work. If it doesn't, I'll probably open the wall and then call in a pro if the drain doesn't go straight down.

    Will provide more pictures of the dry-fit for further criticism.

    Thanks to everyone who posted so far. I appreciate your comments and suggestions.

    FYI - To the fellow who suggested that moving to the smaller bowl would increase the height of the disposal outlet more than the 1.25" I figured it would:
    You obviously weren't under MY sink with a tape measure. I have seen many sinks with the smaller bowl being MUCH shallower than the larger, but mine ain't one of 'em.

    Another option down the road may be to replace the whole sink with a single-bowl, which the wife and I may actually prefer, but that could prove problematic given the granite countertop, and is probably not going to happen right now due to cost.

    Thanks again.

    - Doc
Similar Threads: Kitchen drain
Forum Title Date
Plumbing Forum, Professional & DIY Advice Kitchen Sink Drain Oct 13, 2014
Plumbing Forum, Professional & DIY Advice Strange kitchen sink drain problem Sep 1, 2014
Plumbing Forum, Professional & DIY Advice is flexible drain kit appropriate for my kitchen sink? Aug 12, 2014
Plumbing Forum, Professional & DIY Advice Slow kitchen sink drain now backs up into the dishwasher. Jun 21, 2014
Plumbing Forum, Professional & DIY Advice new kitchen pipe slow draining Apr 18, 2014

Share This Page