how to connect cast iron to pvc in a vertical run

Discussion in 'Plumbing Forum, Professional & DIY Advice, Tips & ' started by bbsux, Dec 2, 2008.

  1. bbsux

    bbsux Custodian

    Messages:
    23
    Location:
    Lincoln NE
    I have a vertical section of 4" cast in my house that needs replaced. We pulled out the cast with the breaker and there was no option to keep the old hub (due to the builders lack of planning). We have used a couple different of fernco no hub straps (we have used the proflex and the 1056 4" to 4". We finally took the big metal strap off the proflex and put it on the 1056, and it holds the BEST)

    But the darn thing just keeps leaking (well not much, but enough to make me want to fix it.)

    Is there a different way to do this?
  2. Gary Swart

    Gary Swart In the Trades

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    Yakima WA
    I'm not too sure what you are using. You say "Fernco" and then say "no hub" and this leads me to think perhaps you are confused about what you are using. If you are using a neoprene sleeve with hose clamps on each end, you are using the wrong product. What you should be using is a true no-hub which has a sleeve but that is entirely covered with a stainless steel clamp from end to end. These may also be made by the Fernco company, but usually when we say Fernco, we mean the sleeve with just 2 hose clamps. These are OK for underground use, but no for above ground. They do not provide enough ridge support to the two pipes.
  3. Redwood

    Redwood Master Plumber

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    You have bastardized the coupling.
    You are using an illegal above ground all rubber with 2 hose clamps Fernco and removed the band and clamps of the proflex which would be a legal coupling to use to put on the illegal coupling. They are 2 different widths small wonder its leaking!
  4. bbsux

    bbsux Custodian

    Messages:
    23
    Location:
    Lincoln NE
    Umm, it was leaking worse BEFORE I changed this. It is leaking MUCH less now.

    And they are 2 different widths, but the band and clamps fit right in the center portion of the fernco and when all four clamps and the band are used its much better...

    Lets see -- use "legal coupler" and have it leak worse....
    or
    use combination of band and clamps and 2 other hose clamps to decrease leaking...

    Maybe you'd be fine with it leaking BUT I'M NOT!!!
    Last edited: Dec 3, 2008
  5. bbsux

    bbsux Custodian

    Messages:
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    Location:
    Lincoln NE
    excuse me, for not knowing "the lingo". Its a sleeve, with a ridge in the center covered by a band and strap... you want the serial and part number too? I was under the impression that when people post here their questions are answered. Are they insulted instead?

    Umm, I would have thought plumbers would know that if you don't have a hub, then your gonna have to connect pipe to pipe as opposed to pipe to hub or hub to hub.

    I am basically using both, with the clamp cover off the proflex and the two from the fernco.
  6. Redwood

    Redwood Master Plumber

    Messages:
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    Location:
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    Then you are not using the right size coupling or, there is an irregularity in the cast that needs to be ground smooth.

    Another possibility is that the cast has a crack in it that is leaking.
  7. bbsux

    bbsux Custodian

    Messages:
    23
    Location:
    Lincoln NE
    Well for one thing the cast was "cast" uneven. The pipe wall nearest to the wall is horribly thin while the other side is over twice as thick. I could see a little irregular and maybe some internal rusting away.....

    So on the thin side I am understandably hesitant to break too much of the pipe to get a clean edge and its a little irregular.

    I'm beginning to wonder if i could put a pvc 4" to 3" reducer (putting the 3" pipe several inches down into the cast iron and putting a coupling on it ...

    How much would that reduce the flow?
  8. Gary Swart

    Gary Swart In the Trades

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    Location:
    Yakima WA
    Pal, if I wanted to insult you, I would have said something like this. "You obviously don't have a clue about what you're doing, so call a plumber to do this right instead of continuing to do a hack job." But, since I didn't want to insult you, I tried to explain the difference in what you apparently are trying to use and what you should be using. You might want to try contacting Southern Man, he has lots of ways of doing things.:rolleyes:
  9. Redwood

    Redwood Master Plumber

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    Location:
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    For some reason he hasn't been around in a few weeks...:cool:
  10. Gary Swart

    Gary Swart In the Trades

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    Location:
    Yakima WA
    Hmmm, I wonder why?
  11. Redwood

    Redwood Master Plumber

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    Brought a knife to a gunfight?:eek:
  12. kingsotall

    kingsotall Plunger/TurdPuncher

    I didn't see any insulting dialogue in your reply, Gary.

    Definitely don't start reducing the pipe in order to get rid of a leak. How do you know that you have tightened down fully on the no-hub¿ To do the job properly I suggest getting a titty wrench... ahem... a 5/16 torque wrench meant for no hubs that are set for 60 lbs of pressure. Re-dress the original shielded no-hub and see what the results are.
  13. bbsux

    bbsux Custodian

    Messages:
    23
    Location:
    Lincoln NE
    Gary, I want to apologize. I was angry when I read your response and read more into it than was there.

    Actually, I went back last night to check on it and the leak has totally stopped. (this is with the fernco coupler with the proflex sleeve in the center)

    I understand about the little ledge in the coupler that is supposed to provide support for the two pipes.. But the PVC section on top doesn't actually rest on top of it like the old cast iron did. It was basically resting on it with all the weight from the roof down (2 stories with attic of 4 inch cast). But we have the new stuff anchored and attached in 8 or nine places so the stuff in the basement is pretty much static.

    If it was just like the old stuff (all that weight) I'd never think of not using the proflex coupling.

    Anyways here's a teaser... They used to cut a hole in the side and weld or braze to make sanitary t's or y's. Did they also cut a pipe off to make a sanitary t? I dug dirt out down below and found a new sanitary t and it looks like they cut the pipe off, then trimmed the side to add the new connector with a saddle type connection, they they welded the whole way around.

    The problem is that the weld has pin leaks and I'm unsure what to do...

    Do I use some "waterweld" (from jb weld, sets up underwater if need be, sets in 20 minutes and cures in a couple of hours) and add to the weld temporarily until I can spend the time to cut the piece out a replace it with pvc (I need to just cut it all out until it changes to clay)?

    Thanks
  14. Gary Swart

    Gary Swart In the Trades

    Messages:
    7,347
    Location:
    Yakima WA
    No need to apologize. I sometimes get a little terse in my off-the-cuff writing and come across as a smart ass.:eek: As far as the current question, I really don't have much advice, but a couple of things you said caught my attention. You said the previous pipes had been "welded". Cast iron requires a very special kind of welding which to my limited knowledge is not a normal part of plumbing cast iron drains.:confused: Then you ask about using epoxy (and JB Weld is just epoxy) I suppose for a very temporary patch job you could try it, it would be a step up from duct tape, but I would not trust it to hold for long, if indeed it would hold at all.
  15. bbsux

    bbsux Custodian

    Messages:
    23
    Location:
    Lincoln NE
    Oh yeah, I don't expect it to hold for long -- just until I can get everything lined up to do it...


    Then the plumbers that did my house didn't know what they were doing... It looks like they cut a hole and welded on a piece where ever they needed to... I swear the the cast iron I took out (I replaced from the attic down to waist high in basement with pvc) had at least 10 places where they did that.
  16. Terry

    Terry Administrator Staff Member

    Messages:
    15,000
    Location:
    Bothell, Washington
    If you have old cast iron pipe that is 4-1/8" OD and you want to join to newer pipe, most of that is 4-3/8", you have two different sizes.

    For that combination, I use a copper by cast iron no-hub coupling.
  17. bbsux

    bbsux Custodian

    Messages:
    23
    Location:
    Lincoln NE
    That must be a specialty item can't find it anywhere local here -- even the plumbing shops...

    Anyplace online? Thanks...
  18. Terry

    Terry Administrator Staff Member

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    15,000
    Location:
    Bothell, Washington
    Last edited: Dec 5, 2008
  19. bbsux

    bbsux Custodian

    Messages:
    23
    Location:
    Lincoln NE
  20. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

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    21,995
    Location:
    New England
    The ones you likely find generally available, are sized for the same pipe on each side. The one specified has different diameters on one side ot the other so it can provide the proper seal.
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