Wall hung toilet installation issue (gerber 20-021)

Discussion in 'Toilet Forum discussions' started by mnoone, Nov 1, 2019.

  1. mnoone

    mnoone New Member

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    I am trying to replace a broken American Standard wall hung toilet from 1959. I purchased a Gerber maxell wall hung toilet (model 20-021) to replace it. The hole pattern appears to be the same between American Standard and Gerber. But the thing that is causing me issues is that the coupling coming out of the wall comes 5/8" out of the wall. The groove that it is supposed to fit into on the Maxwell toilet is 1/2" deep. So already there is 1/8" collision there. But there's supposed to be a neoprene gasket in between them. According to Zurn it should compress from 3/4" down to 1/2". So by my math you would want the coupling coming out of the wall to *not* come out of the wall, but instead be flush with the wall.

    So - I see a couple options:
    1. get a pile of washers and space toilet away from wall by 5/8".
    2. Use a dremel with a cutoff wheel and cut off 5/8" of the coupling sticking out of the wall. I'm worried that the remaining pipe might be too thin and would slice right through the neoprene gasket.
    3. Cut a sheet of 5/8" plywood to match the shape of the back of the toilet bowl, then cut holes in that and mount that to wall (ugliest route, but stronger than #2)

    I noticed that the coupling sticking out of the wall is threaded. So in theory I could just tighten the threads more and screw it 5/8" more into the wall - but I think the threads are rusted to all hell (being that they've been exposed to toilet water for the last 60 years) so I don't see that moving. Also I don't have a pipe wrench even close to big enough to fit around that coupling... I've included pictures below showing my predicament.

    Any ideas?

    IMG_20191101_121351.jpg IMG_20191101_121415.jpg IMG_20191101_121534.jpg IMG_20191101_121619.jpg IMG_20191101_121434.jpg
     
  2. Tuttles Revenge

    Tuttles Revenge In the Trades

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    The toilet doesnt or shouldn't actually rest against the wall, but on nuts and washers on the bolts. The bolts are much easier to adjust in and out than the drain barrel. But you may just need to place the nuts and washers out just a tad further than they were before to adjust the relative depth of the barrel to the toilet.
     
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  4. mnoone

    mnoone New Member

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    So is it acceptable to have 5/8" thick of washers on each bolt?

    Also - should I just be using normal galvanized washers or do I need something special? (brass, stainless, plastic, etc)
     
  5. Tuttles Revenge

    Tuttles Revenge In the Trades

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    These can get complicated and instructions must be followed very very carefully. The mounting nuts and washers must be perfectly plumb and flush to each other. There are good instructions for how this is done, I just cant find them currently...

    Make sure you have enough bolt to get the correct depth for the drain. You may have to replace the bolts if there isn't enough threads sticking through the toilet for the trim bolts. Sometimes there is extra bolt threaded into and past the carrier body in the wall but you have to loosen the locking nut to move the bolt. The hardware is 5/8" and the materials should be steel. The toilet should rest against washers backed up by 5/8" threaded nuts. Below is a diagram that shows what I think you have in the wall and shows the position of the mounting hardware. Your toilet may have come with instructions too.. but double check those to see if they're complete.

    https://www.zurn.com/media-library/web_documents/pdfs/specsheets/63136-pdf
     
  6. James Henry

    James Henry In the Trades

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  7. mnoone

    mnoone New Member

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    The nipple may be brass - it looked pretty decent, But the thing it was threaded into (that is mounted to my studs) looked rough. I can do more cleaning and see if that is actually true or not. But I think it was cast iron and chunks that fell off of it when I was cleaning it were definitely magnetic (verified with a magnet).
     
  8. mnoone

    mnoone New Member

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    So I'm not sure if this is clear or not - but my 4 bolts are just threaded rods that are threaded into something attached to the vertical cast iron drain pipe. So there is nothing directly behind them on the wall - there is the big mounting bracket maybe 4" behind the drywall. So I'm thinking a big stack of washers will just push through the 60 year old drywall. I'm definitely able to thread the threaded rods in more or less as needed (I think they're an extra inch or two long) so that's not an issue.

    What about putting a nut on the threaded rod and then putting some washers on that? That way the toilet would not be putting weight on the drywall at all.

    For what it's worth I still have one other similar toilet in my house (American Standard wall hung from 1959). It rests directly against the wall - no space between wall and back of it whatsoever.
     
  9. Tuttles Revenge

    Tuttles Revenge In the Trades

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    Yes, the washers need a backing nut to keep them in place. The zurn PDF diagram I linked to above shows that in the top down view.
     
  10. James Henry

    James Henry In the Trades

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    If you do decide to cut it, I would mark the nipple on the inside and take my time and cut it from the inside with the dremel .
    You have to consider that you will loose the wider lip that you cut off in the process. wall hung's are always finicky.
     
  11. mnoone

    mnoone New Member

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    OK interesting, this is different from how the old toilet was installed. The old toilet did not have backing nuts and was flush against the wall. So that way the load of it was spread across the wall, not just at the bolts. I don't think there was any wood immediately behind the drywall but the studs may have been just barely overlapping the toilet.

    Is there any chance that my mount is not strong enough to fully support the toilet and it is only strong enough for if the toilet is getting some support from the wall? Seems unlikely right?
     
  12. mnoone

    mnoone New Member

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    I'm really nervous to cut it due to loosing that wider lip. I'm using that as my last resort as I feel like that could end up causing much more extensive surgeries...
     
  13. Terry

    Terry Administrator Staff Member

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    The mount is strong enough.
    Normal installation is backing nuts with large washers. The bowl doesn't touch in most cases. I sometimes pick up four new 5/8 nuts at a hardware store in case the acorn nuts don't thread down far enough. The Gerber has a thinner edge where it's bolted on.

     
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  14. James Henry

    James Henry In the Trades

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    You have one more thing you can try before you do any of the suggestions we gave you earlier.
    Sometimes you can hang a toilet without making any modifications to it and it will fit and work without any problems.
    Hang the toilet, tighten the bolts like you would for a permanent installation and inspect the toilet.
    If the gap is too wide at the bottom then that's your call.
     
    Last edited: Nov 1, 2019
  15. Tuttles Revenge

    Tuttles Revenge In the Trades

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    Just a word of caution from experience hanging a toilet with the barrel sticking out too far.. if you can break the toilet if you tighten it up and the barrel busts thru.. But we already know you're worried about the depth of the barrel.. more a caution for anyone else. That dimension is important.
     
  16. James Henry

    James Henry In the Trades

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    On hundreds of wall hungs I've never seen that happen but I'll take your word for it.
     
  17. Tuttles Revenge

    Tuttles Revenge In the Trades

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    In the mid 90's I was running my first big project for the city of Seattle parks dept and they wrote themselves an exemption to the 1.6GPF rule so we were able to import 3.5gpf toilets from Canada... the same toilet.. except they had shallower depths for the drain barrell.. Fortunately only 1 was sacrificed in that manner.
     
  18. mnoone

    mnoone New Member

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    Hey folks - I ended up threading on some 5/8" nuts and fender washers onto all 4 posts. I tightened the bottom nuts until the fender washers were flush with the front of the waste coupling, checking for flush with a 36" level. I then tightened them another 3/4 of a turn or so. I then got the upper two nuts + washers to be perfectly vertically aligned with the bottom two using the 36" level again. Installed toilet, quickly hand threaded on some nuts + washers to hold toilet on, then used some pliers to hold on to the nuts behind the fender washers while I tightened the front nuts. (so that if the threaded rod moved, the nut would stay in place). I really wish I had put threadlock on the threaded rods both where they attach in the wall as well as on the nuts that sat behind the fender washers. Would have made this easier.

    Of course, since nothing is allowed to go smoothly - as soon as I hooked up water my water shutoff valve started leaking from the stem. I decided to replace the thing instead of tightening the packing nut. Got a shiny new quarter turn valve from the big orange store and no matter how tight I got it, it leaked from threads (and I used Teflon tape, mind you). Ended up mangling the thing so I went back to orange and grabbed another. That time I also used some pipe dope on it on top of the Teflon tape. That one didn't leak at all even when it was only semi tight. Replacing that thing in that tight space would have been a lot easier had I done it before installing the toilet.

    Anyway - everything seems to be working well now! Thank you all for your help!!

    IMG_20191102_184448.jpg
     
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  19. Tuttles Revenge

    Tuttles Revenge In the Trades

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    Right on. Thread locker is good for those bolts in the carrier. Typically they're installed with a locking nut on the face..

    Might want to make sure your extension cord is rated for the watts of the seat heater.
     
  20. Terry

    Terry Administrator Staff Member

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    835 Watts for the electrical on the Washlet.
     
  21. mnoone

    mnoone New Member

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    The extension is 16 AWG and 13A. So I think it's OK for 835W. Thanks for the concern!

    Yeah there were locking nuts on the face of the assembly in the wall - but I couldn't get at them to tighten them. I was able to reach through the floor from below and get one of the bottom two locking nuts tightened but couldn't reach any of the 3 others. Tried a couple ideas to get the remaining ones tight but had no luck. Should have just gotten thread lock but I think my technique of holding onto the other bolt was likely good enough.
     
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