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Need plumbing advice, please? [message #328427] Sun, 21 January 2018 08:09 Go to next message
GMC Jimmy is currently offline  GMC Jimmy   Canada
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Hello All, I hope everyone is enjoying this winter, it has been quite cold and snowy in most parts of North America... Ontario included.

1975 26' Coachmen built Royale with dry bath.

I'm working away on getting the GMC ready for the spring and was hoping to address an issue I noticed last autumn. While running the water in the front lounge sink (just happened to be this sink but it happens with the bathroom sink as well), after a couple of minutes I notice the water rises up from the shower drain and into the shower.

While trying to diagnose why this is happening, and I'm no plumber, you could hear some gurgling sounds as the water builds up into the shower.

Looking over the existing plumbing to determine drains and vents etc it appeared there isn't a direct drain vent, at least one that we could identify.

We tried snaking out lines, both drain and vent to try and clear any obstructions or clogs, did the best we could and because testing afterwards yielded the same result we looked at installing a new vent line. There is a vent line in the bathroom that ties the main drain line into a vent pipe but we thought it might fix the issue by adding another vent a bit further downstream towards the rear of the coach... no luck.

Here is a photo with a little description... http://www.gmcmhphotos.com/photos/my-75-royale/p64479-image350.html

A = the existing drain line from the front lounge sink past the bathroom which disappears into the floor next to the generator enclosure, assuming this goes to the grey tank?

B = the newly added vent line connecting the main drain to what I believe is the black tank vent.

C = the existing vent line from black tank up through the roof via the bathroom.

What am I missing here, the only other possibility I can think of is that there should be another vent somewhere direct from the grey tank to the atmosphere? If this is the case where should I be looking because I haven't seen one yet?

Or should I be chasing an obstruction somewhere?

As always your guidance is appreciated,
Regards,
Mike

Re: Need plumbing advice, please? [message #328430 is a reply to message #328427] Sun, 21 January 2018 08:39 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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What's the chance one of the tanks isn't draining properly?

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: [GMCnet] Need plumbing advice, please? [message #328433 is a reply to message #328430] Sun, 21 January 2018 09:28 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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If it’s backing up into the shower pan your holding tank must be full.
You should check your drain valve. It probably is broken so that when you pull the rod to drain the slide valve isn’t opening.
Or something is clogging the drain exit.
Perhaps someone has been dropping “wet naps” into the toilet?

Emery Stora
77 Kingsley
Frederick, CO

> On Jan 21, 2018, at 7:39 AM, Johnny Bridges via Gmclist wrote:
>
> What's the chance one of the tanks isn't draining properly?
>
> --johnny
> --
> 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> "I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
>
>
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Re: Need plumbing advice, please? [message #328434 is a reply to message #328430] Sun, 21 January 2018 09:43 Go to previous messageGo to next message
GMC Jimmy is currently offline  GMC Jimmy   Canada
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Johnny Bridges wrote on Sun, 21 January 2018 09:39
What's the chance one of the tanks isn't draining properly?

--johnny


Hi Johnny, this past summer I drained both tanks, there wasn't much in them except when I filled the grey water tank for testing, both showed no significant signs of slow drainage.
Thanks,
Mike
Re: [GMCnet] Need plumbing advice, please? [message #328436 is a reply to message #328433] Sun, 21 January 2018 09:48 Go to previous messageGo to next message
GMC Jimmy is currently offline  GMC Jimmy   Canada
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emerystora wrote on Sun, 21 January 2018 10:28
If it's backing up into the shower pan your holding tank must be full.
You should check your drain valve. It probably is broken so that when you pull the rod to drain the slide valve isn't opening.
Or something is clogging the drain exit.
Perhaps someone has been dropping "wet naps" into the toilet?

Emery Stora
77 Kingsley
Frederick, CO

> On Jan 21, 2018, at 7:39 AM, Johnny Bridges via Gmclist wrote:
>
> What's the chance one of the tanks isn't draining properly?
>
> --johnny
> --
> 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> "I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
>
>
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Hello Emery, I purchased the coach in October of 2016 and nobody has been using the toilet since I have owned it. I did a renovation and removed and replaced the toilet during last winter.

I did drain both tanks this past summer and as mentioned above I never noticed any slow drainage, even when I filled the grey tank and drained it, it appeared to drain well. I have no previous history or knowledge of what it should drain like but it seemed to flow quite well.

Thanks,
Mike
Re: Need plumbing advice, please? [message #328437 is a reply to message #328427] Sun, 21 January 2018 09:49 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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I dont think this is a common problem, so I would be looking for a clogged or broken pipe. But i do not lnow anything about your plumbing as i have never worked on your floorplan.

Does it eventually drain down in the shower after time. Or does it backup and stay backed up??

Snake camera time??



Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: Need plumbing advice, please? [message #328438 is a reply to message #328427] Sun, 21 January 2018 09:50 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Other question.

Does the shower drain ok? Is it onlt the sink? If you pour water into showe does it go into sink??



Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: [GMCnet] Need plumbing advice, please? [message #328444 is a reply to message #328438] Sun, 21 January 2018 13:17 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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On Sun, Jan 21, 2018 at 7:51 AM Jon Roche wrote:

> Other question.
>
> Does the shower drain ok? Is it onlt the sink? If you pour water into
> showe does it go into sink??
>
> You might snake from the shower as it leads to your gray tank on your Royal
> --
> Jon Roche
> 75 palm beach
> St. Cloud, MN
> http://lqqkatjon.blogspot.com/
>
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--
Jim Kanomata
Applied/GMC, Newark,CA
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: Need plumbing advice, please? [message #328464 is a reply to message #328437] Sun, 21 January 2018 18:20 Go to previous messageGo to next message
GMC Jimmy is currently offline  GMC Jimmy   Canada
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lqqkatjon wrote on Sun, 21 January 2018 10:49
I dont think this is a common problem, so I would be looking for a clogged or broken pipe. But i do not lnow anything about your plumbing as i have never worked on your floorplan.

Does it eventually drain down in the shower after time. Or does it backup and stay backed up??

Snake camera time??



Hi Jon, it drains from the shower, doesn't take long just a few gurgles and drains down, maybe 20 seconds or so.
Regards,
Mike
Re: Need plumbing advice, please? [message #328465 is a reply to message #328438] Sun, 21 January 2018 18:26 Go to previous messageGo to next message
GMC Jimmy is currently offline  GMC Jimmy   Canada
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lqqkatjon wrote on Sun, 21 January 2018 10:50
Other question.

Does the shower drain ok? Is it onlt the sink? If you pour water into showe does it go into sink??



If I pour water down the shower drain sufficient to create the back up it does drain. The water does not back up high enough to reach the sink, the shower drain is much lower than the sink, in order to allow sufficient water to potentially reach the sink I assume the water would overflow out of the shower enclosure and onto the coach floor.

Hope this makes sense.,
Mike
Re: [GMCnet] Need plumbing advice, please? [message #328466 is a reply to message #328444] Sun, 21 January 2018 18:29 Go to previous messageGo to next message
GMC Jimmy is currently offline  GMC Jimmy   Canada
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jimk wrote on Sun, 21 January 2018 14:17
On Sun, Jan 21, 2018 at 7:51 AM Jon Roche wrote:

> Other question.
>
> Does the shower drain ok? Is it onlt the sink? If you pour water into
> showe does it go into sink??
>
> You might snake from the shower as it leads to your gray tank on your Royal
> --
> Jon Roche
> 75 palm beach
> St. Cloud, MN
> http://lqqkatjon.blogspot.com/
>
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--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Hi Jim, sorry but there wasn't a message, just what's quoted above?
Mike

Re: [GMCnet] Need plumbing advice, please? [message #328467 is a reply to message #328465] Sun, 21 January 2018 18:37 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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When you say "pour water down the shower drain sufficient to create the
back up", how much water is that? If it's less than 25-30 gallons (the
gray water tank capacity), the tank's not empty
and you've found your problem.


Ken H.


On Sun, Jan 21, 2018 at 7:26 PM, Mike wrote:
>
> lqqkatjon wrote on Sun, 21 January 2018 10:50
>> Other question.
>>
>> Does the shower drain ok? Is it onlt the sink? If you pour water into
showe does it go into sink??
>
>
> If I pour water down the shower drain sufficient to create the back up it
does drain. The water does not back up high enough to reach the sink, the
> shower drain is much lower than the sink, in order to allow sufficient
water to potentially reach the sink I assume the water would overflow out
of
> the shower enclosure and onto the coach floor.
>
> Hope this makes sense.,
> Mike
>
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Need plumbing advice, please? [message #328468 is a reply to message #328467] Sun, 21 January 2018 18:47 Go to previous messageGo to next message
77Royale   United States
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Location: Mid Michigan
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Is it possible that where the coach is, when the water is backing up is not level? In my rear bath royale, the tub backed up once. The grey tank which is separate was near full, but I was also out of level with the back end a bit higher than the front. as soon as I aired the bags down a bit the issue was resolved. There may not be much if any "run" in the drains if your shower drain is in the middle of the coach and your trying to send water lower to the rearward grey tank.

77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy. Mid Michigan
Re: [GMCnet] Need plumbing advice, please? [message #328479 is a reply to message #328464] Sun, 21 January 2018 21:35 Go to previous messageGo to next message
Dave Stragand is currently offline  Dave Stragand   United States
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Does the gray tank have a clogged atmospheric vent? If air can’t get out, new water can’t get in too easily.

> On Jan 21, 2018, at 7:21 PM, Mike wrote:
>
> lqqkatjon wrote on Sun, 21 January 2018 10:49
>> I dont think this is a common problem, so I would be looking for a clogged or broken pipe. But i do not lnow anything about your plumbing as i
>> have never worked on your floorplan.
>>
>> Does it eventually drain down in the shower after time. Or does it backup and stay backed up??
>>
>> Snake camera time??
>
>
> Hi Jon, it drains from the shower, doesn't take long just a few gurgles and drains down, maybe 20 seconds or so.
> Regards,
> Mike
>
>
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1978 Transmode (403) Pittsburgh, PA
Re: [GMCnet] Need plumbing advice, please? [message #328483 is a reply to message #328479] Mon, 22 January 2018 00:36 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Take a snake at the shower as it will lead to the tank.

On Sun, Jan 21, 2018 at 7:35 PM, Dave Stragand <
dave.stragand@forwardlook.net> wrote:

> Does the gray tank have a clogged atmospheric vent? If air can’t get out,
> new water can’t get in too easily.
>
>> On Jan 21, 2018, at 7:21 PM, Mike wrote:
>>
>> lqqkatjon wrote on Sun, 21 January 2018 10:49
>>> I dont think this is a common problem, so I would be looking for a
> clogged or broken pipe. But i do not lnow anything about your plumbing as i
>>> have never worked on your floorplan.
>>>
>>> Does it eventually drain down in the shower after time. Or does it
> backup and stay backed up??
>>>
>>> Snake camera time??
>>
>>
>> Hi Jon, it drains from the shower, doesn't take long just a few gurgles
> and drains down, maybe 20 seconds or so.
>> Regards,
>> Mike
>>
>>
>> _______________________________________________
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--
Jim Kanomata
Applied/GMC, Newark,CA
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http://www.appliedgmc.com
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Need plumbing advice, please? [message #328504 is a reply to message #328483] Mon, 22 January 2018 13:23 Go to previous messageGo to next message
GMC Jimmy is currently offline  GMC Jimmy   Canada
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Thanks again,

Ken... just a few gallons is all it takes to begin creeping into the shower, certainly less than the tank capacity.

If I "think" I have emptied the tank and it's not really empty this could be a/the reason.

I have filled the new water tank to approximately 50% capacity and drained it, water appeared to have good flow, I did this in the fall.

Perhaps it's time to snake the drains again in an attempt to address this issue.


77 Royale... the coach is on a flat concrete floor in my shop, however, the rear could probably be raised a bit as it does look a little low.

Dave... good question, I have added another vent from the main drain to an existing vent which I believe to be the black tank vent. I don't believe there is a direct vent from the grey tank to the atmosphere... should there be a dedicated vent from the grey tank to the atmosphere?

Thanks for the input,
Mike
Re: [GMCnet] Need plumbing advice, please? [message #328510 is a reply to message #328504] Mon, 22 January 2018 18:03 Go to previous messageGo to next message
palerider is currently offline  palerider   United States
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Member
once upon a time when I was younger and a whole lot less experienced. The first trip or two I would just park, hook-up the drain hoses , open the valves and go about our business. I noticed after a couple of trips, liquid would back up in the tub in a very short while. After talking with folks a lot smarter than me, I found that that was a no-no.. The liquid will drain and leave the solids causing the black tank to sludge up. Very hard to clean out after sitting all winter. I filled the tanks with a caustic soap solution and let it set for a bit, drained, repeated several times even using a pressure washer. Finally gotter dun but it was a chore. Could that be your problem also?.....Tom
Re: [GMCnet] Need plumbing advice, please? [message #328513 is a reply to message #328510] Mon, 22 January 2018 18:46 Go to previous messageGo to next message
Justin Brady is currently offline  Justin Brady   United States
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My guess is tank venting as well.
The water displaces the air in the tank, if the air can't escape the water can't get in.

Most tanks have at least one vent straight to atmosphere through the roof. Not sure of the grey setup on your coach though as I don't have a grey tank!


Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
Re: [GMCnet] Need plumbing advice, please? [message #328514 is a reply to message #328513] Mon, 22 January 2018 18:48 Go to previous messageGo to next message
Dave Stragand is currently offline  Dave Stragand   United States
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An easy test might be to open the gray tank dump valve -- allowing water/air out -- then try draining the sink.

-----Original Message-----
From: Gmclist on behalf of Justin Brady
Sent: Mon 1/22/2018 7:46 PM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Need plumbing advice, please?

My guess is tank venting as well.
The water displaces the air in the tank, if the air can't escape the water can't get in.

Most tanks have at least one vent straight to atmosphere through the roof. Not sure of the grey setup on your coach though as I don't have a grey
tank!
--
Justin Brady
http://www.thegmcrv.com/
1976 Palm Beach 455

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1978 Transmode (403) Pittsburgh, PA
Re: [GMCnet] Need plumbing advice, please? [message #328518 is a reply to message #328513] Mon, 22 January 2018 19:46 Go to previous messageGo to previous message
Ken Henderson is currently offline  Ken Henderson   United States
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Justin, et al,

I don't see how venting can possibly be the problem. To run into the
shower pan, there MUST be liquid up to that level. H20 being a bit heavier
than air, even if the tank had no vent (which it apparently now has two of,
the original and the newly added one), the water would STILL go to the
bottom of the tank, not up into the shower. Admittedly increased pressure
in the tank MIGHT force a little bit, maybe a cup full, of water out of the
P-trap, but no more.

Ken H.



On Mon, Jan 22, 2018 at 7:46 PM, Justin Brady wrote:

> My guess is tank venting as well.
> The water displaces the air in the tank, if the air can't escape the water
> can't get in.
>
> Most tanks have at least one vent straight to atmosphere through the roof.
> Not sure of the grey setup on your coach though as I don't have a grey
> tank!
> --
> Justin Brady
> http://www.thegmcrv.com/
> 1976 Palm Beach 455
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
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