Holding tank replacement or repair

S

scott nutter1

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Jan 5, 2015
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I noticed I have a small/medium leak in my black water tank. It is a 78 Royale Center Kitchen. This unit has 2 separate waste tanks (black water and
gray water).
I have read post where plastic welding would be the preferred method of repair. But being the original tanks, maybe it's time to replace?
Couple of questions on replacement,,,,
1. Should I just go with a large single tank?
2. If I replace both tanks, will they come already cut/drilled for the sinks, shower, and toilet?
Thanks, Scott.
--
Scott Nutter
1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final drive, Quad bags, tankless water heater, everything Lenzi. Alex Ferrera
installed MSD Atomic EFI
Houston, Texas
 
Hi Scott,

I recently parked my coach for the winter over the top of one of those concrete parking slabs. When the air in the bags went down it lowered the
black tank down right on top of it. I patched it up using this kit and a little bit of fiberglass cloth.
https://www.amazon.com/West-System-Epoxy-Adhesive-Repair/dp/B002IZBM4I

Patch is strong, leak free, and I am really happy with the results. While I was under there I noticed that PO had done a similar patch on the same
crack. It had lasted at lest 5 years and would have gone longer if not for my unfortunate parking job. Before I patched mine I read a lot threads
advising to bite the bullet and get a new tank. Now I think of it like this. Somewhere out there right now is a rock/ speed bump / retread / antler
with your black tanks name on it. If it busts a hole in the one you spent $400 and a whole day installing its a tragedy. If it busts open the one with
$25 patch job you just shrug and pull out the unused part of the patch kit. Your cost per snakebit black tank is now down to $12.50.

--Tim
--
Tim Taylor
Austin TX
76 Birchaven (SB)
76 Triumph TR6
 
Scott,
I
I wouldn't even THINK about replacing the gray and black water tanks with a
gray+black tank! Without even considering that it would be much more
difficult than replacing them individually. I simply know that over the
past 60+ years of RVing, I've never had reliable level indication until the
gray water appeared in the bathtub. Thank goodness it's never been
combined water! :-)

Since it's been over 20 years since I replaced both tanks in the
X-Birchaven, I don't remember whether the hidden deterioration justified
the effort.

Ken H.

On Sat, May 18, 2019 at 6:26 PM Scott Nutter via Gmclist <

> I noticed I have a small/medium leak in my black water tank. It is a 78
> Royale Center Kitchen. This unit has 2 separate waste tanks (black water and
> gray water).
> I have read post where plastic welding would be the preferred method of
> repair. But being the original tanks, maybe it's time to replace?
> Couple of questions on replacement,,,,
> 1. Should I just go with a large single tank?
> 2. If I replace both tanks, will they come already cut/drilled for the
> sinks, shower, and toilet?
> Thanks, Scott.
> --
> Scott Nutter
> 1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final
> drive, Quad bags, tankless water heater, everything Lenzi. Alex Ferrera
> installed MSD Atomic EFI
> Houston, Texas
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
> I noticed I have a small/medium leak in my black water tank. It is a 78 Royale Center Kitchen. This unit has 2 separate waste tanks (black water
> and gray water).
> I have read post where plastic welding would be the preferred method of repair. But being the original tanks, maybe it's time to replace?
> Couple of questions on replacement,,,,
> 1. Should I just go with a large single tank?
> 2. If I replace both tanks, will they come already cut/drilled for the sinks, shower, and toilet?
> Thanks, Scott.

Scott,

If you order the tank from JimK, you might be able to get one that is ready to install. Otherwise, I think it would be a slim bet.

Welding may be the preferred method of repair, but the tank is either polypropylene or polyethylene and this is not something that is likely to be
successfully welded at home and for sure, not in place. I know, I used to weld it when I worked at Thetford about a lifetime ago. I tried it on my
own black tank and ended up taking the tank to a plastic shop for repair. (Twice, but that is a story in its own.) This was before G-Flex.

The kit Tim called out is not normal epoxy. It is West Systems G-Flex. This is an epoxy that is flexible when cured. It will still require that you
"flame treat" the area that needs to have the epoxy bond to it. This is an interesting process. It requires that you run the flame of a propane
torch over the area. This changes the surface of the tank material to something that is not poly-whatsit but that material is still part of the tank.


We had a demonstration of this material and process at an international a while back.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
My 1978 Coachmen Royale has ABS tanks which are easier to repair with proper ABS supplies than the poly whateversomething the GMC upfits have.
--
1975 Glenbrook, 1978 Royale rear bath
Raleigh, NC
 
My Norris 23' didn't even have gauges. You could see the end of the water tank in a closet and the black and fresh tanks were the same size. When
the supply gets low, go dump. Keeps it out of the tub. Propane had a gauge on the tank, no remote.

--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
 
Scott,
Sice you have two seperate tank, keep it that way.
Flush the black first and followup with gray.
Regular RV are set up with two tanks.
Repairing the tank is lot easier than installing a new. We do sell them,
but hate to see people spend time if it is not necessary.

On Mon, May 20, 2019 at 8:33 AM Jon Roche via Gmclist <

> just fyi- single replacement tank is not that large. I am pretty sure
> my oem was 35 gallon, the new one I installed is 30 gallon.
>
>
> I have seen the same number of tanks repaired that leak, that no longer
> leak. all varies on repair methods used and the person doing the repair.
>
>
> --
> Jon Roche
> 75 palm beach
> St. Cloud, MN
> http://lqqkatjon.blogspot.com/
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
Thanks all,
I think the smart money goes to Tim's repair kit via Amazon. It stays flexible and works on all tanks.
I'll just keep repairing till the tank becomes unrepairable. Then replace.
Scott.
--
Scott Nutter
1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final drive, Quad bags, tankless water heater, everything Lenzi. Alex Ferrera
installed MSD Atomic EFI
Houston, Texas
 
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