Black tank replacement

S

skip hartline

Member
Sep 9, 2011
518
5
18
Evening all,
Finally decided to replace the black tank on my 74 Canyonlands, I suspected it had problems so the other day I filled it up to just where the shower
drain was going to overflow and went outside and could see Niagra Falls running off the top. I know it could be just seals at the bath hook up but
think it's time, with the mess of Silicone that has been put on the first valve, worried that the next time I have to close that one to work on the
Macerator its going to start leaking and the one behind the tee is just about completely frozen to the point I don't think I could dump it with stinky
slinky if I had to. I have searched in all the photo files and through the forum search and have not found a really concise description on to exactly
go about it, just bits and pieces and how to handle common issues no step by step. If anyone knows of a paper or presentation that is out there or
have any hints I'd really like to hear about them. Located tanks at Sirrums in Okeechobee and they are drilled or undrilled, that's a good question.
Another question would be to get to the rear sink and shower connector on the back of the tank do you go at through the area in front of the water
tank? What other parts and pieces will be needed to get this accomplished, replacing both valves is a given. Any and all ideals will be welcome.
Thanks.
Skip Hartline

--
74 Canyon Lands, FiTech,
3.7 FD, Manny Tranny,
Springfield Distributor,
2001 Chevy Tracker Ragtop Towd
 
Are you thinking about installing a new tank, or replacing yours with an
old one from a similar model of coach?
When I last worked on a in-use black tank, and dealt with that stinky
unsanitary mess, I vowed to never work on another tank that was in use.
I take a sawzall, and cut all the pipes, disconnect and label the
wires, and remove the toilet. Then I lower the old tank, duct tape closed
all the openings, and put it in the back of my pickup for a trip to the
landfill.
Then I temporarily install the new tank, mark where the pipes enter
it, and remove it and cut all the holes with hole saws . Then, put it back
in place. Hook up all the pipes, and that's about it. Wear gloves, and a
good respirator, and safety glasses.
That's how I do it, when I can't get out of it.
Jim Hupy
Salem, Oregon

> Evening all,
> Finally decided to replace the black tank on my 74 Canyonlands, I
> suspected it had problems so the other day I filled it up to just where the
> shower
> drain was going to overflow and went outside and could see Niagra Falls
> running off the top. I know it could be just seals at the bath hook up but
> think it's time, with the mess of Silicone that has been put on the first
> valve, worried that the next time I have to close that one to work on the
> Macerator its going to start leaking and the one behind the tee is just
> about completely frozen to the point I don't think I could dump it with
> stinky
> slinky if I had to. I have searched in all the photo files and through the
> forum search and have not found a really concise description on to exactly
> go about it, just bits and pieces and how to handle common issues no step
> by step. If anyone knows of a paper or presentation that is out there or
> have any hints I'd really like to hear about them. Located tanks at
> Sirrums in Okeechobee and they are drilled or undrilled, that's a good
> question.
> Another question would be to get to the rear sink and shower connector on
> the back of the tank do you go at through the area in front of the water
> tank? What other parts and pieces will be needed to get this accomplished,
> replacing both valves is a given. Any and all ideals will be welcome.
> Thanks.
> Skip Hartline
>
> --
> 74 Canyon Lands, FiTech,
> 3.7 FD, Manny Tranny,
> Springfield Distributor,
> 2001 Chevy Tracker Ragtop Towd
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
 
No going to buy a new one
--
74 Canyon Lands, FiTech,
3.7 FD, Manny Tranny,
Springfield Distributor,
2001 Chevy Tracker Ragtop Towd
 
Skip,
when you get a new one from us, Nick or I can give all the information and
parts you need as we have done many.

On Tue, Jan 18, 2022 at 4:44 PM Skip Hartline
wrote:

> No going to buy a new one
> --
> 74 Canyon Lands, FiTech,
> 3.7 FD, Manny Tranny,
> Springfield Distributor,
> 2001 Chevy Tracker Ragtop Towd
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

--
Jim Kanomata ASE
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
 
Skip,

Talk to your favorite GMC supplier and see about getting the replacement tank with the fitting where they belong.

If you have the option, order the tank for the Valterra (not Thetford) dump valve. They are as problem free as the OE and cost 1/3.

To remove the tank, remove the pot and unscrew the flange. It will come out with a length of pipe.
In the back bedroom, you will have to take out the water tank to access the sink and shower drains.
The galley sink drain connection is (if it is a 26) under the floor of the closet.
Both of the smaller drains are steel pipe and that may be your problem. It also may be worse because the steel is gone except in the threads you will
want to reuse. It takes either a pair of the new push button Channel Locks or Monster basin wrench to work those.

Mine had iron pipe in there that had expended and cracked the tank top fitting for the smaller drains.

Best of luck....

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
The new tanks are designed to use the Veltra Valve assy.

> 75 palm beach is fairly close to your 74 canyon lands.
>
> Here is my write up:
>
> http://lqqkatjon.blogspot.com/2014/05/new-black-tank-install.html?m=1
> --
> Jon Roche
> 75 palm beach
> EBL EFI, manny headers, Micro Level, rebuilt most of coach now.
> St. Cloud, MN
> http://lqqkatjon.blogspot.com/
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

--
Jim Kanomata ASE
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
 
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