Thetford valve issue/repair. 2 part question

[John_Joey]

My black tank valve seems to have debris in it stopping it from fully closing. For the time being I put a temp valve at the end of the line, but it has created it's own issues and it's time to fix the problem.

Both gray and black tank each go to a Thetford valve which then is directly tied to a Y pipe. The Thetford valves appear to be glued in place which strikes me as the dumbest thing to do.

So the first question is has anyone run into this? Below is a picture of the valve. I believe I have 08671 (or 08667 I'll look tomorrow for a part number on it.) Is that valve truly glued on?

Second question is if it is glued in the only way I can see fixing the blockage is cutting out the valves and Y pipe with short stubs, fishing out the blockage, then using three 3 inch rubber couplers reattach it. Anybody see any problems with that, or have a better way of doing it?

[John_Joey]

Chris Bryant wrote:
Cutting and repairing with a no hub coupler (rubber) is the factory method for Airstream. Can you not access the screws holding the valve together?

Thanks for taking the time Chris (and Doug also.)

If you're talking about the 7+ screws then yes, I can access them, but there is no room to separate the two parts. Everything is an exact fit and is glued in place.

I am dumbfounded on this one. What I can figure, I have two options at this point. Option one; is to cut all of it out and repair it on the picnic table and use rubber couplings to put it back in. Option two is to just re-plumb the whole thing with Valterra valves. Both options kinda spook me since if anything goes wrong DW & me would be living in a rig with no septic until I can figured out plan B.

I would hire the job out, but due to our location I'm sure I would do a better job, and would not screw it up leaving us stranded. Hiring it out "may" leave us waiting on local talent and parts for days/weeks/months. So I need a plan of attack, and maybe a plan B if I run into problems. Any help/ideas is much appreciated.

[gotsmart]

John&Joey wrote:
Guessing cutting it all out and using rubber couplers is my only option unless someone out there has a better idea. We're currently snow birding in the rig for the winter which makes it a tougher job.

If I cut it all out and it doesn't go as plan the rig becomes unlivable till I figure out a plan B.

If you were to install Valterra valves, I would recommend taking the RV to a service center. Let them own the problem. The tolerances for the Valterra valve to fit properly have to be spot on.

All this assumes that you want to be able to replace a valve by yourself in the future. Below is my black valve. To the left is the "Y", and on the other side of the "Y" is the gray valve.

I keep spare valves. They are easy enough to change out, but I would not want to be the one to do the initial assembly to make the "Y" line up perfectly between the valves.

[Chris_Bryant]

Cutting and repairing with a no hub coupler (rubber) is the factory method for Airstream. Can you not access the screws holding the valve together?

[John_Joey]

dougrainer wrote:
http://www.adventurerv.net/thetford-repair-package-for-plastic-side-valve-p-5138.html?gclid=CN-qv7yi...

This is the rebuild kit. Unless you have BROKEN parts, you just rebuild Thetford dump valves. Doug

Turns out I have the 08671 valve which means both ends are glued in place. This is on a Travel Supreme 5th wheel and all of the connections from the tanks to the hose attach are glued. There is no way to break it apart anywhere (no bolts or slip connections.) Which is the second part of the questions. Both valves are glued to a Y joint. Opposite ends are glued to a pipe to the tanks. How in the world do I go about repairing something like that? Best I can come up with is cut the pipes between the tanks and valves then use rubber couplers to reattached. Kinda nervous about doing that since there really is no going back. Any ideas or words of advice?

[dougrainer]

http://www.adventurerv.net/thetford-repair-package-for-plastic-side-valve-p-5138.html?gclid=CN-qv7yi...

This is the rebuild kit. Unless you have BROKEN parts, you just rebuild Thetford dump valves. Doug

[John_Joey]

Guessing cutting it all out and using rubber couplers is my only option unless someone out there has a better idea. We're currently snow birding in the rig for the winter which makes it a tougher job.

If I cut it all out and it doesn't go as plan the rig becomes unlivable till I figure out a plan B.

[wrgrs50s]

Sorry about that. I see now that info on changing the thetford valves is hard to find. The only info I found was on replacing the valves on an airstream trailer and it shows that they all have 4 screws that attach them directly to a flange on the tank. If I'm understanding correctly, the valve that has a collar on both sides, one side is glued to the down pipe as you suspect, and the other side is a slip joint with a rubber seal that is pulled together at the bottom of the tank by the 4 screws into the flange on the tank. The 4 screws may be difficult to see or to get to.

If this is the case, to replace it would require you to cut the down pipe and use a rubber clamp joint to reassemble with a new valve.

Not sure if any of this info fits your application without having my eyes on it, but if anything else, just food for thought.

[John_Joey]

wrgrs50s wrote:
Search youtube.com for videos of how to change the black tank dump valve. Almost anything you would like to know concerning rv's is on youtube.

That was a very good thought, but they all deal with Valterra valves. These are Thetford's that appears to be glued directly to the waste pipes. No bolts are present for a simple replacement like with a Valterra.

[wrgrs50s]

Search youtube.com for videos of how to change the black tank dump valve. Almost anything you would like to know concerning rv's is on youtube.

[dougrainer]

Thetford valves have screws to take the valve apart. Thetford sells rebuild kits with the seals and gaskets. Doug