?? for those with dump valve leaks. 😳

[ROBERT CROSS]

....anyone have an external leak, not thru the discharge but out the tank cover drain holes?
This past Spring get-ready I noticed a small leak after filling the grey tank with 5gal.
Could there be a seal leak at the slide housing that would leak externally into the pan?
POI...the slide operates smoothly without binding.

Bob
🇺🇸

[Bill M.]

I have not had such a leak. The valves on my trailer are screwed to a mount that is held on to the tank outlet by a clamp. So there are 2 sources for such a leak. Thr seal between the valve mount and the tank and the seal between the valve and the valve mount. In addition one of my valve bodies had small cracks in it. I think cutting an inspection port may be in your near future.

[crispyboy]

It could be one of many places a leak could occur.
- plastic flange that is between the tank and valve - had two cracked last year on our 1994 trailer
- valve body
- rubber Fernco fittings
- cracked ABS pipe


Here is a picture from an older 1989 trailer, our current 1994 trailer is ever so slightly different and your trailer is likely somewhat similar to our 1994 and should give you an idea of what to look for.
Cut an inspection hole and get a piece of flat galvanized HVAC duct work to cover the hole. Airstream dealer will have the parts.

[ROBERT CROSS]

Thanks guy's...just the info I needed. 👍
CB..the pic gives me a much better idea of where the inspection hatch needs to be. 😂

The leak at 5gal pointed me towards the valve but I wasn't sure of how the seals were installed on the slide.

Bob
🇺🇸

[ROBERT CROSS]

....it was the grey tank drain, opened it up today.

The flange was cracked on the tank side. OK, it may have had a defect. 🙄

But then I got it off and noticed the probable cause.
I believe the compression clamp was overtightened at install, warping the inlet and cracking the flange.

What thinks 'ye?

Thank You JC😟

Bob
🇺🇸

[GMFL]

I think you made the right choice to go to Cleveland.

[polarlyse]

Now that's a great photo of the valve arrangement & plumbing. I've been thinking about this job as something that we all much tackle eventually and my turn is coming any day now.

1. How much space is there between the cover and the tank.

2. . I'm thinking along the lines of how best to cut the access panel without putting a hole in the tank ???

3. Thinking ahead it looks as if we need to remove the 4 screws that sandwich the valve in place and slide the old out and new in. Is this an oversimplification and is it really that simple ???

4. What challenges are there to encounter in doing that ???

5. The nice top view is deceiving as seen. Working from below it looks to be difficult to access the screws on top of the valves. Do we need to cut the access to the front side also to gain better access ??

6. Do most replace with Thetford valves or Valterra and are they interchangeable.

Thanks all in advance.

[ROBERT CROSS]

It is difficult doing it upside down...the hex head screws on the worm drive clamps are doable 1/4 drive socket on a 4" extension. If your replacing the white slider valve, it must be cut out and a separate collar used to install it on the discharge side
The compression clamp on the tank side was under so much tension it almost took off my pinky when the Dremmel bit cut thru it...why the outlet was so deformed.

ODM is sending the parts...good thing is the slider is fine all I need to replace is the tank side flange, seal ring and new clamp.
Rust tells me it been leaking for a while. 😳

More photo's...
I should have widened the outer edge 1.5" would have been better. 👍
Bob
🇺🇸

[Wazbro]

First flush the tanks, then flush the tanks.



I used a 4 1/2" grinder with cutoff wheel to cut the pan.



Major thing to watch for is wires for sensors, on my 88 the wires were 8-10' longer then needed (after installed) and just laying loose in the pan.



Cut small hole, then bigger. Make the hole as big as possible while trying to leave enough past the edges of tanks to drill through (without hitting the tank) and rivet new piece on. You will wish for more room to work.


I went with Valterra valves on mine.