dump valve assembly

[Waipio Rim]

During our recent trip I got too cozy with a retaining wall in a gravel parking lot and snagged the combination black/gray dump outlet. The outlet connects to a 3" double ell, which connects to the dump valves, which connects to the tanks. The gray tank side of the assembly pulled out of the tank, and the downstream half of the black valve shattered at the connection with the ell. The gray tank was empty in a flash, but amazingly the remaining half of the black valve did not leak.

The tanks are now empty (please don't ask), but I gotta fix it first thing when we get back to the motorhome next spring. This stuff is all glued together and slip-fitted into the tanks, so I need to either replace the whole assembly or rig separate black and gray outlets.

I learned from a stop at a Camping World that pretty much none of the new stuff fits what I have, and they did not want to touch it. In desperation, I bought a couple of their dump valves and 4 flanges that I hope will adapt them to 3" abs. My plan is to take an ell, a piece of 3" abs, some glue, and a couple of slip fittings with me in the hope of creating a new dump valve assembly.

One problem that I see is that if I can actually create something that will fit, I won't have clearance to slip it in into the tank outlets. Do I need to remove a tank? What else will I need? Any advice will be appreciated.

[Silverflames]

Pics would help, do just some thoughts, they make glue that works on cpvc/abs/PVC. It can weld can different kinds of plastic together. Cut it back glue on an extension and put on a new v shut off valve. That should float you till you can pull down the belly pan fix it right. Down side is black water flows to your grey tank.

[bkahler]

Ouch.

Steve, I have the dump assemblies from the 345 sitting on the ground right now. When I get home next week I'll do a comparison of the 345 parts and our 310 to see what the differences might be. With luck some or most of the parts might work for you.

I'll post back here later next week with pictures and information.

Brad

[Waipio Rim]

Keith,
Thanks, the original assembly is more or less back in place with enough caulk in the gaps (there are some really big gaps) to have let me dump the tank without alerting the EPA. I may end up looking for better glue/caulk to get us down the road until we can really fix it.

Brad,
That would be great, thanks.

[Gypsy Jo]

vintage trailer supply was very helpful when I needed to do work on my dump valves.
Jo

[blickcd]

Here is a photo of my old dump valve assembly, which was leaking, so I removed it and replaced with new.

The black tank valve is the one on the left and is glued to the wye fitting. Dump valves on my trailer are Thetford, which are tougher to find, more expensive, but supposedly better quality than others.

You will see that the gray tank valve connects to a a stub of straight pipe off the wye and there is a slight gap which is bridged with a rubber coupling. That is the trick to giving you just enough slop to get the whole thing in place between the two tanks.

Maybe your two tanks and the fittings were glued together and dropped in place as a single unit on the assembly line. Now that you have to put it back together with the tanks in place, see if a rubber coupling will make it possible. No caulk should be needed.

Christopher

[Waipio Rim]

see if a rubber coupling will make it possible.

Christopher[/QUOTE]

Thanks, 3" rubber couplings are now on my shopping list. And yes, it's a cleanout tee, not an ell. I never was much of a speller.

[Chuckles]

I changed all my dump valves. Bought the Thetfords from Trailer Supply who also sold me the correct adaptor flange.

I replaced the dump valves on the black & grey tanks as part of the mascerator install. I fitted an extra 3" valve just before the hose coupling, so I can flush the black tank with grey water, without lifting the dump hose. Also if one valve does leak there is a back-up!

Caution, if you have it, the 'Y' piece is almost not available.... I tried all my trade suppliers without luck, so if you are changing the Thetford dump valves try not to damage the 'Y' piece. It probably would be cheaper and just as easy to use Valterra valves as the Thetford’s are a bit pricy.

I cut another 3" hole in the black tank inboard, just for the macerator. Using a Valterra remote cable controlled valve I can shut off the valve from by the rear wheel. With the pump fitted the other side of the prop shaft, it meant that the 3" flexible silicone hose had to have a section of S/S pipe fitted where it passes between the exhaust pipe and the chassis. As these pumps are self priming it is located, fixed to the underside of the floor. (Slight lift of about 8")

I do have some photo's somewhere and will look them out.

[Waipio Rim]

How has the macerator worked out? I have wished for a cleaner black water tank more than once.

I do still have the wye, or double ell, or whatever the correct name is. I have ordered a replacement and am awaiting delivery, keeping my fingers crossed that the overall dimensions are okay. The original is caulked to the motorhomes at the moment, and the problem that I foresee with reusing it is that there are the remnants of a broken flange glued securely to the black water side. Not sure I can cut those out and salvage it.

Did you have to move a tank to install the new assembly?

[Chuckles]

I didn't move any tanks. It took several hours to dis-assemble the old pipe and valves without breaking them but it was worth while. Just used loads of super glue or flexible body/ABS extended pipe sealant, when putting it all together again.

The macerator has been in constant use now for a couple of years and apart from one episode of someone putting a 'Wet-Wipe' down the toilet it has been faultless. NEVER ever use Wet-Wipes; ONLY toilet tissue, the macerator does not like them. It jams up with the eventual consequence of having to "get in there" and take the system apart complete with all the residues!

Not sure if I mentioned it but I use ordinary 1.1/4" convoluted hose for the dump side, bought a coil pack of 10Meters.. Using quick release couplings I have one length at approx. 15 foot ,another to join to it if I need an extension and the final one as a "just-in-case" I need more!

All the photos are on another PC and will retrieve them later.

Oh! and just a tip here... when dumping either with the 3" or macerator, as the tank empties I get 'er-indoors to fill the toilet boil to the brim with water and then open the toilet dump/flush valve. The force of a few gallons of water on to the floor of the tank does help to break up any solid that wish to stay! Two or three flushes like this and the tank remains reasonably clear.

[Waipio Rim]

Thanks, it's all back together now. The tee that I ordered online was an exact match, spent a cold morning at the campground/storage lot in Montreal in the spring of '13 fitting it with the valves and flanges from Camping World. Not sure how the abs is supposed to seal at the black tank. The hose clamp that was on there originally seemed to be pointless as the black tank flange is pretty rigid. Sealed a drip there with silicone, and it got us back to Montana in good shape. I pretty much gave up on the cleanout idea, just drag a hose inside and blast out the tank through the toilet as needed.

[Auretrvr]

I had to destroy the valves and clean glued fragments out the Ell when I repaired mine.

I did glue the new valves into the Ell. Need to make sure the glued assembly will end up allowing space for the entire setup to slide a few inches left or right to enable attaching the adapters to the valves while the adapters are dry fitted into the tank flanges.

I did not want to glue the assembly into the tanks, partly because the tanks are polyethylene and don't hold glue so well.

But what did work was to put two clamps on each connector, at 90 degree angles to one another, then tighten (almost enough to break the clamp), then rotate them both and retighten. Doing this routine was enough to obtain a good tight seal.

Now if the assembly has to be removed again it can slide left or right enough to remove an adapter at a time, instead of having to be sawed out.

Krylon Fusion has a metallic spray color that closely matches the gray Airstream paint on my 310; however my trim was repainted by P and S Trailer service (beautiful work) and is slightly different from the original gray, as I understand it.