Leaky Black Water Valve - what are my options?

[turbojimmy]

Here's a pic of the waste valve on my '84 Allegro:



I have a couple of problems. First, whatever style fitting that is won't accept newer hoses or caps. The only cap that will fit is the original, which has 2 tangs on it unlike new ones that have 4. I tried to use my brother's Rhino hose this past weekend (long story) and it wouldn't fit either.

The other problem is the black valve is leaking significantly. And the old cap isn't holding it back.

I'd like to replace that fitting with one that accepts newer hardware, but I don't know what sort of valve I'd have to get. The gray water valve is new (you can almost see it on the right). I don't have a lot of room to work with on the black water pipe. The valve is installed at the end of a 90-degree elbow. I'm afraid if I cut it off, I won't have enough pipe to install a new valve. Things would snowball out of control from there. I'm wondering if just that valve will come out and I can replace it with a new one? This wouldn't solve my fitting/cap problem but I have to stop that leak at a minimum.

[Matt_Colie]

Jimmy,

Dollars to donuts that is a Thetford valve. It should be held in place by 4 screws and be easily removed. Parts are available, but they are very proud of them. Don't order from Thetford unless you have a lot of time. They are real bad at shipping promptly - even when they already have your money. Just get to any good RV supplier and tell them you need the rebuild kit for a Thetford 3" valve. (Try Vintage Trailer) It will work unless that valve is old enough to be the stainless back side. I would doubt that. Unfortunately, all the newer valves use a different bolt spacing.

I do not believe that the T was a Thetford product. The mated flange is definitely not theirs. It is also not Valtera. That being the case, I don't think you have a lot of choice here. What I would do (fortunately, I don't have to), is get a Valtera or other common bayonet flange, then measure to see if it will fit on with the existing ears are removed. Then, carefully saw off the ears and glue the new flange over the old. This may require that you trim the OD of the remaining plastic. I don't know what tools you have available, so I hesitate to suggest a method.

Matt

[GlennLever]

Replacing the valve is not that hard.

When you replace it I would think you would be able to find the new style fitting.

I know this is not the same vehicle but maybe this helps?

Replaced both the gray and black water gate blade valves.

[John_Joey]

Can you take the old valve apart? What normally happens is some TP will get stuck in the groove and not allow the blade to fully close.

[dougrainer]

The Valve and the end cap is a "Thetford". Tiffin probably still have the Thetford valves and caps. Doug

http://www.amazon.com/s/?ie=UTF8&keywords=thetford+valve&tag=googhydr-20&index=aps&hvadid=2198668340...