[pestes]

Kelly noticed a small puddle under the coach after coming back from a hike this morning.

Tracked it to the Dupree curb side dump valve. I can see a slow'ish drip coming from the bottom of the valve body. Of course, it's holding tank, so even a slow drip is not slow enough.

I found some old threads on replacing the gate and seal assembly. But I am concerned -- could that deformed seal cause a leak out the body? I'm thinking that the valve body must be cracked or something. I just dug up these threads and it's dark now, so I have not had a chance to take the valve apart to look closer. I am very much hoping that I do not have to replace the body - there's maybe 1/2" between the valve and the holding tank.

And of course it had to be the curb side dump. At least on the proper dump valve I could just use the gray water bypass to keep from leaking.

[encantotom]

i would be surprised if the valve body is cracked. possible, but not likely. i would more suspect the seal is just bad. i would rebuild it and see if it fixes it. you just need a new rubber paddle.

start with that. sometimes they are very fun to get out.

my two cents worth

tom

[folivier]

And if it cracked and you don't plan on ever using that dump you could always get a plug that fits the hole. My '93 (Jon's coach) has a plug rather than the dump valve on the curbside.

[pestes]

Thanks Forest. Capping it off was actually my first thought. Luckily I'm just barely smart enough to check Newellgurus first to find out that there is hope!

Newell is overnighting me their last gate & seal assembly. Somehow they were a few bucks cheaper than Dupree's price on it.

[pestes]

Received the new gate from Newell. There's also a loose O-Ring in the bag. Before I tear this apart tomorrow, I was wondering if anyone could tell me how the O-Ring fits into the equation, I was not expecting it.

[folivier]

Is it a small o-ring? If so it fits on the handle shaft.
If it's a large o-ring I think that fits into a groove to seal the top piece from the chamber, which is rectangular.
Here is the parts breakdown from Dupre's webpage: http://www.dupreeproducts.com/SearchResults.asp?Cat=12

[pestes]

Thanks Forest! Somehow I had missed that breakdown even though now I see it right on the menu right there in front of me. Doh!

[cknuth]

Howdy, I'm once again firing up an old thread as the discussion seems relevant.    I typically run my waste as others do: grey water bypass and occasional dumping of the black water.  So the front valve is open and the rear valve closed.    My rear "bypass" valve is air operated with a manually accessible handle.  It has gotten so sticky that the air won't open it and manual force is needed.  I'm pretty sure it's not low air pressure as it closes easily with the air control.    Lithium grease on the exposed shaft has had no effect.    Is there some way to open up this valve for rebuild/lubrication?  Seems very much glued in and inaccessible.

   

[Richard]

Absolutely. Look at the top of the valve body where the air operated shaft enters. You will find two screws. Remove them, and the top, along with the shaft and the "paddle" will come out. It can take some force. You can simply order the rubber insert for the paddle from Dupree. They get old and cranky, and begin to stick. Chlorine (bleach) in the water does that to rubber. I carry spares, of this item. Seems mine requires replacement about every five years.

Pay attention to the orientation of the paddle when it comes out. The insert wedge is asymmetric, and must be reinstalled in the body the way it came out. You will know if you got it backwards because the valve will not shut completely. No worries, pull the top off and rotate the shaft 180 degress. Lube the insert with silicone when reinstalling.

[encantotom]

when the tank is totally empty, i would take the screws out of the top and take the entire interior assembly out.

if it is sticking it is one of two things. the first being the unit itself. it can be easily rebuilt and i have done several. you can try the thing when it is not installed (except for air) and see if it moves freely. the paddle that is on the unit often gets distorted and wont go into the slot that is on the bottom of the body of the fitting that is glued in.

if it is old, i would probably replace it if it looks distorted at all.

the second is if there is debris in the bottom of that valve body in the slot, making it hard for the paddle to go down in there.

i use a boroscope to see down in there or take a picture with your phone. then you can take a long flat screwdriver and gently clean that slot out.

parts have been avail in the past and i always keeps spare paddle, paddle assembly and cylinder rebuild kit.

tom