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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Paul on July 13, 2009, 07:32:51 AM

Title: Waste Valves Flang Leak
Post by: Paul on July 13, 2009, 07:32:51 AM


This is a Valterra 3" valve
It leaks at the four bolt female threaded valve flange adapter to a 3" ABS plastic nipple from the tank.
The nipples bottoms in the fitting before it gets tight.

Do you think if I saw off some of the threads off the nipple this would help make it tighter so it wont leak?

Any help will be appreciated.
Paul
Title: Re: Waste Valves Flang Leak
Post by: jackhartjr on July 13, 2009, 07:44:26 AM
Hi Paul, coule you take a photo or two..that may help?
Thanks
Jack
Title: Re: Waste Valves Flang Leak
Post by: JackConrad on July 13, 2009, 07:46:44 AM
I would try a new O ring/gasket first.  Jack
Title: Re: Waste Valves Flang Leak
Post by: Paul on July 13, 2009, 08:05:55 AM


All parts are new. This is the first time that water was in the tank, we were doing a leak test and found the leak. It's a small leak but it's a leak! 
The leak is at the female threaded flange to the plastic nipple.  The nipple bottoms out in flange before it gets tight.

Paul
Title: Re: Waste Valves Flang Leak
Post by: Len Silva on July 13, 2009, 08:22:46 AM
Do you have the O ring installed?
Title: Re: Waste Valves Flang Leak
Post by: Len Silva on July 13, 2009, 09:01:22 AM
Sorry, I should have read your post more carefully.  You are talking about the threaded portion leaking, right?  I would say, just use a little more teflon tape on the joint.  For 3" pipe, I think 4-5 layers of tape would be appropriate.
Title: Re: Waste Valves Flang Leak
Post by: John316 on July 13, 2009, 09:28:36 AM
What about the liquid pipe dope? I love the blue stuff (vibration resistant) and use it on everything.

God bless,

John
Title: Re: Waste Valves Flang Leak
Post by: bobofthenorth on July 13, 2009, 10:31:15 AM
Its hard to say without a picture but based on my understanding of what you posted, yes, cutting the end off a tapered nipple should make it fit tighter.  I'd also use some good pipe dope on the threads.  I've never been a fan of teflon tape, particularly the home plumber variety.  If you insist on using tape then look for some of the 1" wide heavy tape.  Personally I prefer Tru-Blue (http://www.pipelinesupply.com/specsheet/Tru_Blu.pdf) pipe sealant.  I have used it on anhydrous ammonia, liquid fertilizer, propane and water lines and I never leave home without it. 
Title: Re: Waste Valves Flang Leak
Post by: gumpy on July 13, 2009, 11:09:23 AM
Yeah, mine did that when I installed them. The bottoming out causes the flange to warp.

You need to take the flange off the nipple, and coat the threads liberally with white Teflon pipe dope. Then, when  you put it back together, don't tighten it till it bottoms out. The dope will seal the threads and the flange will not warp.

craig
Title: Re: Waste Valves Flang Leak
Post by: kyle4501 on July 13, 2009, 01:31:29 PM
I've never had a leak when using the Tru-Blue dope.  8)
I can't say the same for the teflon (tape or dope). But, maybe I didn't do it right . . .  :(
(don't you just hate crappy leaks?  ;) )

I'd use the best pipe dope I could get & do not over tighten it, let the dope do it's thing.  

Good luck  ;D
Title: Re: Waste Valves Flang Leak
Post by: John316 on July 13, 2009, 02:00:27 PM
Thanks Bob. I meant that Tru-Blu teflon stuff. It is great. I have used it on water, air, fuel, and any other fittings that I can get it on ;D.

God bless,

John
Title: Re: Waste Valves Flang Leak
Post by: bobofthenorth on July 13, 2009, 02:07:59 PM
We used to have some really nasty black stuff that we used on NH3 but my preference is to use Tru-Blu for every threaded fitting.  The nice thing about Tru-Blu is that it crusts over so it doesn't get on everything for the rest of its life but it stays flexible inside the joint.  The black stuff on the other hand was just plain nasty forever.
Title: Re: Waste Valves Flang Leak
Post by: Melbo on July 13, 2009, 06:00:33 PM
Not that what has been posted won't work but I used teflon pipe dope and then put a hose clamp on one fitting that had a slow drip in my fresh water system.

I checked with the people who built my tanks (actually I was complaining about my leak) and they said I could screw the plug (1 1/2 inch for a quick drain) all the way into the tank and the threaded flange would just spread open till the plug went into the tank.

They said the plastic (HDPE) will just keep stretching. So I backed the plug out a bit (the tank was full and I did not want to drain it) put a heavy duty hose clamp around the flange tightened it as much as possible and then retightened the plug and the leak was stopped.

HTH YMMV

Melbo
Title: Re: Waste Valves Flang Leak
Post by: John316 on July 13, 2009, 06:33:17 PM
Melbo,

I had to laugh. It sounds like that is a good idea to make is stop leaking, but I also read your tagline. It sounds like that kind of fix is right down your road ;D.

God bless,

John