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Topic: Problems with third dump valve mod (Read 2890 times) previous topic - next topic

Problems with third dump valve mod

I started the third valve mod today but am stumped on a problem getting the flanged fitting, e.g. the first piece to go on, over the dump pipe. The flange sticks down too far as there is only about 3/16 clearance under the 3 inch pipe. Did anyone else have this problem? How did you solve it?

Re: Problems with third dump valve mod

Reply #1 –
I had the same problem. I just pried the pipe up with a pry bar and glued on the new valve. Once glued on I removed the pry bar and the pipe leveled out and works fine.

Re: Problems with third dump valve mod

Reply #2 –

  I had a similar problem when adding the third valve. I used wooden wedges under the black ABS pipe behind the compartment
  panel to give required clearance.  After cement sets up---remove wedges---all good.

Re: Problems with third dump valve mod

Reply #3 –
I would like to do this on my 91 what do I need to get?

Re: Problems with third dump valve mod

Reply #4 –
Quote from: stump –
...what do I need to get?
Open up the bay enclosure so your waste dump pipes are exposed.  Decide what kind of 3rd valve setup you want (search subject on Forum for ideas).  Cut off old valve flange.  Install new flange and valve.  While you're at it, if your original dump valves are old, you should take the opportunity to replace them also.  Here's what our plumbing looked like, and the parts I used (3 of the Bladex valve bodies, plus 2 flanges, and cap):

Amazon.com: Valterra T1003VPM Bladex 3" Waste Valve Body with Metal Handle:

Amazon.com: Valterra T1005 3" Slip Hub Flange: Automotive

Amazon.com: Valterra T1009 3" Bayonet Flange: Automotive

Amazon.com: Valterra Products, Inc. T1020 3" Black Termination Cap with Bayonet
As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: Problems with third dump valve mod

Reply #5 –
I also did as the others and very gently adjusted the fixed pipe upward, cut and glued on the new end piece.

I did not glue on a third valve, but bought the clip-on-removable third dump valve and use it when or if I want.  It kept the compartment simpler and gives me some more room when we are hooked up full time, not just a dump and run.  I do like having the third valve for back flushing the black tank, and can see thru the clear pipe when the black tank is flowing clean.

Re: Problems with third dump valve mod

Reply #6 –
Hi Royce,
  Our 1997 U 320 had a small piece of wood about 5/8" thick under that piece. I put another piece under the black tank tube just before the dump valve to have more even support.
Raymond