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Black waste tank vent

Journey, Roam, Explore Bob is here and is resolving some maintenance issues. He came across the waste tank vent install nearly resting against the angled part of the tank probably 3-4 inches below the top of the tank. The tanks has been removed prior and I suspect that they reinstalled with excessive penetration. Does anyone know how much they the should extend into the tank. The only reason he noticed was he was replacing a tank cleaning system nozzle and could view the vent pipe inside the tank. I don't see any reason to need a 3-4 inch expansion area.
Scott

Re: Black waist tank vent

Reply #1
Journey, Roam, Explore Bob is here and is resolving some maintenance issues. He came across the waste tank vent install nearly resting against the angled part of the tank probably 3-4 inches below the top of the tank. The tanks has been removed prior and I suspect that they reinstalled with excessive penetration. Does anyone know how much they the should extend into the tank. The only reason he noticed was he was replacing a tank cleaning system nozzle and could view the vent pipe inside the tank. I dont see any reason to need a 3-4 inch expansion area.
Scott
Scott..They may all be like that. I dont know !! I see no purpose of it.
Hans & Marjet
1995 U300 "Ben" (#4719)
3176B Cat,4060HD,Jake
SKP#139131
Motorcade#17579
2006 Honda Element (towed)

Re: Black waist tank vent

Reply #2
I know on my coach the vent pipe is on the squared end and the toilet drop in on the sloped side with about a 1/2 inch below the top of the tank. No clue what my vent is? I dont even know if its good practice to even have a expansion area?

Re: Black waist tank vent

Reply #3
If they protrude inside, it may reduce sloshing and forcing water up the tube. ??

Re: Black waist tank vent

Reply #4
Downside would be no air removal if above the bottom of the tube. Would have to do a one for one air exchange when using the toilet. That's not good at all

Re: Black waste tank vent

Reply #5
True , it will air lock just above the tube.

Re: Black waste tank vent

Reply #6
Scott,

On our tank the vent sticks down no more than 3/8" below the gourmet that holds/seals it in the tank.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Black waste tank vent

Reply #7
Scott,

On our tank the vent sticks down no more than 3/8" below the gourmet that holds/seals it in the tank.

Mike
Thanks Mike. I think I will use a hole saw threw the cleaning opening and open up a higher vent point. To remove the vent and do properly would be real difficult. I'm confident I'll be able to retain the cut out holes using a long pilot drill. I also think they would also pass if they were dropped. Kinda feel like it's knocking at the door of Pandora's box. Dont want to do more damage than what we already have. Opening up a vent hole should help, IMO.

Re: Black waste tank vent

Reply #8
Yeah over the years I've had some issues draining the black tank. It seemed like when I would open it up it would hesitate and then drain for a little before I could hear a rush of air and then the tank would drain completely. The black tank rinse that a previous owner put in I was basically doing nothing and now I know why.
I'm pretty sure this is when that company in nacogdoches replace the basement for a previous owner. All the tanks were removed. They just didn't do a very good job of reinstalling them or other things too. Scott drilled through the pipe and now it should vent better. The tornado black tank rinse that I purchased 2 years ago and has been sitting in a box in one of my bays, never came with the actual tank flush only the hose to it so I'm waiting on a new one from Amazon.
We'll have to seal up the old hole and cut a new hole for the rinse away from that pipe. There's not a lot of room but there's enough.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Black waste tank vent

Reply #9
Did you get a stink when you flushed the toilet? When I flush the toilet I get a stink and I have
put on a new vacuum breaker and a different vent cover and I'm still trying to figure what the
cause is. 
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Black waste tank vent

Reply #10
Peter, are you flushing the black with gray like some are doing? We found the gray causes the black to smell when flushing toilet.

We did add a fan to the black ABS vent pipe on the roof, but did not need to use it very much after adding roof venturi.

May get a smell while driving if air flow puts pressure into tank.

Re: Black waste tank vent

Reply #11
That's good to know and I don't get any stink from driving just flushing.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Black waste tank vent

Reply #12
Did you get a stink when you flushed the toilet? When I flush the toilet I get a stink and I have
put on a new vacuum breaker and a different vent cover and I'm still trying to figure what the
cause is. 
Yes especially if the fan is on.
I do back flush my black tank with the gray.
I like to flush my black tank too but noticed that it really wasn't doing very much and now I know why. It was blocked. Got the new black tank flush in the mail yesterday will install it today and see.
On my 40 foot center cockpit endeavor sailboat when I redid the waste management system I put in two vents into the black tank so that they will always be a flow of air in and out. Kind of wish foretravel had done the same thing, but it is what it is. I do put some microbes in my tank once in a while to digest things if it would be a while before I dump again, and every once in awhile I put borax as well as dishwashing liquid into the black tank and let it slosh around for a while before emptying it and that tends to clean the tank too. I know that it does because my sealevel tank monitoring system works better after I do it.
I always love it when it says my tank's at 47% when I know I just emptied it. That's how I knew I had a problem with my black tank flush.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Black waste tank vent

Reply #13
Did you get a stink when you flushed the toilet? 

Flushing with the fan on will do that unless you have some windows open.  The air has to come from somewhere.
Dave and Kelli
1997 U295 40' Build #5188 CSGI
1995 U240 36' Build #4621 SBID-SOLD
2006 Jeep Wrangler Rubicon

Re: Black waste tank vent

Reply #14
Thanks Bob I will take my flush valve off soon and see if my vent is too long. My flush valve
is hard to get at and I don't think I can get a hose on it because who ever ran the hot water
pipes twisted them around each other so I can't get to the valve.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Black waste tank vent

Reply #15
Flushing with the fan on will do that unless you have some windows open.  The air has to come from somewhere.

Actually, VERY few will ever flush a second time with the vent fan on!  LESSON LEARNED and imprinted!
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Black waste tank vent

Reply #16
Brett, thanks for the laugh.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Black waste tank vent

Reply #17
Thanks Bob I will take my flush valve off soon and see if my vent is too long. My flush valve
is hard to get at and I don't think I can get a hose on it because who ever ran the hot water
pipes twisted them around each other so I can't get to the valve.
Unless it's broken and you really need it don't mess with it you might just open up a really dirty can of worms.
Believe it or not I really did fix it today but didn't take any pictures it's still a work in progress.
I took the old piece of junk out and put the new piece of junk in made by camco. It doesn't look high quality.
Of course I had to drill a new hole it called for one and three quarter inch hole, I only had a one and a half inch hole saw, I figured what the heck I can always use a file, but no the one and a half inch did just fine.
Dsd's water pressure here is a little high, so I think it took a micrometer off the inside of my black tank but seems to be working fine. Use some of his fancy aircraft adhesive silicone. Mine is clear in his is red. Like a brick red.
He has a lot of stuff like that. Not to mention a really Kick-Ass Ford bronco that he's totally modified. Well maybe not totally but quite a bit.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

 

Re: Black waste tank vent

Reply #18
Actually, VERY few will ever flush a second time with the vent fan on!  LESSON LEARNED and imprinted!
Yeah Brett, remember I was a nurse for 35 years and the smell of poo doesn't really bother me too much.
And that is probably TMI....
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired