Author Topic: Tank Smell Inside  (Read 1830 times)

Dennis Belfils

  • BAC Member
  • *
  • Posts: 38
  • Thanked: 5 times
Tank Smell Inside
« on: November 04, 2018, 08:29:50 PM »
I have tried searching the forum for a similar issue with no success. We have a very strong smell from the bath/sink areas that appears to be gray tank. It only occurs in the morning while running water in the sinks/s. It is very potent & seems like gray tank stink. It only occurs when not hooked up to sewer & becomes stronger as the days progress before dumping. We have upgraded the vents under the sinks & have even plugged them with pipe plugs. There is only one vent on the roof & I can only assume that both gray & black are common vents. There are 3 pipes entering the gray, which may be, the toilet/bath sink, shower & shower area sink & vent to roof. Black has entry pipe & vent next to it. The only other change was Sealand toilet to a Dometic with the proper adaptor plate. Any out of the box ideas would be appreciated
2006 Monterey Montclair IV
Cat C-9 400HP

Joel Ashley

  • BAC Member
  • *
  • Posts: 1748
  • Thanked: 593 times
  • OSU Class of '73, Oregon Native. RVing 35 years
Re: Tank Smell Inside
« Reply #1 on: November 04, 2018, 08:55:09 PM »
Sounds like you’ve already covered this, but the only time we’ve had the issue was when our shower trap went dry.  Pouring a cup or two of water down the shower drain always alleviated it.

Do you have a washer/dryer that hasn’t been used for awhile?

Joel
Joel and Lee Rae Ashley
Clackamas, Oregon
36.9 ft. 2006 Monterey Ventura IV, aka"Monty Rae"
C9 400HP Cat
towing a 1997 Ford Explorer Limited, aka "Pearl"

Fred Cook

  • BAC Member
  • *
  • Posts: 350
  • Thanked: 56 times
Re: Tank Smell Inside
« Reply #2 on: November 04, 2018, 09:37:05 PM »
I had the same problem. I replaced all the P-trap vents, at least I thought I did. There is also a vent for the shower P-trap that I had a really difficult time to get to. I actually had to take down the bedroom wall to access it. I replaced it and that solved the problem. I also cut a hole in the wall and covered it with a vent for easy access in the future.  I also replaced the P-trap for the washer and strung an ice-maker hose to it so that I would be able to pour water into the trap in the future without taking out the washer.  But if you use your washer after enough you wouldn’t have to do that.
Fred & Cindy
2002 Beaver Patriot Thunder 455, C12 CAT
Towing 2019 Chevy Equinox, AWD Diesel
South Central Missouri, US Army Retired

Steve Huber Co-Admin

  • Administrator Group
  • *
  • Posts: 2581
  • Thanked: 1756 times
Re: Tank Smell Inside
« Reply #3 on: November 04, 2018, 11:28:01 PM »
Steve
2015-          07 Contessa Bayshore C9,  400 hp
2013-2015: 00 Marquis Tourmaline, C12, 425 hp
2005-2013: 01 Contessa Naples, 3126B, 330 hp

Bill Sprague

  • BAC Member
  • *
  • Posts: 803
  • Thanked: 418 times
Re: Tank Smell Inside
« Reply #4 on: November 05, 2018, 04:50:08 AM »
Dennis,

Your signature shows you have an '06 Monterey.  We had an '04 for a dozen years.  And, we would too frequently get the stink.  I did all the obvious stuff with the traps and check valves for the three sinks and shower. 

It finally turned out to be the drain for the Splendide.   It seemed to be two related problems.  The hose from the Splendide was long enough that it somehow drained, blew out or siphoned the trap.  Or, the trap may have dried out or sloshed out on it's own. 

Changing how much Splendide hose was in the drain line fixed the stink.
Bill Sprague
Past Region 1 VP
2019 Tiffin Wayfarer 24TW
Past 3 year owner '15 PleasureWay Pursuit
Past 12 year owner of '04 Monterey w/Cummins ISC 350

Dennis Belfils

  • BAC Member
  • *
  • Posts: 38
  • Thanked: 5 times
Re: Tank Smell Inside
« Reply #5 on: November 05, 2018, 03:27:59 PM »
Thanx Bill. How much hose from the Splendide did you put down the drain?
2006 Monterey Montclair IV
Cat C-9 400HP

Bill Sprague

  • BAC Member
  • *
  • Posts: 803
  • Thanked: 418 times
Re: Tank Smell Inside
« Reply #6 on: November 05, 2018, 05:10:19 PM »
Dennis,

I'm going from memory.  I "fixed" it several years ago.  What I remember is that I ended up with about 6" of Splendide hose down the drain line.  My reference was how a stick house washer works.  The only important part is that it drains and doesn't fall out when you go over a pothole!
Bill Sprague
Past Region 1 VP
2019 Tiffin Wayfarer 24TW
Past 3 year owner '15 PleasureWay Pursuit
Past 12 year owner of '04 Monterey w/Cummins ISC 350

David T. Richelderfer

  • David, Leslie & Jasper
  • BAC Member
  • *
  • Posts: 1253
  • Thanked: 354 times
  • 2004 Marquis Sapphire 45, C12 - 505 hp
Re: Tank Smell Inside
« Reply #7 on: November 05, 2018, 05:58:22 PM »
A few weeks ago while on our trip south to Yuma we had a tank smell when the fantastic fans were open with fans on while parked at the Whiskey Flats RV Park in Hawthorne, NV.  I was trying to cool the bedroom for the night so had only two bedroom windows partially open.  The problem was the suction provided by the fans was pulling a little tank smell up through the Splendide drain.  I put the Splendide on a rinse cycle for a minute or two to get water into the drum, then switched it to a spin cycle to evacuate the water to the drain.  Problem solved...
David, Leslie & Jasper
Towing a 2002 black Chevy Avalanche
Using a Blackhawk Towbar & Evenbrake
RF Mogul Eagle 3 for DISH TV
Go Beavers, OSU Class of '71, Math
RVing since 1973
Constitutionalists, Golfers & Capitalists
Your luck is the residue of your management

Steve Huber Co-Admin

  • Administrator Group
  • *
  • Posts: 2581
  • Thanked: 1756 times
Re: Tank Smell Inside
« Reply #8 on: November 05, 2018, 08:21:51 PM »
Dave,
To cool the bedroom faster, open the engine cover when parked for the first hour or so. Really helps.
Steve
Steve
2015-          07 Contessa Bayshore C9,  400 hp
2013-2015: 00 Marquis Tourmaline, C12, 425 hp
2005-2013: 01 Contessa Naples, 3126B, 330 hp

Dennis Belfils

  • BAC Member
  • *
  • Posts: 38
  • Thanked: 5 times
Re: Tank Smell Inside
« Reply #9 on: November 06, 2018, 03:47:27 PM »
Thanx to all for input. Have corrected drain from W/D & am using the suggested tank treatment.
 Is it a common practice to combine the gray & black vents for only one roof penetration? We would like to install the Cyclone cap, but are concerned about it pulling the traps dry while driving.
2006 Monterey Montclair IV
Cat C-9 400HP

Joel Ashley

  • BAC Member
  • *
  • Posts: 1748
  • Thanked: 593 times
  • OSU Class of '73, Oregon Native. RVing 35 years
Re: Tank Smell Inside
« Reply #10 on: November 07, 2018, 10:08:07 AM »
The anti-vacuum devices (in-line vent similar to this one:   https://www.hardwareandtools.com/oatey-39012-inline-vent-ecja-8601.html ) above each trap should prevent P-trap emptying, but not if road movements empty them or a device has failed.  I suspect that’s what’s wrong with my shower drain issue... a stuck-closed inline vent valve that allows the infrequently used shower trap to vacuum dry each time I empty the gray tank.  If there isn’t enough water weight in the trap to be more than the inline vent’s spring strength, the spring may keep the vent sealed, and the rest of the trap water gets sucked out.  I don’t know that it’s too hard to check and remedy the spring/seal movement.

Not sure how you “upgraded” the under sink vents or why you’d have additionally “plugged” them, unless it was an Oatey Surevent, a Hepvo, or something like this    https://www.ipscorp.com/pdf/studor/STU021_TrapVent_web.pdf  .  It may have been unnecessary if the Splendide was the culprit all along.

You’d think a roof vent would prevent siphoning, but a one-way valve there may mitigate air coming in via the roof vent.  And as to your combined vent question, I’ve heard of that;  but the ‘06 Monty’s I’ve seen all had two side-by-side “T” roof vents, as does mine - so reckon I can’t offer much insight there. 

Also it’s advisable to not leave the dump valves open to the park sewer while camped.  Accumulated tank fluids flush solids best all at once.

Joel
Joel and Lee Rae Ashley
Clackamas, Oregon
36.9 ft. 2006 Monterey Ventura IV, aka"Monty Rae"
C9 400HP Cat
towing a 1997 Ford Explorer Limited, aka "Pearl"

Dennis Belfils

  • BAC Member
  • *
  • Posts: 38
  • Thanked: 5 times
Re: Tank Smell Inside
« Reply #11 on: November 08, 2018, 03:03:45 PM »
The upgrade was to Studor Redi-Vents. In an effort to locate the source of the smell, the Studors were temporarily replaced with plugs. And yes, there is only one T on the roof, directly above the Toilet Lavy. The park we are in  does not have sewer hook-ups, but do provide tank pump-out. The smell is quite strong a day or so before pump-out. Locating the source is the problem. It shows up when running water in the sink of either Lavy.
2006 Monterey Montclair IV
Cat C-9 400HP

Steve Huber Co-Admin

  • Administrator Group
  • *
  • Posts: 2581
  • Thanked: 1756 times
Re: Tank Smell Inside
« Reply #12 on: November 08, 2018, 03:32:51 PM »
Dennis,
We also fought a grey tank oder in our 01 and 00 coaches. In both cases I found the source of the problem was the vent under the bathroom sink. Replacing it didn't completely solve the issue so I used a formaldihyde based tank treatment in the greay tank to cover the odor, added a lot of water to the tank as most odors are due to lack of water in the tank. When we got home, I drained the tank, filled it with fresh water and added about 2x the recommended dose of Tank Tech and let it sit of a few days. Then drained the tank (not completely though) and started using it again with no more issues. Important to alway leave some fluid in the tanks when draining and to add water after draining (I add about 3 gallons to each tank).
Steve
Steve
2015-          07 Contessa Bayshore C9,  400 hp
2013-2015: 00 Marquis Tourmaline, C12, 425 hp
2005-2013: 01 Contessa Naples, 3126B, 330 hp

Bill Sprague

  • BAC Member
  • *
  • Posts: 803
  • Thanked: 418 times
Re: Tank Smell Inside
« Reply #13 on: November 08, 2018, 03:48:01 PM »
Around the 8th year of owning our '04 Monterey it was time to rebuild the toilet valve.   Although bleach comes in plastic bottles, the common advice is that it can harm the plastic in RV systems.   I decided to take a risk!

I filled and drained the black tank twice.  Then I poured in a full gallon of bleach and filled it again.  I (patiently) waited five or ten minutes and drained the tank. 

I removed the toilet and went to work on rebuilding it.  With the hole into the black tank wide open, there was no smell at all.  The bleach killed whatever may have stunk. 

There was no apparent change or damage done to the RV's plastic parts.   The tank drain valves functioned normally for the next few years.  If the five or ten minutes of exposure to bleach did any damage, it was undetectable. 

Bill Sprague
Past Region 1 VP
2019 Tiffin Wayfarer 24TW
Past 3 year owner '15 PleasureWay Pursuit
Past 12 year owner of '04 Monterey w/Cummins ISC 350

Greg Kamper

  • BAC Member
  • *
  • Posts: 71
  • Thanked: 15 times
Re: Tank Smell Inside
« Reply #14 on: December 05, 2019, 05:26:48 PM »
I know this is an old post... but I too poured about a cup of water in the washer/dryer before our last trip home and ran the spin cycle. We had zero odor on that trip home. That was a first for us in the 5 years we've had the coach. :D
Greg & Angel and kids...
2000 Beaver Patriot Thunder Monticello