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Topic: Another Stinky Coach (Read 1197 times) previous topic - next topic

Another Stinky Coach

We suffered the dreaded stink syndrome day before yesterday. This coach (95 300) has four air admittance valves: under sink; behind toilet; and two in the closet. One of these is for the shower presumably and the other for the washer. I removed the washer when we got this one and sealed the washer pipe. Anyhow, the stench emanates from the closet and worsens when we have  negative pressure in the coach. Goes away with positive pressure. I replaced both with Home Depot or Lowes units and that fixed it - FOR ONE DAY. Now it's back.

When we had our 320 I had the same problem. i.e. replaced the valves with Home Depot cheapies. They worked but only temporarily. To permanently resolve the problem in the 320 I bought (per Michelle's recommendation, I think) Studor 20349 ABS valves. They are pricey but the smell never returned. We are full timing now (kinda, sorta, I guess) so I'm not screwing around with this. I'm ordering four of the hot shot Studors.

So what, you say? Well, I'm thinking about replacing the top of the roof vent with one of those Cyclone deals and I'm wondering if anyone has done so and/or had a recommendation of what to buy. Thanks.
jor
93 225
95 300
97 270
99 320

Re: Another Stinky Coach

Reply #1 –
Use Oxy-Kem holding tank treatment, dump black once a week, let grey flow through to sewer, although grey will stink up once and a while in hot weather.

Re: Another Stinky Coach

Reply #2 –
My "T" shaped roof top vent had some branch damage so I replaced it with one of those turn in the wind Cyclone vent caps.  It will get a three month test in two weeks.  I have new inside vent tops too but have not put them on.  Hoping this will keep the odors going the right direction.  Not a problem too often.  Driver's side window seems to suck air out of the coach, passenger's side seems to push air in.  Better to have positive interior pressure.  Roger

Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Another Stinky Coach

Reply #3 –
We still have the original "T" shaped venturi vent on our roof.  Last trip out, I hooked it on a low branch and broke a large piece off.  I ordered the Camco Cyclone from CW (on sale now) and it just arrived today.  Will get it installed this weekend.  Looks like it ought to work - it swivels very easily, almost like on a bearing.  Plastic, of course, but not cheap or flimsy feeling.  It won't stand up to tree branches any better than the old one, but I figure it's worth a try.

Cyclone Sewer Vent - Camco 40595 - Sewer Accessories - Camping World

I've also read some good reports on the "Lil' Stanker".  Might be a good "Plan B" if the Cyclone isn't sufficient or doesn't hold up.

Lil' Stanker™ In-Line Deodorizer Fans
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Another Stinky Coach

Reply #4 –
Hey Jor that is a real stinking deal lol, We had the cyclone on the Eagle and it worked really well I plan on putting one on this old girl. It turns with the wind  8)
Andy & Eileen
MONTROSE COLORADO
1992 U300  40' 6V92 TA
2016 4 Runner
1998 Jeep Grand cherokee

1998 Jeep Grand Cherokee) Build # 4135 Skp# 122921

Re: Another Stinky Coach

Reply #6 –
Thanks to all. I'm going to pick up one of those 360 deals. I have a question, however, regarding the Studor air admittance valves. I ordered four from Amazon but they aren't able to deliver until late July. We surely won't still be here then (Angel Fire).

I haven't been able to find this model elsewhere. There are, however, places that sell the Studor 20346 which is meant for PVC. Are the threads on PVC different than ABS? Is there any other reason I couldn't use the PVC one in lieu of the ABS? Thanks.
jor

UPDATE: Answered my own post. One of the eBay sellers wrote to advise me that the only difference between the PVC and ABS models is the ABS requires a different cement or a universal.
jor
93 225
95 300
97 270
99 320

Re: Another Stinky Coach

Reply #7 –
Actually John after going thru this problem a few years ago I believe it all has to do with the positive/negative thing.
I installed the cheap ones, and put the cyclone whirlybirds on the roof stacks and still had a bit of the problem. Now I turn on the fan to create a positive pressure and never a smell. Your findings may differ though.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Another Stinky Coach

Reply #8 –
Quote from: John Haygarth –
Now I turn on the fan to create a positive pressure and never a smell.

I'm not clear on what fan you turn on to "create a positive pressure".  The roof fans (at least in our coach) lower the pressure and tend to draw fumes from the black tank into the coach.  The only fan I am aware of that would "pressurize" the interior is the dash A/C fan set on "fresh air".  Care to elaborate?
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Another Stinky Coach

Reply #9 –
I too would love to hear this one as I need to know what fan you are using.  Tks
Dan & Shirley Stansel
2002 U295 4020 AGDS Build#6054
Towing Buick Enclave & M &  G Braking
Emerald Bay, Lake Palestine, Texas
MC# 16650

Re: Another Stinky Coach

Reply #10 –
Quote
Now I turn on the fan to create a positive pressure and never a smell.
That's what we are doing now while we await deliverance from Studor. Instead of turning on the Kool-O-Matic or the bathroom fans, I either have a couple of windows cracked (no smell) or one of the A/Cs on fan only (also no smell). The only time we get smell is when there is negative pressure in the coach. The smell emanates from the closet where there are two air admittance valves.

My opinion is you cannot stop either tank from smelling; they are holding tanks after all. They are designed with a vent stack so the odor should never be present within the coach. If the stack is unobstructed and the air admittance valves are working properly, there should not be any odor in the coach under normal circumstances. You can clean the tanks so they are nice and shiny but as soon as you flush the toilet  or take a shower they are once again holding tanks and that stuff smells.
jor
93 225
95 300
97 270
99 320

Re: Another Stinky Coach

Reply #11 –
Quote from: Chuck & Jeannie –
I'm not clear on what fan you turn on to "create a positive pressure".  The roof fans (at least in our coach) lower the pressure and tend to draw fumes from the black tank into the coach.  The only fan I am aware of that would "pressurize" the interior is the dash A/C fan set on "fresh air".  Care to elaborate?
Many "Fantastic" fans have a reversible option to pull air in at the fan (pressurizing the rig) as opposed to pulling it out (suction in the rig) .
Rick

Re: Another Stinky Coach

Reply #12 –
Reversible fans - that would be a nice option - ours do not have it.  I would, however, question the cost/benefit ratio of such a procedure.  After spending the time and energy to get our coach comfortably warm (Winter) or cool (Summer), do I really want to suck a large volume of outside air into the coach, just to avoid "stinky coach" syndrome?  I think not.  I would rather address the problem by generating sufficient vacuum in the holding tank, either passively ("venturi" roof vent) or actively (powered exhaust fan on vent pipe).  Just seems more efficient to me...

By the way, this brings up a question: are both holding tanks vented through the roof vent, or only the black tank?  The grey tank also gets smelly.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Another Stinky Coach

Reply #13 –
sorry, yes the dash fan!!
By the way, not sure if anyone knows how the valves are made but inside is a VERY flimsy/Flexible rubber diapraghm that even a slight vacuum will dislodge it. I have in the past taken off this piece and reversed it and it actually holds better due to the derformed shape it has got over the years. I have not bought the better ones as I do not have any more smells emitting from pipes.
Yes, both should be vented just like your home plumbing, and it also helps with the draining of water out of the sinks as air is sucked back down the pipe so a vacuum is not created when draining the sinks. Air should be able to flow TO the tanks but not BACK from the tanks.

JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Another Stinky Coach

Reply #14 –
Quote from: Chuck & Jeannie –
.....do I really want to suck a large volume of outside air into the coach, just to avoid "stinky coach" syndrome? .....
That's up to you.
You asked.
Quote from: Chuck & Jeannie –
I'm not clear on what fan you turn on to "create a positive pressure".  The roof fans (at least in our coach) lower the pressure and tend to draw fumes from the black tank into the coach.  The only fan I am aware of that would "pressurize" the interior is the dash A/C fan set on "fresh air".  Care to elaborate?

I elaborated.

There are other benefits to pulling air in from the top as well.

Rick

Re: Another Stinky Coach UPDATE

Reply #15 –
When I started this thread I had just installed new air admittance valves in order to cure a stinky coach. They were from Home Depot. They worked for a day and then failed. I am happy to report that the pricey Studor valves cured the problem permanently as they did on another coach of mine. Anyhow, before taking any heroic measures after failing with the big box store product, try a Studor.
jor

93 225
95 300
97 270
99 320

Re: Another Stinky Coach

Reply #16 –
Forgot that I took a photo of the new Studor vents. These two vents serve the washer and the shower. I took the washer out of this coach. They might be hard to get at with it in place. The round hole is the vent for the dryer through the side of the coach.
jor
93 225
95 300
97 270
99 320

Re: Another Stinky Coach

Reply #17 –
On my 91 U300 I see one under the kitchen sink . I have 2 Tee vents coming through the roof just above the bathroom. I can see a pipe in the closet behind the toilet that goes up through the roof and there is another about where the bathroom sink is that comes through the roof.Would there be another vent behind the wall between the bedroom closet and the bathroom sink? Heck I'm replacing at least the one under the kitchen sink just to see if it fixes my intermitent stinky issue
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: Another Stinky Coach

Reply #18 –
Quote
Would there be another vent behind the wall between the bedroom closet and the bathroom sink?
Different plumbing. I have four: under kitchen sink, behind toilet and two in the closet. All are joined and exit to the roof above the closet.
jor
93 225
95 300
97 270
99 320