In need of "fresh air"


New Member
We are new to the RV world. We have a 1976 Holiday Rambler 3000 and no idea, except by trial and error, of how things work. Of course we purchased this (temp. home) used and there wasn't any manuals to help out. Hope you don't mind the questions. How do we maintain the vent in the bathroom? We finally got the tanks to drain (thanks scooter) and now we keep dealing with the horrible smell, especially when the wind blows (outside, not inside :laugh: )
Any help would be greatly appreciated!!!


RE: In need of "fresh air"

are u talking about the over head roof vent or the sewer vent????
and bty welcome to the forum .. :approve: :)


Senior Member
Re: In need of "fresh air"

If you get the smell when the toilet valve is open, then the vent is a suspect. It may be plugged, or especially if the problem occurs when the wind is blowing you may have lost the cap off the vent.

If you get the smell when the toilet valve is closed, I'm thinking the vent may not be the problem. I vaguely recall hearing about some kind of gizmo on the toilet which if it dries out lets smell out. Then there is often a vaccum breaker under the sink which when it fails lets gray tank oder.

Also, it is a good idea to clean your tank really well to start with, and every so often thereafter. Don't just drain it, but flush it, repeatedly. Some Calgon water softener and Dawn dishwashing soap sloshing around in there while your are driving can help clean it too.


Senior Member
Re: In need of "fresh air"

I highly suspect that if you look under the sink, you will find a line from your sink drain that turns up toward the sink and which has a cap like device on the end with slotted openings on it. That is a vacuum breaker to allow for proper draining of the sink and tub. It is there to allow air to enter the line as the water goes past into the tank and it should close to prevent a back-flow of air from the tank into the RV. The things do fail as there is a small rubber diaphragm that is supposed to open as the sink drains and then to close to keep wind from pushing air into the tanks from the vent lines on the roof and then into the RV.

What is probably happening is that you have vent lines from the tanks to the roof and wind does at times cause a back pressure into the tanks. The problem tank is the gray water tank which can smell as bad or worse than the black tank, due to grease from the kitchen and oils from the bath. That diaphragm is probably not sealing and needs to be replaced. Just reach up and it should unscrew, by hand. Take it with you to any Lowe's or Home Depot and they will have a replacement as they are also used in stick houses. It will cost less than $5. When you install the new one, coat the threads lightly with a layer of Vaseline petroleum jelly to aid in sealing and then just screw it on snug. I'd bet this will make a big difference!


New Member
Re: In need of "fresh air"

The lack of the cap/cover on the pipe on the roof may be the culprit.

WM has a cap for the pipe called the shark(because of the was it is shaped) at about $12-13. Works like a weather vane. When the wind blows thru it help pull the bad air out. So no mater which way the breeze blows it spins to catch it.

Saw them first at CW for $23-25.

Darlin :cool: