Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Elliott on December 11, 2021, 03:21:46 pm
Title: Black tank vent cap removal
Post by: Elliott on December 11, 2021, 03:21:46 pm
I believe this vent behind the toilet is the culprit for the blank tank smell we occasionally get. How does one remove it? It looks like it may be a male threaded bit that screws into the female end of the pipe but it won't budge. Twisting the ribbed ring on the pipe also yields no results. I don't want to really crank on this thing until I know for sure.
Thanks in advance
Title: Re: Black tank vent cap removal
Post by: dsd on December 11, 2021, 03:43:35 pm
Its a studor valve. There is like three on board. They allow air into the vent system and close as neeeded. They get old. Just unscrew and replace. Double small pipe wrenches No need to be super tight. One in toilet area, under sink and one near water hook up for cloths washer. Double check the size Scott 1-1/2 inch Tuuber Vent 2x Superior Seal Air Admittance Valve - - Amazon.com (https://www.amazon.com/inch-Tuuber-Superior-Admittance-Valve/dp/B07N98QRY2/ref=sr_1_1_sspa?gclid=CjwKCAiAtdGNBhAmEiwAWxGcUkG7JZ-yt2Es2Xlb5JXqxRcAWHldNntVSIJbgiuyKHSSqCvQtQEZ3BoCZUYQAvD_BwE&hvadid=177769023330&hvdev=c&hvlocphy=9030802&hvnetw=g&hvqmt=e&hvrand=15876285170419178526&hvtargid=kwd-4124239862&hydadcr=1832_9900018&keywords=studor+mini-vent&qid=1639255323&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEzUFFQWllFWEs4S1dDJmVuY3J5cHRlZElkPUEwNjI4NDExMjNJTzdaUENaR01FUiZlbmNyeXB0ZWRBZElkPUEwNTkzMzg3MktVWUhHSkxBMVdKRyZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=)
Title: Re: Black tank vent cap removal
Post by: AC7880 on December 11, 2021, 04:29:52 pm
95% chance that studor valve is for the grey tank. The only black tank vavle is the roof vent.
I believe this vent behind the toilet is the culprit for the blank tank smell we occasionally get. How does one remove it? It looks like it may be a male threaded bit that screws into the female end of the pipe but it won't budge. Twisting the ribbed ring on the pipe also yields no results. I don't want to really crank on this thing until I know for sure.
Thanks in advance
You can grab that top part with channel locks. Pics at the link above of what they look like.
The white ones in the pic at the link are more money but won't fail in the future.
Sewer Odor, roof sewer vent, air admitance valves inside... (https://www.foreforums.com/index.php?topic=34106.msg312768#msg312768)
Title: Re: Black tank vent cap removal
Post by: AC7880 on December 11, 2021, 04:54:39 pm
I got it off with a pair of channel locks. Thanks guys
You have at least three - and up to 5 of these in the coach. Recommend changing them all. Kitchen sink, bath sink, shower (probably the one in your picture), and behind washer/dryer if you have a washer.
Title: Re: Black tank vent cap removal
Post by: Joe Phebus on December 11, 2021, 09:26:27 pm
Might be worth checking the roof vents and toilet seal as well. One of ours was installed wrong when we bought the coach (backwards). Replaced all the Studor valves and no go. The fixed that roof vent and replaced the toilet seal and problem was solved.
Title: Re: Black tank vent cap removal
Post by: juicesqueezer on December 11, 2021, 10:29:12 pm
I got it off with a pair of channel locks. Thanks guys
Elliot, no need to tighten these back on, just hand tight works! Found at any hardware, plumbing shop, Lowes or Home Depot. There are lots of prices on these and I recommend the ones for just under $8 bucks. No need to pay through the nose on these, it is a simple device and when not working, it stinks! lol, just a little humor there!
Title: Re: Black tank vent cap removal
Post by: Jack Lewis on December 13, 2021, 09:53:14 am
I replaced all of my air admittance valves (AAV) three years ago. The bad one was the one next to the kitchen sink, it is black in the before picture below.
The seal was wet and distorted. If the water level in the kitchen sink goes higher than the AAV, this is a no no, according to the instructions with the new valve. To me, that makes sense. When I replaced it I mounted it higher, as you can see in the photo below. I had to use a rubber plumbing connector, to get it up higher, and out, from the cabinet wall molding to clear the AAV.
Before picture: Shared album - John Lewis - Google Photos (https://photos.app.goo.gl/eXPpaoddvtE2xMrm7)
After picture: Shared album - John Lewis - Google Photos (https://photos.app.goo.gl/VJe5UJ37dYH3cvC79)
Title: Re: Black tank vent cap removal
Post by: Jack Lewis on December 14, 2021, 01:18:59 am
I replaced all of my air admittance valves (AAV) three years ago. The obvious bad one was next to the kitchen sink, it was black in the before picture below. It was wet and distorted. I replaced all, as the seals get hard, and are likely to leak air out, or seal, not allowing air in from the interior.
If the water level in the kitchen sink goes higher than the AAV, this is a no no, according to the instructions with the new valve. To me, that makes sense. When I replaced it I mounted it higher, as you can see in the photo below. I had to use a rubber plumbing connector, to get it up higher and as close as possible to the Corian counter top. This mounted it out and away from the cabinet wall molding. Before picture: Shared album - John Lewis - Google Photos (https://photos.app.goo.gl/eXPpaoddvtE2xMrm7) After picture: Shared album - John Lewis - Google Photos (https://photos.app.goo.gl/VJe5UJ37dYH3cvC79)