Hidden Black tank valve

[Habu77]

I am just wondering if this extra valve phenomenon also occurs on the Hurricane 35M...

[pavemike]

Originally Posted by Habu77

I am just wondering if this extra valve phenomenon also occurs on the Hurricane 35M...

I doubt it. It is on the Vegas/Axis coaches. I have never seen it on ACE, Hurricane or Windsport. But, I would take a look to be sure. The only thing consistent on RVs is that nothing stays consistent.

[Golfbum18]

Originally Posted by pavemike

I doubt it. It is on the Vegas/Axis coaches. I have never seen it on ACE, Hurricane or Windsport. But, I would take a look to be sure. The only thing consistent on RVs is that nothing stays consistent.

If it's on a 29M it's really well hidden.

[Cabinetmkr]

I’m confused about the 3rd valve ...
if it’s closed, how is there any storage capacity at all? We have an occasional smell ..., I’m thinking the pipe from toilet to holding tank is too long and water and solids not reaching tank ??

[Cabinetmkr]

Originally Posted by cavie

You have a gray tank. a galley tank and a black tank. Or 1 black and 2 gray.

So you had a 2nd tank? Where was the waste coming from that was behind this hidden valve?

[pavemike]

Originally Posted by Cabinetmkr

I’m confused about the 3rd valve ...
if it’s closed, how is there any storage capacity at all? We have an occasional smell ..., I’m thinking the pipe from toilet to holding tank is too long and water and solids not reaching tank ??

The Vegas/Axis models have 1 grey tank and 1 black tank. The black tank has 2 valves, one being underneath the rear end of the coach but only a short distance from the valve in the dump compartment. Some larger model coaches have 2 grey tanks, usually one for the kitchen and one for the shower(s).

[Cabinetmkr]

Originally Posted by pavemike

The Vegas/Axis models have 1 grey tank and 1 black tank. The black tank has 2 valves, one being underneath the rear end of the coach but only a short distance from the valve in the dump compartment. Some larger model coaches have 2 grey tanks, usually one for the kitchen and one for the shower(s).

Sorry , pavemike , still confusing...
is the 2nd valve under the MH .. meaning you have to crawl ... ?? How many valves between toilet and dump valve? Is black tank split into 2 smaller tanks ?

[Oldchief]

On the Axis/Vegas models that have the toilet on the passenger side and all the way in the back of the coach, there is usually a second or "hidden" black tank valve. To operate it, you have to kneel down and reach under the rear of the coach to pull it open or shut. I bought a $1 foam pad garden kneeler at Walmart that makes kneeling much easier on my old, beatup knees. This second valve is intended to keep all the pressure from a full black tank away from the fairly long run of pipe to the 'wet bay', where your regular gray and black dump valves are located. I learned 'the hard way' that when you're ready to dump your black tank, its best to open your regular regular black valve first, then open the 2nd or "hidden valve".
My lesson on this matter came at a dump station, where, thanks to Thor's often mentioned poor quality construction, the pipe from the black tank separated from the regular dump valve and sprayed the very nasty and stinky black tank contents EVERYWHERE! This pipe separated from the black dump valve because it was not properly cemented and was just stuck in to the regular black dump valve. When I was pulling the 'hidden valve', without first having opened the regular black dump valve, all that pressure from the black holding tank was slamming in to the closed regular black valve. And, the whole thing finally fell apart. I was able to rebuild the entire black water system and used plenty of cement on all the joints, as should have been done by Thor, when our unit was built. So, to avoid this stinky problem, when dumping your black tank, open the regular black valve first, then open the "hidden valve", so everything will flow thru the system and directly in to the dump station's sewage system.

[Bob Denman]

Yup! No crawling: just getting one knee a bit dirty...
If you're worried about "stuff" accumulating in the crossover: you could always fashion a sprayer, and stuff it down the toilet every once in a while.

[JeffGolden]

My 2014 28z Thor Motor coach has the passenger side blackwater dump.
After laying under coach,I figured out the reasons for it.keep solid mater out of line where it can plug it up. The black water tank heater is on passenger side. Keeps the line from freezing.

[Bob Denman]

Welcome to the forum!
Since your first post is about "crap": things can only get better.

[Georgia Peach]

Originally Posted by JeffGolden

My 2014 28z Thor Motor coach has the passenger side blackwater dump.
After laying under coach,I figured out the reasons for it.keep solid mater out of line where it can plug it up. The black water tank heater is on passenger side. Keeps the line from freezing.

Are you Jeff Golden from Oregon? Formerly Faith Community? If so, well WOW!

[ducksface]

https://www.amazon.com/Barker-24130-...8110448&sr=8-3

The cure for the crawl.
Either link depending on ability.

https://www.amazon.com/Valterra-TX36...8110514&sr=8-3

Below.is for those buying a new rv.

[kbatschke@gmail.com]

Our Chateau 2020 28Z has the bathroom/shower on the passenger side. Like many here, our dealer did not point this out during the delivery walk through. Just the black/grey at the outlet. Fortunately, I noticed the valve because it had been left open by the dealer when checking tire pressure. Took me a little thought to decide which black valve to open first but it makes sense as has been noted to open the outlet black and then the valve just below the tank. No backing up in the under carriage sewer pipe.

[Wandering Woods]

I just found our extra valve on our 2018 Axis. The dealer left it open. We are on our 1st trip. Should I close it?

[Bob Denman]

It's always a good idea to keep that tank's valves closed until you're ready to dump it...

[BigD]

We camped with the extra valve open for more than a year until we found out about it. Our dealer had left it open also. Now we keep it closed until we dump and we follow Old Chief's warning above to open the regular valve first then the extra valve in the back.

[Wandering Woods]

Thanks