Complete replacement question

[jeremyrp]

I am doing a full rebuild of our 72. I just finished up the rear frame replacement and flooring now it’s time for the “crappy” part. When I look up plumbing schematics I find the basic layout but I never see anything about where the vent pipes (there were two running through the walls and out of the ceiling on ours) or anything about connecting tanks. Does anyone know of one that would let it out a bit better for me? I am good with almost every aspect of rebuilding this guy but I SUCK at plumbing. Thank you in advance.

[TheGreatleys]

Are you looking for the original plumbing schematic for your rig, or just some advise on how to construct your plumbing so that it works?

Every tank needs a vent, and every sink needs a trap with a vent behind it. My 74 had the fresh tank vent built into the fresh tank fill, a 1-1/2" vent under the kitchen sink, and a 1-1/2" vent in the wall of the rear bath that handled the tub, sink, gray tank, and black tank venting.

[jeremyrp]

Originally Posted by TheGreatleys

Are you looking for the original plumbing schematic for your rig, or just some advise on how to construct your plumbing so that it works?

Every tank needs a vent, and every sink needs a trap with a vent behind it. My 74 had the fresh tank vent built into the fresh tank fill, a 1-1/2" vent under the kitchen sink, and a 1-1/2" vent in the wall of the rear bath that handled the tub, sink, gray tank, and black tank venting.

Does the toilet have to be directly over the black tank or can I have a short 90 3”pipe going to it? The bathrooms going to be on the side of the AS.

[AlinCal]

Originally Posted by jeremyrp

Does the toilet have to be directly over the black tank or can I have a short 90 3”pipe going to it? The bathrooms going to be on the side of the AS.

You can make offsets but you must enter the top of the tank, when you flush the toilet the drain piping needs to completely drain and not become part of the tank(hold liquid).
That said a straight shot would be preferable and would use less water to flush.

[AlinCal]

To add to TheGreatleys post, yes you want/need a vent at each P trap to eliminate the possibilty of the trap siphoning dry. Those vents do not have to be piping run out the roof but can be air admittance valves or trailer vents as Ive always called them(several dif names).
Example https://www.zoro.com/oatey-sure-vent...iABEgJHOfD_BwE

[TheGreatleys]

Originally Posted by jeremyrp

Does the toilet have to be directly over the black tank or can I have a short 90 3”pipe going to it? The bathrooms going to be on the side of the AS.

If your toilet is not sitting on top of the tank, you would probably need a macerator pump to make it work, which adds some complexity.

I'd install the black tank directly under the toilet.

[jeremyrp]

Originally Posted by TheGreatleys

If your toilet is not sitting on top of the tank, you would probably need a macerator pump to make it work, which adds some complexity.

I'd install the black tank directly under the toilet.

That’s what I was afraid of.

[jeremyrp]

So in the picture I am to assume the pipe coming out of the tank would be a vent pipe and the female with the plug would be where the toilet bolts to the tank.

[AlinCal]

Sounds reasonable.

[TheGreatleys]

Originally Posted by jeremyrp

So in the picture I am to assume the pipe coming out of the tank would be a vent pipe and the female with the plug would be where the toilet bolts to the tank.Attachment 333458

Correct. Also ... do a search on this forum for "Airstream supply" and "silver trailer supply" before you send them any money. They receive frequent ... uh ... feedback.

[AlinCal]

Originally Posted by jeremyrp

So in the picture I am to assume the pipe coming out of the tank would be a vent pipe and the female with the plug would be where the toilet bolts to the tank.Attachment 333458

The toilet does not bolt up to the tank but to the toilet flange, I'm guessing your plug is threaded and there are a few ways to make that connection but here is one choice with the addition of a 3" threaded nipple.
https://www.google.com/search?q=3%22...hrome&ie=UTF-8

[jeremyrp]

That’s what I meant. Not that it bolts directly to it. Sorry about that. And so the other pipe is just the vent for the stankonia? LOL.

[jeremyrp]

Originally Posted by TheGreatleys

Correct. Also ... do a search on this forum for "Airstream supply" and "silver trailer supply" before you send them any money. They receive frequent ... uh ... feedback.

Will do. Thanks.

[AlinCal]

Originally Posted by jeremyrp

That’s what I meant. Not that it bolts directly to it. Sorry about that. And so the other pipe is just the vent for the stankonia? LOL.

Sorry I thought you may have meant otherwise.
The vent pipe also the tank to dump when you pull the drain valve.