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Safari Tim · 07-02-2006, 11:22 PM

I will be adding a grey tank to my '60 Ambassador. I have a few questions about it.

1. Venting. There is currently no venting for the drain lines on the trailer. This will make it interesting to make a vent for the new grey tank. I remember my '71 having a vent for the black tank, kitchen sink and bathroom sink. How can I add a vent for the grey tank w/o going through the roof?

2. Due to space between frame members, I will be having tandem tanks. Do I have to vent each one seperately, or since they will have an interconnecting tube is one vent sufficeint?

3. Where does the water inlet to the grey tank have to be located on the tank? Does it have to be on the top, on the side but located high, or does not matter?

4. On my '60 Ambassador, I had to remove the last bit of belly pan to expose the rusted main frame rail near the bumper for repair. It turns out the the grey drain lines from both sinks go to the dump valve and a seperate drain from the tub goes to a different connection at the dump valve. So all my drains are conviently located in this area just behind the bumper. I know we always talk about adding grey tanks near the axel. But since I have this area open and will likely open the area ajacent to it for a tandem grey tank, would it be ok to mount a tank there? The one in the last cavity near the bumper would be about 13 gallons and the tandem tank in the next cavity forward would be about 15 gallons. I could have the frame strengthened while getting the other parts repaired.

Well, those are my thoughts for now, more to come

scottanlily · 07-02-2006, 11:40 PM

Hey Safari tim ,

That shower drain can be removed by using a tool for most all tub drain fittings ,the chrome thing in the tub .I removed mine and had it glassbeeaded/blasted of all corrosion ,then used marine resin ,like the fiberglass kind , and coated the whole piece right away to prevent corrosion.
It is designed as a trap inside to hold water inside to prevent sewer gases
from coming up the shower ,its special because it is very lowprofile and it
works like a P trap in design ,don't throw it out unless you want newer
plumbing hanging down under the trailer more than that does by at least 3 or 4 " .You gettin it done I see!!

scott

Safari Tim · 07-02-2006, 11:47 PM

Thanks Scott.

I wasn't planning on taking it out. I'll just take the hose off it and run it directly into a grey tank that I was thinking of putting into the same cavity space.

I might as well wire brush and por it though since I'm in there.

markdoane · 07-03-2006, 08:42 AM

Tim,

1. I would recommend vents from the grey tank through the roof. I would try to run these up through the side walls as there is more clearance between the inner and outer skins. The clearance between the segments and the interior fiberglass end caps can be less than 1".

You might try using AAV (air admittance valve), but I that will only solve the problem of letting air into the tanks while emptying. It does not solve the problem of how to let air out of the system while filling.

You could surface mount the vents if you like.

2. You will need a vent for each tank.

3. Doesn't matter where the inlet is located. A top entry will reduce hydraulic motion while you are driving, especially if the tank is only partly full. You definitely don't want to drive with the tanks full if they are located in the rear.

4. Be careful about how you handle routing the tub drain into the greytank. If the entry is fore or aft of the tank, you might have geysering of water into the tub during stopping or starting, or when going up or down steep inclines.

A side entry would be less likely to create a problem.

**azflycaster** · 07-03-2006, 09:00 AM

Tim,
The vents not only vent, but they also act as a vacuum break. They are located close to the traps for the sinks to prevent the water from being sucked out of the trap. The water in the trap is what prevents the sewer gasses from backing up into the trailer.
I was looking at the diagram for my 75 TW (rear bath) and it looks like the tank has one input line (on top) which is also the tank vent. All of the bathroom vents (vacuum breaks) tie into this vent line as well as the black tank vent. This vent line is located in a closet in the bathroom. An additional vent exists towards the front of the trailer for the kitchen sinks.

SmokelessJoe · 07-03-2006, 12:24 PM

Tim:

10 or 15 gallons is not very much capacity for grey.

If you locate a tank near or between the axles, like in contemporary Airstreams, the trailer will ride and last better and you can have 35 gallons or more of storage.

Taking off a couple more pieces of belly pan will reveal how you can re-plumb.

You should vent to the roof.

Here are some pictures that I’ve taken for you of the venting in my 1976 Argosy. Your trailer may be similar.

Standard 1-1/2” ABS drain won’t fit between the skins, which are less than 2” apart.

Airstream “flattened” the pipe that runs up the wall, probably by heating and pounding it into the oblong shape that you will notice.

Shown is the stack that runs from the grey tank, serves to drain and vent the kitchen sink en-route, and exits out the roof.

I have the original 10 gallon black and 12 gallon grey from this trailer. They are in very good condition.

I also have a brand new, never used, 36-gallon holding tank.

If any of them might help you, contact me.

Sergei

Safari Tim · 07-03-2006, 04:01 PM

Thanks everyone.

So it looks like I'll be adding a vent to the rooftop. I can go through one of the rear closets out the top, much the way my '71 did. I won't have to mess with running it inside the walls.

I just wonder why there is not a vent for the two sink drains.

markdoane · 07-03-2006, 04:48 PM

Tim,

Sinks don't need to be vented. Tanks need to be vented.

If the tank isn't vented, then the sink need to do double duty, as a drain and
a vent.

That's why the traps get sucked empty when the venting isn't right. It's the sink trying to be a substitute for the vent.

Chuck · 07-04-2006, 06:44 AM

In a house, the sink needs a vent...if the drain goes directly to the tank, it could still suck the water out of the p-trap...then you'll get fumes from the grey tank. not as big an issue as the black tank, but I understand can still get stinky.
If you put the tank up closer to the axles, you may be able to get the sink drain to go into the tank from the top, and vent both the sink and the tank at the same time, if you can hide a stack up through the roof somewhere along that line. (don't know the layout, or if there's a closet somewhere in there where you can hide it).

you could use 2 tanks and connect them with a pipe, but both tanks will need a vent to let the air out. otherwise, water will enter the second tank up to the level of that connector pipe, then it won't fill any higher, because the bubble of air trapped in there will prevent any more filling.

john hd · 07-04-2006, 06:49 AM

tim

you can use a "nova" vent for your sink.

quite a few trailers have them, mine included. i can attach a pic if you need one.

john

john hd · 07-04-2006, 06:55 AM

five mins. on google found the manufacturer....

http://www.studor.com/

john

Safari Tim · 07-04-2006, 09:01 AM

Good information guys. Thanks.

Looks like I will be adding vent piping for the tanks/sinks etc. going up through closets where I can.

Always wanted to be a plumber ;-)

scottanlily · 07-05-2006, 12:37 AM

Tim the blue 15 gallon tote we use fills up fast after a couple showers .Im gonna have to upgrade ,I love a hot shower .your grey tanks need to be at least 20 gallons .Remember, unless full hookups ,you will need a tote to drain the grey or pull the trailer to the dump station.possibly before your ready.If my tote is full I take it over to the dump and so on .Trailer stays put.You don't want all that water weight at the rear period ,don't do it ,your frame will not like it .

Scott

bryanl · 07-05-2006, 08:20 AM

Your sink and tub and other gray water producing devices should already have vents. That's to get the waste down the drain. But then you need to get it to the tank and that's why there is a need for a tank vent.

One guy at the I'Rally used a run of 3" pipe under the trailer for his gray tank. Since he had sink and tub on opposite sides of the trailer, he was able to tap them into his gray water storage on each side to provide 'tank' venting for the other side. This means the waste drop into the gray tank must be above fluid levels.

Chuck · 07-05-2006, 08:34 AM

Quote:

Originally Posted by scottanlily

Tim the blue 15 gallon tote we use fills up fast after a couple showers ....your grey tanks need to be at least 20 gallons.

I think he meant that he would use 2 tanks of that size, for a total of 25-30 gallons.

Quote:

Originally Posted by scottanlily

You don't want all that water weight at the rear period ,don't do it ,your frame will not like it .

This has been pointed out quite a bit in the past, and I'm sure its a problem.
What never seems to be discussed, (and Tim, this would be a great topic of discussion for your show), is how this can be overcome. What, if anything, can be done to make it so that your frame WILL like it? Add more steel? where? box the frame? weld another c-channel under the existing one? add more cross-members? reinforce the frame-to-shell connections (how?) Whether its tanks or a spare tire or bicycle rack or whatever, it seems that lots of us would like to add some heavy stuff back there. And since in many cases, the frame is being repaired or altered in some fashion, anyway, might as well make these changes while we've got the whole thing opened up.

Safari Tim · 07-05-2006, 09:58 AM

Yep, that was the idea, two tanks to make up around 25-30 gallons. My frame rails are 4" so I just did some quick math and came up with needing two tanks in two seperate cavities in the frame. I'll check closely when I decide where to mount one.

My frame is already boxed in, so that should be good. I need to take it to the welder to have the rusted through parts repaired and was thinking if I could add some more strength to locate the tank near the rear.

The axles seem pretty far back on my Ambassador.

SmokelessJoe · 07-05-2006, 10:52 AM

Tim:

If you move your tank to near or between the axles, size and weight are not so much an issue.

An good example is this placement on a brand new Safari.

Sergei

markdoane · 07-05-2006, 11:20 AM

Tim,

If you locate the tank forward of the axles, it doesn't matter if it hangs down a little (3+ inches) . I put a 28 gal tank in my '59, and I don't worry about things getting knocked off because it's within the approach angle of the hitch and tires.

It also locates the two tank vents in a closet, and under the kitchen sink.

Just a friendly suggestion. It's your baby.

Safari Tim · 07-05-2006, 02:52 PM

Makes good sense. I cannot have anything lower on the back of the trailer because I can barely make my driveway approach as it is.

Putting together a draining setup back there will be a challange. Expecially since the black tank is on the curb side and that is where the original dump connection is.

As of my other thread, *Toilet won't budge* I'm getting deeper into this trailer than I first intended. I'll be replumbing everything including drain lines so I might as well move the grey tank toward the axles.

So what you're saying Mark & Sergei, is to let the tank drop a few inches below the belly pan to gain more tank capacity?

markdoane · 07-05-2006, 03:19 PM

Quote:

Originally Posted by Safari Tim

So what you're saying Mark & Sergei, is to let the tank drop a few inches below the belly pan to gain more tank capacity?

That was my take on it, but everybody's ideas are different. I would only do something like this as part of a complete frame-out rehab. Otherwise it's a lot of work.

I plan to leave the blackwater tank in the rear, and use a macerator pump to move the stuff forward and have it discharge just ahead of the streetside wheel, near where the graywater tank outlet is located. There will also be a manual valve on the blackwater tank, in case of a macerator pump failure. The macerator will fit inside the bellypan, so I will only have the manual valve cap protruding below the skin.

Here's a picture of the outlet of the graywater tank. I built an insulated fiberglass cover to protect it from road hazards, not shown.