1975 Tradewind - grey tank removal?

[Torii]

I have a 1975 Tradewind. Whenever the grey tank reaches about 1/2 capacity water starts pouring out of the under belly at the rear of the trailer. I am assuming that there a crack in either the tank itself or the plumbing somewhere. I have the Airstream Manual which nicely illustrates the plumbing system and I have removed the belly skin at the rear. I cannot seem to figure out where the leak is at so my next thought is that I will need to remove the gray tank so I can have a closer look. As best as I can tell this involves cutting all the ABS drain pipes that go to the tank, disssconecting the shower drain flange, removing the support bars underneath the tank and then dropping it down. I am wondering if anyone else here has done this job on a 75 tradewind before and if so, is there anything I should know before doing this...

-T

[SmokelessJoe]

T Man:


We have removed and replaced with new both the black and grey on my 1976 Argosy.

The procedure is essentially what you propose.

But, since you have the belly pan off now, why don’t you first run water through the system to see if you can visually trace the leak?

Sergei

[Torii]

Originally Posted by SmokelessJoe

T Man:


We have removed and replaced with new both the black and grey on my 1976 Argosy.

The procedure is essentially what you propose.

But, since you have the belly pan off now, why don’t you first run water through the system to see if you can visually trace the leak?

Sergei

Sergei,

I did try that but was unable to see where it was coming from. I may try again before cutting though. Maybe with more lights and one of those long-handled mirrors I can pinpoint the leak.

[Torii]

Originally Posted by SmokelessJoe

We have removed and replaced with new both the black and grey on my 1976 Argosy.

The procedure is essentially what you propose.


Sergei

Sergei - My Tradewind is the mid-twin / rear bath model. Is that the same as your Argosy?

[SmokelessJoe]

Yes, exactly.

There was a 10 gallon BLACK right at the rear and a 12 gallon GREY just forward of that.

We’ve now installed a 14.5 gallon black at the rear and a 32 gallon grey behind the rear axle, right up tight to it.

Sergei

[Torii]

Originally Posted by SmokelessJoe

Yes, exactly.

There was a 10 gallon BLACK right at the rear and a 12 gallon GREY just forward of that.

We’ve now installed a 14.5 gallon black at the rear and a 32 gallon grey behind the rear axle, right up tight to it.

Sergei

Sergei

I was wondering what it it would take to put larger tanks in... Now that you have confirmed that it is possible I am thinking that would be better than repairing the existing tank. You don't happen to have any photos of the work you did do you? I'd be really interested in loooking at them if you do!

-T

[Chaplain Kent]

Originally Posted by T Man

Sergei

I was wondering what it it would take to put larger tanks in...

-T

Larger tanks mean more weight. Make sure you compensate for this additional weight somewhere, somehow.

[Torii]

Originally Posted by T Man

Sergei

I was wondering what it it would take to put larger tanks in... Now that you have confirmed that it is possible I am thinking that would be better than repairing the existing tank. You don't happen to have any photos of the work you did do you? I'd be really interested in loooking at them if you do!

-T

PS - Did you have to cut any of the frame to fit a 32 gallon gray behind the axle?

[SmokelessJoe]

T Man:

I have a drawing and photos and I will write in more detail later today.

Sergei

[dieterdog]

Sergei,, am awaiting your post . also wondering how to equalize the weight in the front portion of the trailer in order to compensate. donna

[Chuck]

Originally Posted by dieterdog

. also wondering how to equalize the weight in the front portion of the trailer in order to compensate. donna

don't think you really have to worry too much, with this sized trailer. the moment arm of the tanks is minimal...unlike the s t r e t c h units >28', where the rear of the trailer hangs back there so far behind the axles.

if you don't drive around w/ the tanks full, no problem at all.

replacing the univolt goes a long way, too. no, its not as heavy as a full tank of poop, but it is 40 lbs, as far aft as you can get in my trailer. a modern solid-state converter only weighs a couple of pounds.

[SmokelessJoe]

T and Donna:

Chuck, above, has got it right.

There is unlikely to be a weight or balance issue. As he says, we’d be better off to eliminate the weight of the old Univolt than worry about tank weights.

Modern day Airstreams usually have tanks in the neighborhood of 40 gallons EACH. They can do this because they locate them around the axles were the weight doesn’t matter as much.

In my case, we put a new 14.5 black at the rear where the 10-gallon original was. You can make the argument that’s 45% more but in absolute terms, it isn’t much weight gain in total.

In any case, people don’t usually haul their full tanks around so the weight issue gets exaggerated.

We moved the new grey (31.66 gallons instead of the old 12) forward, to just behind the rear axle.

T, if your tank is actually leaking you may be better off replacing than repairing. If it’s just a fitting or seal, you may avoid the cost and trouble with a simple repair.

If you do replace, you will want to consider going larger. Maybe you just want to go larger, period. I did.

We did not cut the frame rail per se but we did remove some cross members. These will be replaced or relocated when we finish up. The angle support system you make to hold the tank is a kind of strengthening cross member as well.

Once you get into doing something like this it is not as daunting as it first seemed.

I bought both tanks at Ameri-Kart in Indiana and can supply you with the contact number. They are a major manufacturer of RV tanks with about 200 sizes in their repertoire.

You find out what space you have available then hunt down a size that fits.

Or you can have a tank custom made to your exact measurements but that costs money, usually $500 or more. Ready made will run more like $150 to $200. I paid only $95.00 for the black. There are several sources right in California but I found them all more expensive than Ameri-Kart.

If I can figure out the photo system here I’ll attach a few photos of the work to date. The tanks in the photos are only propped up for a “dry fit”. In a day or two we will have the hanging done and I can post pictures of that.

I have a drawing of the layout that I can fax to you. PM me.

Sergei

[dieterdog]

Sergei,,, thank you so much for posting the pictures. will be so helpful in my future efforts to make the trailers function for longer trips,,,, appreciate your ground breaking innovations,,,, donna

[Chuck]

Sergei,
which tanks did you get? (model numbers, so I can look 'em up). your trailer probably isn't a whole lot different than mine...can't really tell from the pics exactly whats going on. was your original black tank below the floor? is that where you're putting the replacement?

I found ameri-kart's website, after you mentioned them before. looks like they have alot of models. (they never turned up in any google searches I did in the past, looking for tank manufacturers). still not easy to find ones that would fit inside the existing frame cavities, withough having to hang down below the belly pan, or just be too small to be worth the effort, imo. my frame cavities are 23"x5"x ~60-ish"...height and width seem to be be limiting numbers. don't think I can move x-members, either, as in or near the appropriate location, there are either floor joints requiring that support, or something else in the way. (shower drain, for example). One possibility I saw with one tank that is 8" deep...the 3" outlet would be just below the belly pan, so a drain pipe could be run on the outside.

[Torii]

Sergei -

Thanks so much for all the great info! The prospect of having a greater GREY water capacity is very tempting. This weekend I will get under the Tradewind and have another look with these ideas in mind.

Looking at those pictures it looks as though you re-located your thetford valves... Just as a point of reference, in the bottom right photo, is that hole in the floor where the shower drain comes down?

Thanks!

T

[SmokelessJoe]

Chuck and T Man:

The tanks are H488 32” x 54” x 6.75” for 31.66 gallons

and

H076 32 3/4” x 18” x 7.87” for 14.5 gallons.

My black was above the floor, under the toilet. The main tank was under that box that Airstream usually has in bathrooms with a kind of “snout” going through the floor to the drain outlet.

I didn’t like that throne on a box and moved the tank BELOW the floor.

The photos will be hard to understand. Lots of shop confusion around. Keep in mind the tanks are just propped in position, for fitting, etc.

I’ll try to explain them:

The first shows the darker black tank, propped on a box near the rear and the end of the grey at the top left of the photo.

Shown is the 3” Double Rotating Elbow where the 1 1/2” drain (left) meets the 3” sewage drain (right) at the central common outlet.

A Sani-Con macerator will permanently replace the cap on the outlet. The macerator hose, with grey water by-pass, will be stored here. The space between the two outriggers will be developed into a compartment with a closing door.

Next, the black tank in basic position.

Then, a head on front shot of the outlet described above. Note GREY handle to the left, BLACK to the right.

The Micro Pulse sensor heads will also be attached to the plumbing lines inside this compartment.

The last photo just shows what I’ve described from behind.

T Man, the hole you asked about is for the black vent to the roof. The photo is shot from under the trailer and behind the new common valve.

The plumbing has been completely relocated. The dump valve is now just to the rear of the rear wheel, street-side.

All materials are new including the VALTERRA main valve referred to above.

The photos were not taken to post but merely for a shop work record so they aren’t easy to understand. I’ve tried my best to explain.

It’s hard to find tanks that are right for the situation but you will if you search hard enough. There are hundreds of sizes and shapes floating around out there.

Getting them shallow enough is a problem. Mine will come below the belly pan but that is the case with contemporary Airstreams so. The box that holds the tank comes 5” to 7” below the belly pan on current models. You can do that at the axles but not at the rear.

It was also important for me to try to match the depth of the two tanks because one of the features of the Sani Con system is that you can “back-flush” the black with the grey water.

I hope this helps.


Sergei

[Chuck]

Originally Posted by SmokelessJoe

I didn’t like that throne on a box and moved the tank BELOW the floor.

"throne on a box"....I have that, too, but it doesn't bother me that much. my tank is 13 gallons. all that work for 1.5 extra doesn't seem worth it, to me, but you could probably go much bigger, still, under the floor. I think that a bigger problem with removing the "throne box" would be the modifications to the rest of the bathroom. If I were to upgrade the tank, I think I would make a dummy throne box out of plywood, use the same tank cover, and re-assemble the bathroom the same way it is now.

Originally Posted by SmokelessJoe

The photos were not taken to post but merely for a shop work record so they aren’t easy to understand. I’ve tried my best to explain.

yes, the explanation sums it all up. just an fyi...you can post bigger pics on the forum. it'll take up to 640x480. if you have windoze xp, you can download a free "power toy" from microsoft that makes picture resizing as easy as can be.

Originally Posted by SmokelessJoe

...The box that holds the tank comes 5” to 7” below the belly pan on current models. You can do that at the axles but not at the rear.

do you mean, "the other way around"?

Originally Posted by SmokelessJoe

It was also important for me to try to match the depth of the two tanks because one of the features of the Sani Con system is that you can “back-flush” the black with the grey water.

that sounds interesting. can you tell us more about it?

also...the innards of your trailer are more different from mine than I thought. seeing supports and metal thingies going every which-way under there threw me off. also looks like the main frame rails are much taller than on the early 70's airstreams. that cutout for the drain pipes: is that factory, or did you add that?

[SmokelessJoe]

Chuck:

I can understand your concern that removing a tank could result in too much modification to your bathroom but that wasn’t my situation.

I had determined to strip the whole interior out and redesign the area.

My new ceramic toilet will sit flat on the floor in a clean lined space and that’s what I wanted to achieve.

Finding a bigger tank for the available space might have been possible if I had looked even longer but 14.5 gallons is enough when one or two people use the coach. I don’t have a family full of kids trooping in and out to use the can all day.

Most people have a problem with the grey capacity, rarely the black.

Thanks for the tip on photo size. I will tell iPhoto to send in the larger size when I do it next.

I don’t understand “the other way around”

What I meant is that on present day Airstreams the insulated boxes that contain the holding tanks dip below the belly skin by 5” to 7”. That doesn’t matter near the axles but it would at the rear of the trailer.

The Sani-Con Waste management System can be seen at

http://www.emptythetanks.com/index.html


The manufacturer says it can “back-wash” your black with wastewater from the grey this way:

Open the black valve and push the start button. Macerator expels the black at 12 gallons per minute.
Shut motor off. Open grey valve. Soapy wastewater will immediately flood into the black tank.
Close grey valve, start motor. Waste water expelled from black.

This is repeatable depending on how much wastewater you have.

We also installed the No Fuss Flush device that is factory installed on modern Airstreams.

The Sani-Con has a 1” compressed coil hose that is 7’ long, extending up to 21’.

The macerator with grey water by-pass and hose, the drain valves and the Micro Pulse sensor heads will all be enclosed in a compartment with a closing door, conforming to the shape of the Argosy.

I don’t think the undercarriage is different from other Airstreams of the era. It will be very much like yours.

The main frame rail is a 5” C channel. 4” “axle mounting plates” are added so that the frame reaches approximately 9” in that area. There were also 4” plates used to hold the original tanks.

We enclosed some of the space between the plates.

We did the cut out for the main drain.

The tube stock beam running across the last photo is temporarily added by us just to hold the frame “true” while we modified or added cross members or supports.

Sergei

[Chuck]

Originally Posted by SmokelessJoe

....14.5 gallons is enough when one or two people use the coach.

yep, I think so, too. our 13g seem fine for the 2 of us, for a long weekend. but soon, there will be 3 of us. actually, there ARE 3 of us, but the little one still poops like an astronaut. (which is actually not such a bad thing, when you're camping. ). But that should be changing soon. and I'm just thinking that if I have to tear it all apart under there to do a grey tank, (of which I have none, at the moment), might as well do it all, and do it once.

Originally Posted by SmokelessJoe

I don’t understand “the other way around”

you said that current models can have a tank drop 5" below the belly pan AT the axles; my axles practically touch the belly pan. (in fact, I remember reading allignment procedures in the service manual state that you might have to actually cut into the belly pan so the axles can stick up in there, should the axle tube need to be bent that much to correct the allignment of the wheels). so there is no space to drop anything there. but there's nothing in the way at the back of the trailer. (?)

Originally Posted by SmokelessJoe

....
I don’t think the undercarriage is different from other Airstreams of the era. It will be very much like yours.

gotta remember, I have *no* grey tank at all. so no plates extending the frame at all, except for the axle mounting plates.
but that all makes sense, now, considering that you are upgrading something that was already there.

thanks for the link. I'll have to check that out.

[SmokelessJoe]

Chuck:

The photo below may help you understand what I meant about the tank projecting below the belly on current Airstreams.

(Incidentally, can anyone out there tell me what that round device on the belly pan is, the one that looks something like a door stop?)

You interpreted AT the axles as ABOVE the axles, I think. I mean in the area of the axles, up close to the front or rear axle.

Clearance and weight do not matter as much there.

There is about 30” BETWEEN the axles too but it would be difficult to run plumbing to a tank located there. The axles would get in the way.

If you install a grey water tank you can copy the techniques used on later or contemporary trailers. The frame you start out with should be basically the same.


Sergei