Where to place/build the fresh water tank

[josephpearce]

Thanks to everyone on this forum, this is my first time posting and following others travails has help me this far:

Me and girlfriend purchased a 26' overlander, gutted it, removed all the inner panels, raised the shell, pulled out the chassis and have removed all the old flooring. We need to re-weld some of the frame to get the frame back in good shape, but otherwise it looks good. It did not have a clean water tank and so it is up to us to install one as well as a new grey/black combo. A couple questions for those who have been there

* I suppose one wants to keep the tongue weight to nearly zero so I could try to calculate the center of gravity to be between the dual axles after I put in the avg weight of the tanks, weight of the appliances, bed, etc.. this would take some time. Is there a general rule of thumb about placement distances from the axel?

* I want to keep the tanks below the floor, this leaves a very shallow space ~4" Getting a suitable stock tank to fit well would seem difficult. I am not bad at composites (in fact planning to do the entire interior in different composites) so I could make them. Is this what most people do, get some custom job or put them above the floor line?

* For the pump, I suppose it has to be nearly hugging the belly pan to avoid it sucking as little air as possible. (?)

Thanks
Joseph Pearce & Jessica Prentiss

[Sixty3TW4US]

Welcome to the forums and congrats on your "65" Overlander. You have some important questions, i'm sure you will get some help from other overlander owners. As far as the tongue weight, i don't know the exact weight but it will be far from zero. Like a few hundered lbs, mabey 300 to 600 lbs. I believe my 24' Tradewinds hitch weight is around 350-450 lbs.

Good luck

[azflycaster]

Welcome to the forums.
The hitch weight should be around 12% to 15% the weight of the trailer. Light hitch weight will cause sway problems when you tow. Your trailer was originally 3900 lbs dry with a hitch weight of 440 lbs or 11%. Once you add fresh water and propane the number will go up.

[azflycaster]

I would advise against a black/grey water combo tank. Many places you can drain the grey on to the ground, but never the black. Also when the tank fills up, it will normally back up into the shower. Grey water sitting in the shower is bad enough. In my opinion, two separate tanks would be the preferred way to go.

[FLYNCLD]

Greetings Joseph & Jessica,

Welcome to the Forums and the Airstream life! We are doing a reconstruction on a 1962 22' Flying Cloud, and have posted some ideas to our blog that may be of some use to you. You can find them here:

http://www.airforums.com/forums/blog...6-flyncld.html

In one of the pictures on the first blog posting, you will see the front end of the gutted trailer and if you look carefully you can see where the water tank/pump is located. This seems to work pretty well. We also have installed a separate gray tank and you can see how we handled that. We are using a composting toilet, so we have removed the black tank that was in the trailer. It might work for you, so you might want to take a look at it here:

Airstream Trailer & Motorhome Classifieds - Original Black Tank 1962 Flying Cloud - Powered by PhotoPost Classifieds

We also have a stove and a few other items you can see there as well. Hope this helps, and good luck with your project!

FLYNCLD

[purman]

Our friends have a combined black/grey on the '04 AS they haven't had it back up, but they sure keep an eye on it. The black tank can just be for the tolit so it doesn't have to be very big 12 to 20 gals is plenty.

I put a new 40 gal fresh in mine under the front coach where the old 30 gal was. I don't travel with full tank of water. why hual all that weight unless you are boon docking.

My old fresh tank is destined to become my grey tank. It will go between the axels under the frame. It only hangs down 6" so it should be just fine.

[josephpearce]

Thanks for all the responses!
Flyncld I see in your pics the grey tank is bellow the belly skins. Is this common dropping one of the tanks through the belly pan? I see no problem with it except for slightly greater chance of road debris causing damage.
azflycaster, I am confused on what advantage there is on two separate tanks vs one large tank that is sectioned off to have one black and one grey. If grey water overflow is a problem then I should size the grey tank to be some X% bigger than the black. Speaking of which is there a rule of thumb on the size of grey vs black tanks 50% bigger etc..

Thanks again
Joseph Pearce & Jessica Prentiss

BTW I have started to post some of the pics at
Picasa Web Albums - jcpearce - airstream
The floor is a little more cleaned up (or ripped up ) since the most recent photo. Going to continue on that today, hopefully to get it in a state to weld in 3-4 days.

[FLYNCLD]

There has been much debate on the subject of having the tank below the belly line. As ours is nestled behind the axle, and made of pretty tough stuff, I think the odds of a direct strike from road debris that would cause actual damage is minimal, but certainly not impossible. Time will tell! The tank I found is such a tight fit that a small bead of silicone was all that was needed to finish sealing the tank against any moisture or critters. As for dragging the tank going in or out of gas stations etc., this is probably my biggest concern, although once again it is right behind the axles, and it would be much more likely to drag if it was farther back. I intend to be careful! I will keep the forum posted once we get this thing on the road again and subject it to real life conditions

FLYNCLD

[josephpearce]

Given I am decent in composites I was thinking of building my own water and black water tanks, was it the standard fittings?

* For the fresh water tank I see the water pump I ordered takes 1/2, fittings so I was thinking of running 1/2 PEX. For the breather hose I assume I can use 1/2" PEX, for the line to fill it?

*For the black water tank, I assume I cut out the dimensions for the toilet to mount to. Use a 1/2" breather hose (too small?). For the outlet do I need a three inch fitting such as Uniseal Slip Fittings
I read somewhere about the waste water tank drain line screwing on, and it appears from the link above it is just a straight tube that comes out. Is there some other kind of fitting? And do I need another fitting where I ran rinse it out, or just use the same line that it drains from?

*For a grey water tank do I need another three inch outlet, or some smaller unit?


Many thanks again
Joseph & Jessica

[Silvertwinkie]

Airstream has had several frame re-designs from your model year to the current model year. My suggestion would be to replicate what the factory does now and place all the tanks near the axle areas in trailers of this size. However, I would make sure your frame is sufficient around the axles to handle the additional weight. You could find that you may have to do some frame enhancements to handle the weights there were not present at the time of your units original manufacture.