Help with replacing pressurized fresh water tank

[glang58]

Hi all. First post from a long time lurker. I have what I assume is the original pressurized aluminum water tank (cylindrical, approx. 12" x 55") in a 1960 Overlander that needs replacement. In searching posts here, I see where some have had stainless steel tanks custom built and others have gone the plastic/on-demand pump route. I prefer the pressurized system because I'm familiar with it, and don't really need additional capacity for my use.

I'm not familiar with the on-demand system. I would very much appreciate price comparison between a new stainless pressure tank and the plastic on-demand type replacement. Also, if changing to a plastic tank is best, could someone describe the steps or refer me to a link or other resource that would enable me to do it myself? I'm concerned, for example, as to how I would connect a new style tank to the existing fill system. Would drain and supply lines need to be relocated, etc. Thank you in advance for sharing your expertise.

[Inland RV Center, In]

Originally Posted by glang58@comc

Hi all. First post from a long time lurker. I have what I assume is the original pressurized aluminum water tank (cylindrical, approx. 12" x 55") in a 1960 Overlander that needs replacement. In searching posts here, I see where some have had stainless steel tanks custom built and others have gone the plastic/on-demand pump route. I prefer the pressurized system because I'm familiar with it, and don't really need additional capacity for my use.

I'm not familiar with the on-demand system. I would very much appreciate price comparison between a new stainless pressure tank and the plastic on-demand type replacement. Also, if changing to a plastic tank is best, could someone describe the steps or refer me to a link or other resource that would enable me to do it myself? I'm concerned, for example, as to how I would connect a new style tank to the existing fill system. Would drain and supply lines need to be relocated, etc. Thank you in advance for sharing your expertise.

Converting to a demand system, is the only way to go.

Yes, it will cost a little more, but the benefits are much greater.

You basically need a plastic tank, a water pump, 2 check valves, a water fill inlet, all of which we have, along with instructions.

The tank is for the 64 to 67 trailers. Water pumps vary from real cheap, to rather expensive.

Andy

[overlander63]

Welcome to the forums.
We removed the leaking steel tank (most of them I have seen were steel, not aluminum, and very heavy), and installed a plastic tank, with an on-demand pump. I got a salvaged tank from a slightly used motor home, but it was pure luck I found one. Your best bet would be getting a new tank, and I would take a look at the Flo-Jet 2.9 GPM 12v pump. It has a check valve to keep the water from filling the tank when hooked to city water, so you only need to get one other check valve. It has the added advantage of being inexpensive. The tank I wound up with was a 15 gallon, and fit most of our needs.

[markdoane]

glang58,

Welcome to the airforums.

I've replaced my aluminum tank with a plastic on demand system. I still have the aluminum tank, but you would need to come out to minnesota to pick it up. Also, you would need to figure out how to get remove the stub end of the aluminum fill tube.

I sawed off the fill tube and re-used it as the fill tube for my plastic tank. I also moved it to the streetside, where the CB radio antenna was originally mounted. I put an overflow vent where the fill tube was originally located. A vent is one of the things you will need to add if you go to a plastic tank, both for overfill protection, and to allow air in as you empty the tank.

I believe the 28 gal tank cost $200 and the pump another $200.

[65CV]

glang58-

This thread may help if you decide to go non-pressurized.

http://www.airforums.com/forums/f443...tem-38564.html

John

[mustang]

Hello and welcome. You might be able to find a tank from a camper place that takes in wrecked units. Most camper places have this type of unit mostly old truck campers or popups. You might be able to get a recently replaced pump out of it. Surflo is what I purchased and is reliable as probably all are equal. I personaly would go with on demand as opposed to pressureized. I think you will agree when swap is complete. Dont forget to put a switchin the power lead of the pump. It should come with a built in regulator to hold pressure without burning up the unit. Good Luck on you choice.

[mustang]

also at the bottom of this thread you will get related threads. many older and will apply to your situation.

[volvophile]

I came across this thread while researching the same problem in our newly -ahem- self-cleaning Avion. The only thing I havent replaced/rebuilt on the fresh water side was the preasure tank. I really like the system. Its simple, mostly quiet, and I can charge it with a bicycle pump if the battery goes kaput.
Mines Aluminum, and appears to have developed a crack and one of the feet. (Im going by brail, since I havent pulled the tank yet)
I know aluminum is difficult to weld, but has anyone had any luck in getting one of these repaired?

[Inland RV Center, In]

Originally Posted by volvophile

I came across this thread while researching the same problem in our newly -ahem- self-cleaning Avion. The only thing I havent replaced/rebuilt on the fresh water side was the preasure tank. I really like the system. Its simple, mostly quiet, and I can charge it with a bicycle pump if the battery goes kaput.
Mines Aluminum, and appears to have developed a crack and one of the feet. (Im going by brail, since I havent pulled the tank yet)
I know aluminum is difficult to weld, but has anyone had any luck in getting one of these repaired?

Aluminum water tanks, have a "HUGE" problem of corroding on the inside.

Usually, if you attempt to repair one hole, you open up several more.

Ask the hundreds of owners that tried to repair a water heater tank.

It's a waste of time, effort and money, and if you were successful in repairing it, the repairs are short lived, at best.

Andy

[volvophile]

Hm, thats a good point. I can easily see it turn into a game of whack-a-mole with repairing the sucsessive leaks. I might have to bight the bullet on this one and go with a demand pump and plastic tank.

[Lumatic]

I have not yet started work on my 62. It has 2 original steel tanks, one up front and one amidships. I will probably switch to a demand system. Everyone says it's the way to go. When I get around to replacement, should I go above or below the floor?

[Inland RV Center, In]

Originally Posted by Lumatic

I have not yet started work on my 62. It has 2 original steel tanks, one up front and one amidships. I will probably switch to a demand system. Everyone says it's the way to go. When I get around to replacement, should I go above or below the floor?

62's have a smaller chassis than later trailers.

The smallest (vertically) water tanks that are available are 5 inches thick. That would make the tank be lower than the underbelly.

We have the 70's water tank that's 50 gallons, but you would have to create a solid mounting platform for it.

You can replace the two tanks you have, with 30 gallon tanks on the inside of the trailer. That tank was used from 64 to 67 and we have those too.

Changing out to a demand system simply means changing the fill neck, adding 2 check valves and a water pump.

Andy

[glang58]

Thanks to everyone for their input. I now have the tank out and found two dime sized ragged holes in the bottom near where the clamp strap passes on the right side. I also see several other suspect locations on the bottom of the tank that look like they are trying to corrode through so repair isn't an option. I'm still reluctant to go to on-demand since everything else in the plumbing system is working well.

Andy, you say going to on-demand involves a pump, two check valves and changing the filler neck, but don't I also need a vent/overfill that would involve putting another hole in the skin of the trailer? I don't like cutting holes if I can avoid it. Does anyone have a source they can recommend for a stainless replacement tank or know another way to skin the cat and keep a pressurized system? Thanks again!

[Inland RV Center, In]

Originally Posted by glang58@comc

Andy, you say going to on-demand involves a pump, two check valves and changing the filler neck, but don't I also need a vent/overfill that would involve putting another hole in the skin of the trailer? I don't like cutting holes if I can avoid it. Does anyone have a source they can recommend for a stainless replacement tank or know another way to skin the cat and keep a pressurized system? Thanks again!

You can simply drill a 1/8 inch hole in the filler cap you now have, for venting a plastic tank.

Andy

[Tinsel Loaf]

I have had several custom made stainless tanks over the years and everything came out perfect. Draw your design or take your old tank to your local steel fabricator. Do you want to increase the size of your tank or can you? Ask your local fire department where they take their stuff for repair or have custom parts made. You most likely will want a 916 stainless round tank with a concave bottom and top, if you want lot’s of pressure. The fabricating shop will most likely have a form for making the ends and it only takes a few minutes to make em. Have brackets welded to the tank to mount your pump vibration isolators. Have the holes cut and your stainless fittings of your choice welded to the tank and the mounting brackets. It will be the last water tank you will ever need for your Airstream. The six tanks I had built are still going strong after ten years in commercial service. Over time it will pay for itself. theGood luck.