Visit our Popular Forums

Lumatic · 10-10-2015, 07:12 PM

I overfilled by tank a few months ago and think I popped a seam After living with it for a while the leak seems to be getting worse.

Should I crawl under there and replace the tank myself of have the local AS dealer do it, who has a lift?

Any suggestions on where to get a new tank?

I know tanks can be welded but this is OEM and 45 years old. Should I try and plastic weld it?

Thanks,
Marshall

nrgtrakr · 10-10-2015, 08:06 PM

How does anybody know if the tank is metal or plastic?
Our 75 has plastic dirty water tanks, I can see them. The fresh water tank is also likely plastic, but I can't see it directly without removing things, only touch.

HiJoeSilver · 10-10-2015, 08:42 PM

simply overfilling the tank shouldn't cause it to break. you may have just loosened one of the hoses which may be leaking. I'd drop the tank and check before you get to far into deciding you need a new one. Since you've been using it I'm guessing the water coming out is in decent shape so it's not unsanitary. So you may just need to fix a broken connection. But you wont know until you look.
Replacements are available, I got mine from out of doors mart, and regret it. I had to reduce the 1" insulation to 1/2" on bottom because it was taller, and it was 1 probe connection short. In hind sight I would have taken measurements left room for a little more insulation and put on fittings to my specification. Inca plastics has a large catalog of tanks as well as fittings they will put on to your specs. Vintage trailer supply has tanks as well that they will put fittings in to your specs as well.

Lumatic · 10-10-2015, 09:31 PM

In addition to overfilling I pressurized the tank. My big my stake was to tightly fit a garden hose into the fill opening. I actually could see the floor inside the trailer bulging up and when I disconnected the hose I got an explosive geyser of water. I thought the overfill hose would accommodate any overfilling but it did not.

Monza · 10-11-2015, 11:38 AM

I'd get under there remove the belly pan, take the tank out and have a look.
I could of fixed mine, but choose to replace it with new. The piece of mind not using a 45 yr water tank with unknown history made the choice easy for myself.

If the a scary task, then take it some where.

Lumatic · 10-11-2015, 12:09 PM

Quote:

Originally Posted by Monza

I'd get under there remove the belly pan, take the tank out and have a look.
I could of fixed mine, but choose to replace it with new. The piece of mind not using a 45 yr water tank with unknown history made the choice easy for myself.

If the a scary task, then take it some where.

Did you do the work yourself? I need some feedback from someone who has.

HiJoeSilver · 10-11-2015, 10:46 PM

Quote:

Originally Posted by Lumatic

Did you do the work yourself? I need some feedback from someone who has.

Fixing the tank or replacing the tank? I just finished replacing mine. It's not to difficult but there were some catches getting fittings that fit the new tank. Drain plug was different size on new tank and fill inlet was different size plus I had to change my hose size since I replaced the exterior fill 'door' that was in bad shape and doesn't seal well to begin with . My old tank had 2" of black sludge in it, yuck. Wished I had ordered one to my specs from VTS or inca plastic. Getting the fill hose over the barb fitting was a beast. I have it dropped back down for some other work for now.

Belegedhel · 10-12-2015, 09:33 AM

If your '71 is set up like my '73, then dropping the tank is not a complicated process, though there is potentially some "heavy lifting." Start by emtying the tank completely, and then disconnecting all the electrical probe connections and hose connections from the tank from the inside of the trailer. Next, roll under the trailer, and you will find a square section of bellypan that seems to be "framed" with angle iron. The side of the frame that faces the front of the trailer is bolted in place. Remove the bolts, and any rivets that may be in there as well, and you will be looking at the edge of a 1" thick piece of plywood with a sheet of aluminum under it. This piece of plywood is supporting the water tank.

Here is where the heavy lifting comes in. The sheet of plywood slides out of the angle iron frame toward the front of the trailer. You will need to have a floor jack or transmission jack with a piece of plywood on top, positioned to support the tank once you pull the sheet of plywood out of the way. Chances are your sheet of plywood will be half rotten, and swelled/rusted into place. I ended up CAREFULLY drilling a hole near the edge, attaching a heavy ratchet strap to that, and ratcheting it out, using the A-frame as an anchor. A come-along would have been a better choice.

As for repair, if you find that you have split the tank, I would say the only option is a replacement. I have toyed extensively with plastic welding, and have come to the conclusion that it really has its limits. Now if you just have a hole, then you could get a patch spun on, and that may work just fine. If you have cracks around an existing fitting, then you might be able to get a new fitting spun on--it just depends on the size/extents of the cracks.

good luck!

jbxx · 10-12-2015, 04:59 PM

I have devised a little gadget that helps me from over pressurization when filling water things. It's really simple and has saved my butt a couple times already. It's basically juat a non-cemented pvc joint. You can put them anywhere in the line but I like to do it right next to the outputs.
They seem to pop around 75# for a 3/4 fitting.
J.B.

Inland RV Center, In · 10-12-2015, 05:53 PM

Airstream has never used metal tanks, except for fresh water. The last time a metal water tank was used, I think was in the 1963 models.

Replacement fresh water tanks are available for 64 to 76 trailers, from different dealers.

Welding cracks in old water tanks, does has it's issues. Most always, a welded patch fails in a short while of useage. Perhaps old plastics back then are different from today.

Andy

Lumatic · 10-14-2015, 05:08 AM

I've got a lot of questions:
Is the plywood 1 inch as stated in a previous post. I have not seen 1 inch locally. Can it be ordered somewhere? How about 3/4 or 2 layers of 1/2 inch. Marine plywood? Any other alternatives? Should I replace the aluminum? Would galvanized be OK? How much will a new tank cost me?

Inland RV Center, In · 10-14-2015, 06:23 AM

Quote:

Originally Posted by Lumatic

I've got a lot of questions:
Is the plywood 1 inch as stated in a previous post. I have not seen 1 inch locally. Can it be ordered somewhere? How about 3/4 or 2 layers of 1/2 inch. Marine plywood? Any other alternatives? Should I replace the aluminum? Would galvanized be OK? How much will a new tank cost me?

Yes, the plywood is 1 inch thick. You can use two 1/2 inch sheets but glue them together to maximize the strength.

A water tank for your trailer costs less than $ 400.00.

Andy

Lumatic · 10-14-2015, 09:47 AM

I found the fittings between the tank inlet and trailer inlet were leaking. Fixed that and also sprayed the area with Leak Stop. Still leaking. I think I will try one last ditch effort and take a hole saw to cut an access hole from the belly and spray some more Leak Stop. Probably won't work but I might as well try.

So when facing the inevitable should I use marine plywood or just exterior? Marine plywood tends to warp. I know streamers have used synthetic material to replace floors, but forget its name. What about that.

Should I replace the aluminum under the plywood. Can I use galvanized? Is the space between the plywood and the metal bottom sheet a moisture trap and a set up for later rot? Can I skip the metal and seal and paint the bottom of the plywood?

An inquiring mind wants to know!

Belegedhel · 10-14-2015, 10:43 AM

I was able to find 1" plywood at a specialty hardwood store locally. This is the kind of place that sells plywoods with all kinds of exotic veneers, and rough cut exotic hardwoods. Anyway, had I not found the 1", I would have just sandwiched two 1/2" sheets with a bunch of Liquid Nails and called it good.

I don't think there is much benefit in using marine grade ply for this. I don't believe I did when I replaced mine. I definitely painted my wood with a good three layers of poly on sides and edges to help preserve it. I believe the aluminum sheet on the bottom side is mostly for aesthetics--just to make it look like the rest of the bellypan. You could use galvanized, or buy a sheet of aluminum, or just leave it off. Yes, I could see it trapping moisture against the wood. I think the rot in my wood was all along the edges, where they absorb water like a sponge if not sealed.

good luck!

Lumatic · 10-16-2015, 12:40 PM

Poking around I found a likely spot for the leak, under the tank intake flange. I first tried spraying the area with Home Depot Leak Stop. Didn't work. I then cut a window in the belly pan which supports the tank. I was then able to see a 4" crack extending in both directions of the intake flange. I used some JB Weld Water Weld which claims to stick to "almost anything". We'll see.

While underneath I nicked the copper propane line. Decided it was a good time to put in a T and install a Humphrey propane light while I was at it.

Belegedhel · 10-16-2015, 02:50 PM

JB Weld has a talent for self promotion. If it sticks to that polyethylene tank, I'll eat my blue beret.

kparker1022 · 09-03-2021, 01:37 PM

My data plate reads my Ambassador was manufactured 3/77, my title shows trailer is a 1978. What year tank do I get to replace the current one, leaks. Inland has this one but can't get anyone to respond back to my email and auto record says to send email on all enquires.

https://inlandrv.com/product/airstre...-tank-1970-77/. Probably a dumb question and I've got this one in my cart but wanted to confirm before spending on the tank and shipping! Thanks for any help. Also the Tank SKU: 14514 MFG: 0168. I tried searching for parts that would fit my VIN but not able to match this. Any help much appreciated!

Mx468 · 09-03-2021, 02:42 PM

Hi kparker this post is 6 years old

Belegedhel · 09-03-2021, 05:39 PM

Try calling Outofdoorsmart.com. I have always had excellent service from them, and they likely have just what you need.

good luck!

Squid · 09-03-2021, 07:03 PM

I have a 50 gallon freshwater tank you can have if you want... thought I needed to replace mine but it was just the fittings that were leaking... I gave $50 for it from some one here in Austin who was refurbishing their 27’ Overlander which is what I have