New Member, toilet, plumbing, floor questions

[iowamike]

Hello all,
I just picked up my first Airstream: a 1975 Excella 500. My plan is to mostly gut her & rebuild. I knew I would be facing some flooring issues in the rear bath, but I was surprised to find the previous owner had patched the floor with MDF(!)

The nice part was that this patch was easily removed with a garden trowel! Now that I have dug into it, I found that the flange on the waste tank is broken:

(that is not what you think inside the tank. It's rotten MDF bits)
I would like to try to salvage the tank if possible. Can this be repaired with by plastic welding? If so, what kind of flange or opening is supposed to be there? Is it just a hole or should there be some sort of ring fitting?

I am thinking I will be installing a dometic 310, if that has any bearing on how I should proceed...

Also, I will eventually be selling/donating most of the original interior parts. I don't know what inventory I have just yet, but if anyone is looking for something in particular feel free to message me!

Thanks!

[wahoonc]

That be UGGGLLLLY!

Yes there is a flange. I don't know if you can weld one on or not.

Replacement tanks with the flange are available but they are a bit pricey. I will have to see if I can get you a picture of the flange on the tank. My tanks are out at the moment so it shouldn't be too hard. The tanks are supposed to be polyethelyne. I have done some minor repairs on mine with a heat welder using a milk jug for the extra material. Haven't put it to the test yet.

Aaron

[Panama Red]

Hey Mike! Isn't it awesome to see some of the "repair" work done by PO's? Hopefully, forty years from now, nobody ever has to tear into my work and go, "WHAT THE...?"
Anyways, there is supposed to be a female threaded flange in there, and a male threaded piece, that the toilet will fasten to, screws into that.

My gray water tank outlet was cracked, and I used a giant soldering iron and cut up an old Tupperware lid into strips for welding sticks. Make sure you get everything COMPLETELY dry. Any water in the weld will steam, causing tiny little holes that continue to leak, ever so slightly... Voice of experience there. Also, make sure you get compatible plastic for the weld. I can't remember the names of them, but there are a few different types of plastic that look similar, but don't work. I tested a couple different types before I found the Tupperware lid that was compatible.

Somewhere in my "Resurrecting Big Bertha" thread I have a picture of a really ugly plastic weld! that has held so far.

Good luck with your refurb!

-Red

[iowamike]

Once I get this fixed I don't ever want to see it again, so I am probably going to hire someone to do the weld for me.

The problem is that I believe the threads are completely destroyed. Any idea where I might find a "donor" threaded port in compatible plastic?

Thanks.

[Panama Red]

Find an RV junkyard... We have one locally, and it's a hoot to walk through.

[iowamike]

My local plastics guy says that poly tanks that old won't weld very well. So... anyone know where I can get a new tank?

Maybe I should just get an incinerator toilet?

[Protagonist]

Originally Posted by iowamike

My local plastics guy says that poly tanks that old won't weld very well. So... anyone know where I can get a new tank?

Might have better luck with ABS rather than poly.

[igorbel]

Check Silvertrailersupply.com. It looks like this guys have all kind of Airstream holding tanks.

[iowamike]

Silvertrailersupply.com has 2 different tanks for my year AS, but they are both for the center bath model (mine is rear). I think I am going to just cover it up and roll with a porta-pot for a year or so. I can come back to this project later. Too many other things to do!

[Cyquest]

INCA plastic moulding co. still make holding tanks for new and vintage airstreams. They should have what you need.

[Jammer]

Originally Posted by iowamike

My local plastics guy says that poly tanks that old won't weld very well.

I have had good results so far with flame treating the poly and then using West System epoxy. Any other high quality epoxy should also work as long as you flame treat.

I patched the holding tank on my Avion C-11 last spring. No replacements available aside from very expensive welded stainless steel ones. It's held so far. I ended up using fiberglass to reinforce it as some of the areas were cracked and the plastic had become brittle over the years.

There are many sources for replacement tank fittings. Try here:

Holding Tanks,Fittings, Vents on Sale! - Adventure RV

[RM66caravel]

I thought I had commented or at least welcomed you but I did not and I must say sorry for the oversite! Welcome and you have an awesome project there! I am just wondering what other wonderful previous owner repairs you will discover and fix!
Again welcome
Cliff