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lucymcdog · 10-18-2010, 01:24 PM

I am ordering a black water holding tank and need to know what size hole and what kind of fittings are needed for both the toilet flange and the hole under the tank that the dump valve connects to. The holding tank will be sitting on top of the floor and will have a 3/4" plywood box covering it that the toilet will sit on. Do I need some kind of extender on the flange that will allow for the 3/4" box and the 1/8" floor tile that will be over the tank? Also, the box will not sit directly on top of the tank but will be probably 1/2" above it.

Lindy

scottwtalley · 10-18-2010, 08:14 PM

Hi Lindy,
I just recently went through this for a 69 Caravel.
For the hole sizes, that will become self evident when you get the tank fittings. I got a series of hole saws after the tank and the fittings arrived.
The tricky part for me was the toilet flange.
The space between the toilet flange and the top of the tank was too big for a male threaded flange but only slightly so. I got a female threaded flange and cut a threaded connector to the correct height to fit between the flange and the tank. Maybe it was just me, but I had a very tough time getting the cut end to thread into the fitting. It finally worked, but it sure wasn't easy.
Scott

lucymcdog · 10-18-2010, 09:42 PM

thanks Scott - so am I to understand that you cut the holes in your tank yourself and then put in the fittings? I thought this information would be easy to find but I truly can't figure out how it will all work - especially the discharge hole. What kind of fitting do you use from the tank to the part where the discharge valve (the thing with the handle you pull to empty the tank) is attached? I'm wondering if a composting toilet wouldn't be a lot easier...

68 TWind · 10-19-2010, 05:45 AM

If your new tank if fiberglass you will have to cut the hole for the new fitting and glass it in. No big deal. I do recommend that you install the new tank up under the trailer and then mark the top of the new black tank through the hole in the floor where the flange goes. You need to get it right because there many not be much wiggle room and it can be difficult to get the flange location exact buy just measuring off the old tank.

Threaded PVC pipe connectors (nipples) have a taper. You can't screw them in very far before it gets tight. I had a similar situation fitting the new flange on the tank to the flange in the floor. I had to grind the taper off of a piece of PVC on my sanding table and then recut the threads with my dremel tool and a cutter. Took a while but I could not find a non tapered connector anywhere and the one I made worked great.

scottwtalley · 10-19-2010, 02:12 PM

My tank was fiberglass and I agree with Bruce and Rachel that putting on the new fittings is no big deal. I ordered it and the dump valve from Inland RV. They supplied the exhaust fittings as well as the the toilet flange fitting. They also sent an info sheet on connecting the fittings and helped me over the phone with a couple of questions I had. Taking my time, making sure the holes were placed correctly, and a quick lesson in learning to use fiberglass is what it took for me and everything came out perfectly.

I'm happy to hear that the PVC pipe connectors are tapered because that makes the difficulty I had connecting them make much more sense.

As for the composting toilet, I think your Airstream is certainly worthy of having a proper toilet. It might be a bit of a challenge but it's certainly worth it.

lucymcdog · 10-20-2010, 01:21 PM

Quote:

Originally Posted by scottwtalley

My tank was fiberglass and I agree with Bruce and Rachel that putting on the new fittings is no big deal. I ordered it and the dump valve from Inland RV. They supplied the exhaust fittings as well as the the toilet flange fitting. They also sent an info sheet on connecting the fittings and helped me over the phone with a couple of questions I had. Taking my time, making sure the holes were placed correctly, and a quick lesson in learning to use fiberglass is what it took for me and everything came out perfectly.

I'm happy to hear that the PVC pipe connectors are tapered because that makes the difficulty I had connecting them make much more sense.

As for the composting toilet, I think your Airstream is certainly worthy of having a proper toilet. It might be a bit of a challenge but it's certainly worth it.

Boy, does that sound intimidating. I am comfortable with doing electricity but plumbing is scary. Now, I have some questions: 1. Did your tank come with the holes already cut and all the fittings already installed? 2. Is your tank a curved one to fit in the corner or did you use a rectangular one and fit it as close in the corner as possible? 3. Is your tank sitting on top of the floor as opposed to under the floor? 4. Do you use just standard PVC connectors like you'd use in a real house? 5. Does the dump valve (the black thing with the handle) just fit right on the PVC?

I think the tanks I was going to order are made of polyethylene resin. Should I go with a fiberglass one instead? I am ordering 3 tanks - fresh, gray and black. I was going to order from Tank Depot but if that isn't the right kind of tank (Ronco 23 Gallon Marine Water Tank (RW-B450)) to get then I'll keep looking. Inland has a curved on-the-floor black tank but I think it is too big for my space. Andy said it was something like 27" x 27" x 61/2" and the space I have is just about 19 or 20" from the side of the trailer to the little bathroom wall. Maybe I could extend the tank out into cabinet space... My little bathroom is tiny - no shower, no sink, only a potty. A porta-potty would be easiest and cheapest but... YUCK!

Tank Depot will put in whatever holes and fittings I need. I'm ok figuring out the gray and fresh tank fittings but when it comes to the black tank, I stay up at night worrying about it.

The reason I was considering a composting toilet is because another 'streamer has one in her trailer and loves it. But it is pricey - $850 + shipping. That's awfully expensive poo.

Thanks for any more help you can give.

Lindy

scottwtalley · 10-21-2010, 08:21 PM

I just measured my black water tank & it's about 7 1/2" tall by 13' wide by something in the neighborhood of 32" to the long point. This is a fiberglass copy of the original tank that came in my 18' 1969 Caravel. it has a curved corner to fit the back street-side corner of the trailer. Although the bathroom is narrower than the 32" tank, the tank extends into the trunk area.
If this is the same corner of your bathroom then you might want to ask Andy at Inland if this tank would work for you. I wasn't able to get any other standard tank to fit.
As for having someone put in the fittings for you, it seems like it would be difficult for them to get the right locations without being able to see the trailer. I was pretty hesitant to put the fittings in mine, but it wasn't too bad. Maybe you could find a fellow Airstreamer in your area to help out.
Also - you might want to find out what was originally in your trailer and see if anyone has a replacement.