(Formally "Plan V: A Van Dwelling Blog", when I lived in a 1978 Dodge Xplorer 228 Class B motorhome van)

Wednesday, May 8, 2013

New holding tank installed!

I got the new holding tank installed! The only thing I need to keep an eye on is the mounts and the outlet pipe. Installation went pretty smoothly. I had to make several trips to Lowe's to get ABS pipe fittings and a 2ft piece of 3" ABS pipe. Plus one trip each to two different RV shops for the Valterra parts (fittings, drain valve, caps). Tank, parts and all... set me back about $325-350. Not too bad really since I saved about $250+ in labor doing it myself.

For your viewing pleasure.. lots of photos from start to finish.

I drove one side of the van up onto Lynx Levelers to raise it up high enough to get the tank under the running boards. Worked like a charm.

Fresh new tank! (upside down)

2-1/4" hole cut in the tank and grommet installed. The way I figured out how to cut the hole was I installed the tank and marked the opening area through the floor on the tank with a sharpie, then took it back off and marked it with the grommet for a perfect circle, then marked a spot in the center of the perfect circle, drilled a small hole in the dot, then used the hole saw. It worked perfectly! Then I cleaned up the cut with sandpaper and installed the grommet. It took using a heat gun lightly on the grommet (a hair dryer would have also worked) to soften it and make it pliable enough to get the last 1/5 down in the tank since it's pretty rigid rubber when it's cold.

Closer photo of the grommet. As per the instructions, I sealed around it with 100% Silicone sealant. Regular silicone caulking might also work but this stuff is a little thicker.

Tank installed (with pipe grommet and inlet pipe on top going up through the floor).

Pipe coming from the bathroom sink and going to the new rubber 90 degree elbow (Fernco PQL150) then down to the pipe going into the tank grommet. Yes, you do see PVC between the elbow and tank grommet but at that time, I didn't think I needed to buy any 1-1/2" ABS, but I did. By then, I already had the tank installed. In order to change it, I would have to drop the tank to get at the clamp on the grommet sealing the pipe. It doesn't matter since it has the rubber grommet on the tank and the rubber elbow up top. You may also notice the coupler along the ABS pipe before the rubber elbow. I cut it back too far so rather than using another rubber coupler, I put a regular cemented ABS coupler and short piece of pipe. This setup allows the tank to be removed easily in the future and is superior to the original pipe that had a short reinforced coupler between the tank inlet pipe and an ABS 90 degree elbow.

New tank drain/outlet parts partly assembled and laid out. All the ABS was already assembled, just waiting to be permanently installed at this point.

Due to the design, the combined drain pipe from the galley sink and shower drain must tie in through a tree after the tank but before the drain valve, so that's what you see here. Even with the drain valve close, the tanks will empty into the tank.. from the bottom. They are higher than the water level in the tank (unless it gets so full it overflows..) so gravity and vacuum will do it's thing and fill the tank.

All assembled and ready to go! I drilled a couple of holes and used some "plumbers tape" (metal strapping to suspend pipes and duct work) to help secure the long drain pipe (10.5 inches) so it doesn't bounce around and break something. It's not visible, but I also and put in a piece of wood between the running board and pipe end fitting so it can't move as much. It's held in place by a couple of screws that were run through the running board and then into the piece of wood.

The two drain outlets: Grey water tank on the left and recirculating toilet on the right.. with tail pipe in the middle. I may add a tail pipe extension tip to put it out a bit further so it doesn't expel the exhaust on the toilet drain pipe as badly.

Further away view of the two drain outlets.


  1. Nice Blog!! Great Post !! Like your Blog and your ideas and i think its benificial for us and i keep to visit your blog regularly because i got lot of information through you blog
    Abs pipe

  2. Great tips. very well-written, keyword-oriented and incredibly useful. its really interesting to many readers. I really appreciate this, thanks

    Plastic Pipe

  3. Hi there!

    We have the same van! And, I know at least three other van 224 dwellers on the road- one of which is '78. I was shocked to find this specific post on the grey water as I have been searching the same tank for awhile. Any hints on the model and source would be greatly appreciated. I don't skype but I would be happy to exchange emails and info - breakdancingcyclops@gmail.com

    Happy Journeys, Pete

  4. Just saw the tank source post below! Thank you!! Lets chat. Pete

  5. Just saw the tank source post below! Thank you!! Lets chat. Pete

  6. I'm glad this as well as the tank source post was helpful. I had no such source when I was doing this. I couldn't even find good photos of the tank and dump outlets on the web.

    There is one thing to be careful of: http://cubey7800.blogspot.com/2013/06/tailpipe-fix.html

  7. Hi there! My boyfriend and I just acquired one of these vans and have been putting in the time and $ to get her ready. We have also had a lot of trouble finding information about specific parts, such as the water tanks. I was wondering what information you had about the freshwater tank, not the gray water holding tank? We haven't been able to find any info about the size, shape, replacements of this tank anywhere, but do know from the previous owners that it is cracked. Looks like you found a great resource for the holding tank.. thanks so much!

    Very cool to see your blog about traveling/repairing/adventuring in this van, we can wait to do it ourselves. Cheers! cathyjsoukup@gmail.com

    1. I don't have the measurements of the tank but it's just a big rectangle. You should be able to measure the space and figure it out from there.

      I don't have a photo of the tank all in one, but here are three photos that show the ends where the connections are:

      Passenger side, filler, drain and air vent, with new hoses:

      Driver's side, outlet to the pump: http://img.photobucket.com/albums/v222/illiop/78dodge/Hpim5788.jpg

      A closer picture of the pump side; after I replaced all of the PolyB pipes with PEX and put in a new pump, filter and reinforced hose: