Black Water Tank Removal ?

[Lee & Joan]

My 1986 Sunraider Rear Dine / Front Bath seems to have a leak toward the front outside of the tank when it is (maybe) 1/2 or 1/3  full. I have been reading here about the ABS glue + ABS fittings ground up into plastic shavings "paste" that can be applied over the leaking area, but what happens if the leaking area can not be seen or gotten to from under the rig? Do these tanks "drop out" when the metal straps are loosened? Is there a slip fitting or are they ABS glued into the plumbing in the bathroom?

[linda s]

A friend had to get his black tank out of his Sunrader too. Asked here and on a couple of other sites and didn't get much info. He finally winged it with some help from Jon Frasier and got it out. Long but tells you a lot of crap that gets in your way. He has 2 Sunraders. A shorty and a 21 footer. Hope this helps. I've done the ABS shaved stuff with ABS glue a couple of times. On a large hole I added a layer of open weave fiberglass mat to reinforce it. Process works great. Taking the tank out sounds like a bear though

Linda S

 

I had been talking To Jon Fraiser about doing the floor and he had also had a black tank out of a shorty. A Nissan, but still a shorty.   Jon told me that in his experience the toilet flange had to come off and the 3” downspout from there should slip into a grommet on the top of the tank. He warned me that some people use silicone to seal that connection (even though it shouldn’t be needed), and that he had even seen some that were glued in. I may have had to do some cutting from inside the pipe.

 

It wasn’t too hard for me to get the flange itself loose, as once I broke the silicone seal below the toilet, the flange loosened from the (threaded) downspout without a lot of trouble. The problem from there was that with the flange removed, and the top of the downspout below the surface of the fiberglass floor under the toilet, it was impossible to hold on to, let alone turn or pull out.

 

So I put the flange back on and tried turning it clockwise. It didn’t want to do much, but it did move. Seemed like a silicone bond to me as nothing was cracking and or slipping like you might expect from a glued joint if you could get that to move at all.

 

So with this in mind I made a little spanner wrench out of some hardwood and a couple of ⅜” bolts and pulled with all my might trying to get that silicone to break free. I got it around maybe 1 turn before it wasn’t going anywhere and I needed to take a break.

 

I went back to it later and was lucky to be able to get the flange back off this time after I had tightened it on so hard. It looked like the downspout was going to have to stay in the tank. It could go straight down after all. If necessary I could cut it off.  Turns out that it was threaded at both ends and all I did with all my work was tighten it a turn. Had I been stronger, I may have damaged something there..So my advice here is leave it in the tank, especially if you have a place to jack the truck up while doing the job. I have to work in the street so I try not to do that much for the sake of the neighbors.

 

So from below there is another set of problems. On mine, and probably every Shorty, the trap from the shower is in the way of the vent pipe so that had to be loosened at one connection and disconnected at the other. I was lucky in that I was able to turn both of those old fittings by hand. The next thing to deal with are the steel straps holding the tank up.

 

As with all of the bolts going through the floor, those that hold the floor to the truck frame and those holding the grey and black tank straps, are carriage bolts. If they haven’t been replaced they are very rusty after 30 years. On my floor I replaced them with new stainless bolts as a matter of course. The bolts on my grey tank straps were very rusted, (one was in two pieces), and I had to pull the tank to replace them all.

 

The problem with the black tank strap bolts is that they are under the bathroom floor, so messing with them will be opening a can of worms or two. The nut on the bottom side is bound to be rusted to the bolt, and I had no confidence whatsoever that I could get those nuts off without turning the bolts in the floor. The wood looks pretty good down there from what I could see of it, but still, they were going to turn up there, and even if one of them pulled down through that ⅜” plywood floor I would be in for big trouble. I decided to cut the straps and pop rivet back on another piece of similar material bent at 90 degrees with a hole in each so that I could bolt them back together when I put the tank back up.

 

Now the tank was hanging there, the straps cut, the slip joint for the vent, and the downspout not quite out of the floor, the shower trap had cleared. I had to jack up the truck for awhile. It took some pushing and pulling to convince the tank to let loose of the truck, but when it did I was surprised that even then it didn’t want to come out. To quote Jon, “mine just fell right out”.  Not mine.  It was caught in the front corner of the shell and just didn’t want to clear. The other side of the tank right up against the frame. It had to go back to clear that corner, but neither myself nor my neighbor friend were able to make it go back far enough. After awhile I got the bright idea of putting a screw jack in there, between the tank and the back if the cab. I used the one that came with my ‘83, 21 footer that looks like a bottle jack and it moved back pretty easily. From there I just got back inside and kicked my heel down on the top of that downspout and mine “just fell out” too.

 

That may have been a little long winded for most of you, but you can always look it up again if you ever have to do the job. I hope it helps someone.

 

Doug  

 

[Lee & Joan]

"Tanks" Linda !!. Its been raining so much up here on the Oregon coast I have not found a good time to get under there but I am trying to get my ducks (really I have some wild ones) in order before I jump into this fun project. I am wondering if the sink, shower drain, & toilet all go into the same pipe or does each have its own pipe into the tank?

[linda s]

Different pipes for the toilet for sure. Poop pipes are always larger. The sink I think is too far to be connected to the shower but don't know. I'm not that far so you know we are getting the same rain. So what is blocking your view of the tank in the front. The cab? Wondering if some little hands could get in there and feel for a crack. There should be a model number on your tank. maybe in the back near the outflow. Be nice to see if I can look it up and find out what the tank looks like. 21 footer has a different tank than my 18 footer

Linda S