Modified black water tank

[Marlboro Mafia]

Just bought a '61 Safari.

Anyone ever install an above floor black water tank that would replace the small one under the toilet and the run under the vanity and into the closet on the other side? Would this work?

I have a twin model so there is a huge metal water tank in the driver's side under the bed. Could I add a gray water tank under the other side bed and somehow pump the shower water into this tank? Nothing large, just enough for a couple of days camping.

Thanks for your advice!

[Chuck]

What you describe is exactly how the black tank is set up in the early 70's safari's. The toilet is against the back wall of the trailer, with the vanity next to it. they both sit on top of the black tank. then in one rear corner is the shower; in the other, the closet. you can see down in the closet where the black tank sticks in there a little bit. According to the owner's manual, my trailer's black tank is 13 gallons, which seems to be enough for us for a weekend.

I know a guy that configured a trailer to use a bilge pump to transfer water between different tanks...can't remember exactly why he had to do it this way, but he is a boat builder, so this sort of thing is right up his alley.

If you search the forum, you'll find lots of threads on retrofitting grey tanks. I'd like to do it at some point in the near future, myself. Personally, I think it would be easier to just install one in between the frame rails, and let gravity do the work. there's room.

[Marlboro Mafia]

I would rather do it between the frame rails but worry about dropping the belly pan. Can you drop just the portion under the bathroom? Or, woudl you have to cut the pan to allow that?

[uwe]

I agree with Chuck. There is plenty room between th eframe rails for a sizeable grey tank. I would suggest it to be fittet as close to the axles as possible. Mine was retro fitted and holds 30gal, I believe.

[Marlboro Mafia]

How much trouble is it to drop the pan?

[Chuck]

I haven't done it myself, yet. looks to me like its really easy to drop it (just drilling out a bunch of rivets); but really HARD to put it back

[uwe]

The pan comes off easily.
Get some goggles, though.
Drill out the rivets holding the panel on, and eventually it will fall on your face.
There might be leveling jacks, or gas lines in the way, just take a good look forst, and make a plan. Generally, it is no trouble at all.
I drop the front of the trailer down low, so as to gain more clearance in the rear. There might be debris inside the belly panel, which may or may not fall on your person, depending on how the panel comes off.....
You will need a drill, and the proper sized drill bit to remove the rivets.
Do a search for belly pan and rivets, or drill bit etc. it will tell you what you need.
i use a handful of sheet metal screws to put it back, and leave them loose enought to be able to slighty maneuver the panel. (s)
Then I install the rivets from the inside to the outside, eventually replacing the sheet metal screws with rivets. i found this to be very easy.

[Moonshot]

Some black tanks are readily available and some have to be custom built.

Mine has been "on order" since December. It is a custom job. I still don't know when to expect it.

So, if you are planning to do this make sure a black tank is available before you start or you may ruin your summer.

[uwe]

The black tank in my trailer is original, and it woul d definitely be a special order, as it is curved to fit in the rear streetside corner.
My grey tank is a flat one, with a drain pointing to the rear and the inlet being on the streetside, to match the existing drain coming from the kitchen.
This aftermarket grey tank is of great quality, and fits snugly between the frame rails right behind the rear axle. It is not covered by the belly pan.

[Marlboro Mafia]

Somewhere on the forum I saw a link for a tank manufacturer. Do they have tanks that will fit?

Could I install one large tank for both gray and black water(with backflow prevention on the grey water drains coming to it?

If I do a custom tank, what material would it be? Aluminum fabricated?

[uwe]

Mafia,
My tanks are of a semi flexible plastic compound. Not sure what it is called. Polysomethingorother, probably.
check the tanks at https://www.rvpartsoutlet.com/newsto...DD554720DDDC68

This gives you an idea of what's available, at what price. Mounting is not difficult, but needs to be well thought out. I think that two tanks between frame rails and cross members, interconnected by a sizeable pipe, could be used for both black and grey.
There are opinions on this, on other threads. I personally do not see a problem with it.
Make sure you get 4o - to 5o total gallons capacity, if you're going combined.

[Marlboro Mafia]

Originally posted by uwe
The black tank in my trailer is original, and it woul d definitely be a special order, as it is curved to fit in the rear streetside corner.
My grey tank is a flat one, with a drain pointing to the rear and the inlet being on the streetside, to match the existing drain coming from the kitchen.
This aftermarket grey tank is of great quality, and fits snugly between the frame rails right behind the rear axle. It is not covered by the belly pan.

Not covered by belly pan? What about road debris, etc? Any problems? Man I hate to drop that pan.

Would a 20 to 30 gallon flat tank under the bathroom at the rear disturb towing alot? What is the weight(gallon = 8 pounds?)?

There is a huge metal fresh water tank under one of the twin beds. Must be 6' long x 2' round. Is that original?

[overlander64]

Greetings Marlboro Mafia

I have a twin model so there is a huge metal water tank in the driver's side under the bed.

Yes, this is likely the original pressurized water tank and it is usually constructed of galvanized steel. There have been several owners of early '60s models recently who have found the bottom of these tanks have developed numerous tiny pin holes resulting in leaks that could quickly rot the floor below. There isn't an economical replacement for the pressurized tanks out there so many have resorted to using a modern plastic tank and converting to a demand system with electric demand pump.

Could I add a gray water tank under the other side bed and somehow pump the shower water into this tank?

It is something that could be done, but whether it would be feasible or advisable is another question. All of the waste wash water would need to be pumped up to the tank - - then another pump would likely be needed to pump the tank out at the dump station as the typical drains used for the inside storage tanks would gravity drain far too slowly for the demand of fairly quick in-and-out at busy dump stations.

If my Overlander had the above floor blackwater tank, I know that I would be looking at having a graywater tank mounted between the frame rails below the bathroom - - as it stands the only method with my coach is much more involved (either increasing the size of the current blackwater tank and using it for both gray and blackwater or significant plumbing modifications). While the weight of the empty tank shouldn't be a great issue, it would be ill-advised to tow any significant distance with fluid in the tank as it would nearly directly subtract weight from the hitch on a single axle trailer - - not to mention the reduction in the available weight carrying capacity for possessions in the coach.

Good luck with your project!

Kevin

[uwe]

Never had a problem so far with debris. I guess a piece of tire or a 2x4 could rearrange my plumbing system, if I ran over it.
It is flush, though. Nothing but the drain sticks down.
A heavy tank in the very rear of the trailer is not a good idea, in my opinion.
The weight will eventually cause rear end separation.