Expanded Grey Water Capacity

[musicmaster]

Has anyone installed a second grey tank and tied it in to the OEM grey
tank to expand capacity? This seems like it would be simpler than trying to replace the OEM tank even when building a new frame. This would only require tying in a vent for the new tank and adding a fitting to the old tank, for the new one to drain into it. By the way, the trailer I'm working on is an 76 sovereign, and the grey tank is small. My 10 year old daughter
filled it up washing grapes one day.

[ventport]

Those must have been very large grapes!

[musicmaster]

They were average size, but there were a bunch of them. Ha Ha

[87MH]

Originally Posted by musicmaster

Has anyone installed a second grey tank and tied it in to the OEM grey...My 10 year old daughter filled it up washing grapes.

Great idea on expanding the utility of the '76 by adding an additional tank....the "limiting camping factor" on our '78 is the gray water. Don't forget to vent both of the tanks in addition to the common drain- just route the air vent connections together to a common air vent to the roof.

Saw in another thread where you were increasing your frame clearance height by dropping your axle mounting flange by 1 1/2" - I've been giving a lot of thought to my axle replacement lately - I raised my ground to frame distance by around 3"...the 3" is about right for my requirements, but, if I had to do it over, I would go with a 10 to 20 degree down start angle and incorporate a 3" drop in the axle mount flange while rebuilding the frame. My hindsight thoughts only.

While into the new frame, I would build it hell for stout - weight be dammed - the Airstream will outlive several tow vehicles - so by a weight and tow rated Tow Vehicle when the time comes. I also believe I would either expand the potable water tank, or add a second potable water tank as you are adding the second gray water.

Oh, tires - leave enough room to replace the problem riddled 15" ST's with 16" LT tires - better life - better ride - much better tire selection.

One more woulda-shoulda-coulda from my hindsight reflections - build some sort of pressure wash into the black and gray water tanks. Adding a clean out fitting (fresh water wash) would be easy while you have the frame exposed - not so easy when everything is buttoned up.

Post pics - I bet you will get more hints from those who have "been there and done that" on how to improve your Airstreams utillity with a minimum of investment while rebuilding the frame. Several individuals have built new frames here on the Forums recently - several hours spent now studying what they did right (and asking them what they would do differently if they had a chance to do it over) may save you many days of grief during the actual frame construction and shell remating.

Good luck - and where are the pics?

[wasagachris]

Musicmaster I have been reading your posts. If I am correct your trailer is now a rear bath with the grey and black tanks located at the rear of the unit.
You wish to convert it to a center bath so by using the tank setup for a center bath and keeping the tanks from the rear bath you could tie the two pairs of tanks together to create two pairs of tanks, one pair for black water and two pairs of tanks for grey water.
The tanks for the center bath could be plumbed to drain into the tanks for the rear bath and you would keep the original drain location of the rear bath for connection to a sewer hose.
You would have to add a drain valve to the black tank at least in order to fill it first. Once it was full open that valve and drain it into the second black tank. The center bath tanks are larger than the rear bath tanks so you would have to be careful not to overfill the second rear bath black tank.
Here is a picture of my tank set up. The tank on the left is the grey tank and the one on the right is the black tank. They both sit in galvanized boxes. They are located just behind the axles.
The only concern I would have is the extra weight sitting behind the axles. You would have to really beef up the frame to stand the weight. Having this much weight that far back would also change the tongue weight of the trailer and it's handling characteristics.
I have a 75 rear bath trailer as well and have noticed how small the tanks are. Maybe the center bath tank sizes which are larger would be sufficient for your needs.

[wasagachris]

Heres the pics of the tank setup I forgot to post

[Wingeezer]

I have been surprised how quickly we fill up our grey water tank when camping without sewer connections. Even trying to really conserve water when showering and washing dishes, I think the two of us would be lucky to get three days use before its starts backing up into the shower. I believe our grey tank is supposed to be about 39 US gal.

Be interested to know if other folks manage any better than we do.


On the other hand, we could go for weeks with the black tank - maybe because of a house rule I set when we first started RV-ing that we only "pee" in it as I didn't want to
have change my profession from mechanical engineer to sanitation engineer!

Because the black tank lasts so well, I often thought it would be great if I could use a simple transfer pump to move grey water into the black tank to make better use of the two. I don't imagine there is a simple way to arrange this though without removing the underbellly panels to get at things.

Unfortunately. I can't really undertake projects like this where we live at present.

Maybe there is a simpler way? I suppose I could just invest on a blue boy.


Brian .

[87MH]

Originally Posted by Wingeezer

I have been surprised how quickly we fill up our grey water tank when camping without sewer connections. Even trying to really conserve water when showering and washing dishes, I think the two of us would be lucky to get three days use before its starts backing up into the shower. I believe our grey tank is supposed to be about 39 US gal...
Be interested to know if other folks manage any better than we do...

For our '78 Sovereign (31') center bath, the stated capacities are 23 gallons main (Black), and 13 gallons aux (Gray).

Just for grins, I measured (in a one gallon container and a five gallon bucket) exactly how much fluid each tank took....exhibiting just a bit of OC anality here...

The main (black) tank took 30 gallons and the water level was lacking about 1/4" from being at the bottom of the toilet extension pipe, the shower pan quit taking fluid (gray tank) at 23 gallons.

I would not want to actually tow the trailer with this much fluid in the tanks, as either tank would surely slosh over onto the floor.

At the lake at TAHI I normally let the gray water tank fill up prior to draining - I usually empty the black tank at the same time, and a goodly amount of head helps to flush the "black" in the BW tank out of the drain hose. On several occasions I have allowed (by accident) the gray water to back up into the shower pan - pretty nasty. I highly recommend a power wash in the gray water tank if at all convenient to install.

Like Wingeezer, it's a stretch for us to do a Friday, Saturday, Sunday camping trip without approaching the limits of the gray water tank.

[blickcd]

Both my grey and black tanks are 25 gallons. For my sweetie and I we can get by with this, but I have a few tricks I'll pass on.

I found two dish pans that fit perfectly into the galley sink, acting as liners. I'll wash dishes in these pans and then dump them down the toilet.

For longer stays, if the campground has dishwater dump stations, I'll dump the pans into a bucket and dump the water there. I also have a blue tote tank that gets use when staying more than 3 days with no sewer hookup. Note that we always use the shower in our trailer, but if we really had to conserve grey water tank space we could use the public facilities.

Regarding the size of the factory tanks I think a better split would have been 30 grey and 20 black. However, they sit in between the frame rails and are further boxed in by crossmembers, so the only way to increase volume is to make them deeper.

I've upgraded my axles to the ones that give higher ground clearance. Should I need to remove either holding tank for some reason, I'll look at what larger sized replacements might be available. Of course that would mean fabricating a new enclosure pan and reworking the dump valves so no simple task. The increased weight is of some concern, but my grey tank is just behind the rear axle. For a short drive to the dump station when leaving camp, that would probably be okay.

Christopher

[withidl]

Originally Posted by Wingeezer

Because the black tank lasts so well, I often thought it would be great if I could use a simple transfer pump to move grey water into the black tank to make better use of the two. I don't imagine there is a simple way to arrange this though without removing the underbellly panels to get at things.

Unfortunately. I can't really undertake projects like this where we live at present.

Maybe there is a simpler way? I suppose I could just invest on a blue boy.


Brian .

Wingeezer, I've got your "simpler way" which I have used many times with my 2002 31' ASCL which has a 39 gallon black tank and a 37 gallon grey tank which SHARE the dump MANIFOLD. The following proceedure will allow you to move grey water to the black tank:

• When the grey tank is totally full, leave the manifold cap in place, open the grey slide valve and allow the manifold to fill with grey water.
• Then, leaving the grey valve open, open the black slide valve. This will cause the grey water to "seek a level" with the black tank water.
• When you "estimate" that the tanks have almost leveled with one another, close the black slide valve first and then close the grey valve.
• Because grey water was still flowing into the black tank when the black valve was closed the manifold is left holding only a small amount of grey water which is essentially soapy shower/dish water.
• When at the dump station, removing the manifold cap to attach the dump hose will allow that small amount of grey water to spill (you could catch it with a large bowl if necessary) as it's not really "environmentally offensive" so it ain't no big deal.

As stated above, I've used this proceedure many times. It allows you to gain almost half again more grey storage AND dilutes the black water for more ease of dumping. NOTE: If using this proceedure, make a note someplace that the manifold is full or you will surprise yourself when you remove the manifold cap!

[Wingeezer]

Originally Posted by blickcd

Both my grey and black tanks are 25 gallons. For my sweetie and I we can get by with this, but I have a few tricks I'll pass on.

I found two dish pans that fit perfectly into the galley sink, acting as liners. I'll wash dishes in these pans and then dump them down the toilet.

For longer stays, if the campground has dishwater dump stations, I'll dump the pans into a bucket and dump the water there. I also have a blue tote tank that gets use when staying more than 3 days with no sewer hookup. Note that we always use the shower in our trailer, but if we really had to conserve grey water tank space we could use the public facilities.

Regarding the size of the factory tanks I think a better split would have been 30 grey and 20 black. However, they sit in between the frame rails and are further boxed in by crossmembers, so the only way to increase volume is to make them deeper.

I've upgraded my axles to the ones that give higher ground clearance. Should I need to remove either holding tank for some reason, I'll look at what larger sized replacements might be available. Of course that would mean fabricating a new enclosure pan and reworking the dump valves so no simple task. The increased weight is of some concern, but my grey tank is just behind the rear axle. For a short drive to the dump station when leaving camp, that would probably be okay.

Christopher

I spoke with a MH owner when in Florida last year who showed me a novel solution that he had to grey water disposal.

He had piped a small (maybe 1/2" valve and drain line from the waste outlet pipe back under the middle of his motor home somewhere near the back axle.

When he needed to, he would open the grey water dump - I guess the sewer cap stopped it from leaking - and then cracked open his 1/2 valve slightly allowing the grey water to slowly dissipate unseen under his MH!

Not a very socially acceptable way of doing things I guess, but he was quite proud of his solution!


Brian.

[xrvr]

Need to look into the legality of this . Fines can be a lot in some states. But I bet it works . jim

[musicmaster]

Here is a pic of the original tanks in the old frame. I plan to install a new aux. grey tank in the bay behind axles and plumb it into the existing grey tank. I don't have any plans to expand the black tank. BTW the left is black and the right is the grey. I've even thought of tying the new tank into the back of the black tank , and add a cutoff between them. Then I could use it to flush through the black tank.

[Wingeezer]

That sounds like an excellent idea! The only thing that worries me slightly is that I thought you would wind up with a fairly large volume of grey water trapped in the outlet that would then gush out when you removed the cap. From what you say, it sounds as though it isn't a big problem to deal with.

Thanks for the tip! ............... Brian.

[musicmaster]

Has anyone added or know how to add inlets to existing holding tanks?I talked to Pelland tanks and they sell a tool for spin welding fittings onto polyethelene tanks, but it is very expensive $209.00. Any suggestions?

[tabney0315]

Originally Posted by musicmaster

Has anyone added or know how to add inlets to existing holding tanks?I talked to Pelland tanks and they sell a tool for spin welding fittings onto polyethelene tanks, but it is very expensive $209.00. Any suggestions?

Bump. Anyone know the answer to the above?