102D3 waste tank selection

[Bustle]

It's about that time to pick the waste tank for the 102D3 (the 40ft). I have chosen the rear most bay for the fresh water (passenger side) and waste tank (driver side). I have seen someone use a plastic barrel, but I'd like to keep it rectangular if possible for a better fit, and more volume. Black and gray will be combined. We don't boondock more than a few days at a time anyway. Any suggestions or preferred suppliers?

For the toilet I am planning on using Thetford Marine Tecma macerator, to aid with the passage of fluids from toilet in the OEM lavatory location to the rear bay.
The black/gray tank vent will probably follow the same route, and out through the bustle.

[RJ]

Bustle -

You're not removing the factory restroom? 

Do you realize that underneath the stainless steel floor you've got 20+ years of urine-soaked plywood, the smell of which you'll never get out of the bus by leaving in the OEM lav? Especially in the summertime!

Anyway, to answer your question, I would suggest you order your tanks from Ardemco - one of the advertisers in Bus Conversions Magazine. By doing so, you're helping to support a vendor that's been supporting the magazine and this forum for over 25 years now. If you can't find a pre-made size in their catalog, they'll custom make one to your specifications, plus they'll spin in any fittings you may need, too. They may not be the cheapest, but their quality is excellent - you get what you pay for.

Code is having the fresh water, shore power, and sewage drain all on the driver's side, and all relatively close together.

Where are you placing the house batteries? My coach has them (four marine deep-cycle 8Ds) on the passenger side, rear bay, with the 150g fresh, 90g grey and 60g black tanks on the driver's side. Straight drop from electric Microphor toilet into black tank - no pipe run. Wye fitting allows grey to flush black, if necessary. Tanks vent straight to roof (with a mushroom cap) via the rear corner of bathroom vanity & medicine cabinet. This configuration allows the major "heavy" house systems' weight to be carried by the drive and tag axles.

(Side note: Previous coach had a 100g grey/black tank. Had to use a lot of chemicals to keep the smell under control. Not so much of an issue with the separate grey/black in current coach, as grey drain is usually left open while hooked up. When closed, the grey stinks before the black! Also, don't waste your money on over-priced "rv holding tank chemicals", simply use the septic tank tablets found in any hardware store.)

FWIW & HTH. . .

[Bustle]

You're not removing the factory restroom? 

Do you realize that underneath the stainless steel floor you've got 20+ years of urine-soaked plywood, the smell of which you'll never get out of the bus by leaving in the OEM lav? Especially in the summertime!

You ain't kidding. This was probably the worst thing ever. The smell was unbearable in the 100F heat. How much more of the plywood should I remove? We are putting another layer on top of this one. Should I also replace those insulating blankets that are underneath the plywood?

[Bustle]

Anyway, to answer your question, I would suggest you order your tanks from Ardemco - one of the advertisers in Bus Conversions Magazine. By doing so, you're helping to support a vendor that's been supporting the magazine and this forum for over 25 years now.

If you can't find a pre-made size in their catalog, they'll custom make one to your specifications, plus they'll spin in any fittings you may need, too. They may not be the cheapest, but their quality is excellent - you get what you pay for.

Will do - I will give them a shout today. I saw the ad pop-up yesterday after I posted my question.

Code is having the fresh water, shore power, and sewage drain all on the driver's side, and all relatively close together.

The plan is to have all of that on the driver's side, just like a traditional RV.

Where are you placing the house batteries? My coach has them (four marine deep-cycle 8Ds) on the passenger side, rear bay, with the 150g fresh, 90g grey and 60g black tanks on the driver's side. Straight drop from electric Microphor toilet into black tank - no pipe run. Wye fitting allows grey to flush black, if necessary. Tanks vent straight to roof (with a mushroom cap) via the rear corner of bathroom vanity & medicine cabinet. This configuration allows the major "heavy" house systems' weight to be carried by the drive and tag axles.

The current plan is to have electrical (inverter chargers, panels, transformers..) and 20 kWh of LifePo4 closer to the front of the bus; front bay.

(Side note: Previous coach had a 100g grey/black tank. Had to use a lot of chemicals to keep the smell under control. Not so much of an issue with the separate grey/black in current coach, as grey drain is usually left open while hooked up. When closed, the grey stinks before the black! Also, don't waste your money on over-priced "rv holding tank chemicals", simply use the septic tank tablets found in any hardware store.)

FWIW & HTH. . .

I've only used the rv holding tank chemicals that came with our Class-A. Previous owner had a stash that we went through over the span of a few years. Most of those treatments are made out of formaldehyde and some kind of fragrance, so not the best thing anyway. For the past few years I've been using the modified version of the "Geo" method - while it does nothing to control the smell of current content, it helps move things along faster, and prevents sticking. The trick is to not hold on to the content for too long to give it time to start breaking down.

Our black tank always starts off with 5 gallons of fresh, and treated water (oxyclean+calgon+cheap detergent), which allows us to use "quality" plush household Cottonelle toilet paper. Trick here is to not dump immediately after using the bathroom. You need to give it at least 30 minutes to start disintegrating in water. You can test your toilet paper in a cup to see how fast it disintegrates after getting wet.

For the smell moving forward - I think we will get no smell coming out of the tank through the toilet, or the sinks/showers due to venting and p-traps.

Here is the toilet we were looking at using, at the same location where the existing toilet was. The plumbing will probably be routed through the interior behind a service chute that's covered by the interior. 

https://www.youtube.com/watch?v=W9pvWgslYjU

[RJ]

You ain't kidding. This was probably the worst thing ever. The smell was unbearable in the 100F heat. How much more of the plywood should I remove? We are putting another layer on top of this one. Should I also replace those insulating blankets that are underneath the plywood?

Excuse my ignorance, I wasn't aware that you were removing the factory restroom.

Thanks for the pic - the visual helps.  I would cut/remove the plywood and insulating blankets as far back as you can see staining, which may be another 8"-12" from where you already are. The wall insulation may also have some staining, another source of smell.

That rusted out metal should also be addressed in some manner before you hide it with new flooring, which I'm sure you've probably already figured out.

Please refresh my memory as to why you're putting your toilet in the same location as the factory, instead of directly over the black tank like 99.99% of conversions do? I'm trying to understand your logic here.

Without having any experience with macerator systems, the Thetford you referenced is interesting - but having p-traps concerns me, especially if the Cottonelle plugs up the impeller before it has a chance to start breaking down.. The KISS system of the straight drop is my preference, as it is for most busnuts.

Something else to consider - the wastewater drain.  As you can see in these photos, on my coach the drain is thru the floor of the baggage bay. Biggest advantage to this is that I can leave the bay door closed when not dumping.  Biggest disadvantage is that when the coach settles as the air bleeds off, there's quite a sharp bend to the flexible sewer hose, but not so severe that it hampers flow.  My MCI had to have the bay door open to attach the sewer hose, too each his own.  I like the closed bay system better for me, because I normally leave the grey tank drain valve open when parked with full hookups, thus I can leave the sewer hose attached.

I've added the clear elbow with the flush attachment in order to rinse the black tank after dumping. The white PVC elbow and hose connection gives me a way to leave this all hooked up while parked, and the duckbill gasket keeps the effluent out of the hose, somewhat, but I normally turn on the water slightly so there's flow before pulling the dump valve. I use a brass "wye" with on/off ball valves at the park's water supply - one side fresh water into the coach, the other side to the black tank rinse. I use a pressure regulator on the fresh water side, but none on the rinse side, which hasn't been an issue.

FWIW & HTH. . .

[lvmci]

I have always kept the valves closed till emptying. Then letting the black water empty first, opening the grey to back flush into the black compartment, close off the grey, letting the now cleaner black empty. close off black and empty the Grey, clearing the throat, so to speak. I then put some clear thru the toilet and add some chemicals to break down any leftovers, which get swished around on movement, havent ever had the caked cone problems with this technique, lvmci..

[Jim Blackwood]

I'll be building my tanks and drains to run a 2" valve from the gray to the opposite side of the black from the 3" drain, with a smaller bottom drain for the gray. The 3" will go through the panel behind the rear bay door, possibly with a cable pull on the valve mounted through the panel so it's accessible from outside.

This way I'll drain the black, then drain the gray through the black which should flush it. The small drain is in case the gray gets full and needs drained off some. I'll put a fitting for a green or black hose on it.

Hope to get started on welding up the tanks (plastic) this winter.

Jim

[windtrader]

Our black tank always starts off with 5 gallons of fresh, and treated water (oxyclean+calgon+cheap detergent), which allows us to use "quality" plush household Cottonelle toilet paper. Trick here is to not dump immediately after using the bathroom. You need to give it at least 30 minutes

Very interested in your special potty stew. Where did you come up with that combo?

[ktmossman]

Having just ordered my tanks, my advice is to find a pre-made tank that will work for you.  I was sure I was going to do custom tanks to fit the unique dimensions I wanted.  I pretty quickly realized that it would cost me 2-3X more than what I could buy "off the shelf" for the same volume tank.  I will have to do a little more structure around the tanks because they won't fit as tight, but the cost savings is HUGE.  I will have 200 gal of fresh and 170 gal of combined black/grey. 

I started with my most critical dimension and went from there to find tanks which would fit within where I wanted them and give me the most volume.  I had originally wanted 200/200, but I can live with 200/170 to save a serious chunk of $$$.

Don't get too stuck on "RV tanks" on the websites, especially for the fresh water.  I happened to end up going with a potable water loaf tank for fresh water and a RV tank for black.

Also, don't forget shipping...  Because of their dimensions, these things get expensive to freight.

[chessie4905]

about halfway through the travels this summer, we started waiting to dump first thing when we got to a new campground.  Assured everything was broken up. Flushed thoroughly also.

[Bustle]

That rusted out metal should also be addressed in some manner before you hide it with new flooring, which I'm sure you've probably already figured out.

All of the  rust has been cleaned up and neutralized. I don't think I'll be welding any more new metal.

Please refresh my memory as to why you're putting your toilet in the same location as the factory, instead of directly over the black tank like 99.99% of conversions do? I'm trying to understand your logic here.

In our original floor plan the RV type toilet was going to be right above the bay. Since we got a 40ft bus instead of 45ft bus as planned we had to re-do the floor plan. We have to sets of bunks, another single, and a pull out couch. Enough sleeping space for 7.

[Bustle]

Very interested in your special potty stew. Where did you come up with that combo?

It's a concoction sometimes referred to as "Geo" method, or improved Geo.  It's popular on the RV boards.. Some people swear by it.  It's mostly benign, but Calgon water softener does help prevent sticking from my empirical observation, but so does actually having more water content

[Jim Blackwood]

With the usual RV toilet, I recommend once you are parked, keep water in the bowl. How much is up to you but don't be stingy. That helps several ways. Kids dropped in the pool will keep their heads down, you get a good flush, and there is adequate fluid for liquifaction in the tank. Sometimes it isn't obvious.

Adequate venting is the next big thing. If you can encourage airflow through the tank it will help immensely.

Jim

[windtrader]

Adequate venting is the next big thing. If you can encourage airflow through the tank it will help immensely.

Jim

Yes, I jotted that down awhile back. Had not considered the biological process releases less bad odor when the tank is aerated with fresh water. One of the many projects on the list is to add a computer pancake fan to ventilate the black box and it can also pull air through the potty hole and prevent any smell from entering the coach. Seems like a double win

[chessie4905]

make sure the roof vent isn't  adjacent to a ceiling fan exhaust.