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Topic: Sealand/Dometic 511 toilet question (Read 612 times) previous topic - next topic

Sealand/Dometic 511 toilet question

Tried to find out why there is a drain plug on the back side of our 511 toilet. No mention anywhere that I could find.
It is parallel to the floor and can drain "liquid" from the vertical hole and two square openings on the back of the base.
Weird, because it only traps leakage from the two neoprene seals above it, but no way to let the "liquid" drain out without removing the plug.
Why didn't the designer just provide a drain hole into the regular large drain?
Without knowing that this area is there in the back of the base, the "liquid" could freeze (up here in Wisconsin) and damage the base and ball seal.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Sealand/Dometic 511 toilet question

Reply #1 –
Quote from: nitehawk –
Tried to find out why there is a drain plug on the back side of our 511 toilet. No mention anywhere that I could find.
It is parallel to the floor and can drain "liquid" from the vertical hole and two square openings on the back of the base.
Weird, because it only traps leakage from the two neoprene seals above it, but no way to let the "liquid" drain out without removing the plug.
Why didn't the designer just provide a drain hole into the regular large drain?
Without knowing that this area is there in the back of the base, the "liquid" could freeze (up here in Wisconsin) and damage the base and ball seal.

As I remember, there are two types of seals for the Sealand toilets depending on the model/year;  One has a drain hole and the other without.  I'm wondering if yours isn't the one without the drain hole and that's the separate drain is needed for that type seal.


Joe Phebus and Jaime Trujillo
2002 U270 3410  Build: 5953 Motorcader # 18595
2100 W Solar, 600 AH Battleborn Batteries,  Victron Multi-Plus II 3000 Inverter, Cerbo GX, & MPPT Chargers
1992 Geo Tracker

Re: Sealand/Dometic 511 toilet question

Reply #2 –
So what do I do? Drill a hole to let the blind hole drain into the black tank? Wouldn't this let odor get up inside?
Currently there are about six holes around on the front side of the base that must be draining the seepage under the thick seal and the ball seal.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Sealand/Dometic 511 toilet question

Reply #3 –
The popular Sealand 511 Toilet has gone through design modifications with major changes about 10 years ago:

Nitehawk has run into some before & after conflicts.

Earlier design had two water overflow drain holes cast in the rear of the porcelain bowl where each has a pathway that exits out the bottom of the porcelain bowl in two separate places.

Earlier black plastic base has drain holes in alignment with the bottom porcelain exit holes. The base holes flow water around the white ball valve that closes off the toilet so any overflow will drain directly in the holding tank even if valve is closed. The plastic base drain holes have water traps to prevent holding tank smells.

The earlier big rubber bowl/base gasket set has two small holes aligned with the water overflow pathway.

Later, Sealand had plastic plugs to close off the porcelain overflow holes, and changed rubber gasket to eliminate the two small holes. Black plastic base design was modified to seal off the water trap holes, but the indentation is still there, but closed off.

Sealand later redesigned porcelain bowl where the overflow holes were removed. But to our 'discomfort' slightly increased the front height of the porcelain bowl. Along with the new bowl redesign, the backflow preventer on the back of the porcelain bowl was significantly redesigned, requiring a shorter replacement backflow preventer that mounts differently.

Our choice was to keep the original slightly slanted bowl, but did not want the bowl overflow function. We replaced all new parts, and kept just the original porcelain bowl. To seal off the overflow holes, we sealed the overflow chambers with a lot of silicone sealer poured in from bottom and from top, then closed it off with Sealand plugs. We still have to use the longer, older design backflow preventer.

We continue to like our Sealand 511 with its larger valve opening and deeper bowl. The large valve opening can make it easier when flushing larger quantiles. The pedal actuated valve works well and flushing parts are easily user-installed.

Re: Sealand/Dometic 511 toilet question

Reply #4 –
Part numbers for Sealand 511 toilet replacement parts:
Vacuum break with extension is for original model 500

385 318 162   Ball, Shaft, & Cart, white, INCLUDES spring cartridge kit (385 236 096)
385 320 325   Vacuum Break with extension for original model 500
385 319 055   Vacuum Break with extension & new sprayer hose & handle for original model 500
385 314 349   Water Valve Kit
385 310 063   Floor Flange Seal Kit
385 311 462   Seal Replacement Kit (bowl to base w/ ball seal)
385 345 377   Hose supply white, don't buy, use Lowe's hose if needed
385 236 096   Spring cartridge kit only

Re: Sealand/Dometic 511 toilet question

Reply #5 –
I have an actual 511 parts manual, but it says nothing about that plug in the back or its function.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Sealand/Dometic 511 toilet question

Reply #6 –
Sealand 511 is similar to its earlier version, model 500. Assume if the bowl has overflow holes is could be model 500.

Don't think the overflow plugs were ever a part number as they were something Sealand which used to have good call-in customer service, offered to mitigate any problems customers were having with the overflow holes.

Re: Sealand/Dometic 511 toilet question

Reply #7 –
Correct. I never was told about any part number for the plugs. But, when I called I was told that they would be sending them because the 511 base did NOT have any outlet to drain the liquid that would/could accumulate in the base. Unless one was willing/able to get down on the floor and periodically remove the drain plug and cap w/seals (Part #316142) and let the liquid drain out on to the nice blue shag carpet installed by FOT.
Hence, the overflow plugs.
But, now that I know what the drain plug does, and also know that some liquid might/does get in that area, and also that the floor is now tiled instead of carpet, I will remove the drain plug and check for liquid in the fall before putting the coach in storage for the winter up here.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Sealand/Dometic 511 toilet question

Reply #8 –
Not familiar with drain plug & cap w/seals mentioned. Is it part of the plastic base? Cannot picture where it is located. Our toilet uses a short base, and the toilet is mounted on a box made of ¾" plywood to allow for an above floor ABS angle drain pipe.

For the porcelain overflow plugs, we do not feel secure they would be watertight, so we used silicone sealer on plug and in hole.

Re: Sealand/Dometic 511 toilet question

Reply #9 –
The porcelain overflow plugs are flexible, maybe rubber. So I used some silicone adhesive sealant on them when I installed them three or four years ago.
Their locations are so high up from the bowl bottom that I doubt any water even touches them unless it is during a flush. One would have to deliberately hold the water valve open to get water high enough to touch the plugs.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Sealand/Dometic 511 toilet question

Reply #10 –
Hi, I was revering to

"Unless one was willing/able to get down on the floor and periodically remove the drain plug and cap w/seals (Part #316142) and let the liquid drain out"

Wondered where the above "drain plug" is located.

Thanks, Barry

Re: Sealand/Dometic 511 toilet question

Reply #11 –
If you can reach down near the floor, at the left rear of the base, you will feel a round recess that has a flat bladed screwdriver slot in the end of the plastic plug. There is an o-ring on this plug that you will see if you remove the plug. Point your screwdriver towards the right as you approach the round cavity from the left.
If one thinks of a clock as you look down at the base, the cavity is located at about 10-11 o'clock on the back of the base and goes straight left to right, not towards the center of the base.
If you have the small owner's blue and white manual, look on page 12, lower left corner, and you will see item #12.
Over in the right bill of material, item #12 is listed as 316142, Kit, drain plug & cap w/seals.
OKAY, my next post is the 511 manual page 12.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Sealand/Dometic 511 toilet question

Reply #12 –
Here is page 12
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD
 

Re: Sealand/Dometic 511 toilet question

Reply #13 –
Thanks for the toilet base drain hole location. 

I was not aware it was there, but found it and took the attached photo with flashlight & mirror.  The drain hole is to the right of the flange bolt & nut. 

Since our base is new style with the top drain holes sealed off, I see the bottom drain hole is also sealed off.  Sealed means during manufacturing, the plastic mold shows location, but they were never opened.

Zooming in on photo shows the hole is sealed.