Blocked Toilet / Bordtoilette - Verstopfung beseitigen (Raske & Meyen - RM69)

How to unblock a Toilet on an Ovni 395

Wie funktioniert wieder das Bordklo
The boat-manual nor the toilet-manual does not cover this process!
I hope the hints below will help a firsttimer:

A job for 2 persons (or one who knows the job really good! (I always need an assistant) - best is someone the size of a little child (to fit in this place) with a strength of a bull (to connect and disconnect the hoses)
It took 4h!

I used following tools:
Biggest screewdriver on board and a normal one
30mm-adjustable Key for securing the adapter in the throughhole
Litle key for the hoseclamps
Wrench which is big enough to cover the hose
Tons of papertowels/toiletpaper
Big plasticbags to catch the water (check for holes before!)
Little watertight plasticbags to catch the water

A) Eat and drink
Do this before starting, because after starting you might not want to have a snack or even touch a dish ...

B) Check where the blockage is
We moved the 3-way-valve into the holdingtankposition (which took about 10 minutes in very tiny repeated steps, because it was nearly unmoveable).
Pumping into the holding tank was possible => so the blockage was in the between 3-way-valve and through-hull-valve.
I checked the outlet from the through-hull-valve from the water, just to make shure there is no monsterbarnacle blocking the exit (more hope than sense) => it would have been so easy, but we had to proceed ...

C) Cover up
We covered everything with papertowels and toiletpaper to prevent any liquids of traveling through the bildge.
We used plasticbags for catching liquids => worked fine!

D) Disconnect
That was actually the hardest part and took quite a while. The space is to limited to apply force only via arms. We took a wrench or a key as a basis for the big srewdriver to lever the hose in tiny steps out of the barb of the valve. Moving the hose left to right was more sucessful than trying to twist it of.

Cleary visible is the blockage cause: A buildup from some nasty material, hard as stone, which reduced the innerdiameter to a fraction of it´s volume

E) Beat it
That was the easiest part: We took the hose onto the bathingplattform and hammered the hose to destroy the unwanted structure inside, rinsed the particles out, hammered, rinsed, hammered, rinsed, hammered, rinsed, hammered, rinsed, hammered, rinsed ...
It was not necessary to use some acid.

F) Reconnect
That was actually the second hardest part. It was only possible to apply force via arms. We greased the inside of the hose with PTFE, but left 2cm free at the end where we appied a small quantity of Sikaflex. Moving the hose left to right was more sucessful than trying to twist it on.
After securing with 2 hoseclamps we smeared some Sikaflex on the hoseend.

If you want more infos (e.g. using muriatic acid and what does it do to skin), you can get them on the Yahoo "Southbound Group" with the search/topic: "calcium Build up".

Sideinfo, because we have not found something in Ovni395-manuals or the internet:
Holdingtank: How does it function
We learned from "Vanupieds" (Thank you!) that the only indicator for the level of the holdingtank is the ventopening => if the liquid comes out, it is full
Easy, but ugly!
The holdingtank is emtied by gravity via the through-hull-valve or can be pumped out via the deckfitting., © Dagmar und Christian Sahr,