Holding tank blockages

[stevem]

This morning found that the holding tank is blocked. Tank totally full and small jet of water almost a spray jeting out of round hatch at top of tank. I could not get hatch cover off and did not want to risk damaging it by not knowing the correct way of removing it. I imagine that it is screwed in.

Has anyone had a tank blockage and any ideas of the best solution to empty tank and clear the blockage ?

[njsail]

We just finished replacing all the sanitation hose and cleaned out the holding tank today.  It comes out easily and the big round cover on top screws off if you can get access to it.   If you have a blockage somewhere do you know;
1. Is the holding tank empty?  if not empty it first
2. When it filled up did the overflow go out the overflow vent?
3. do you have a Y valve or lectrasan that might have a loop back?  Might sound obvious but figure it's worth a look.   
maybe it's time to start pulling hoses to see what's blocked.

i was a little disturbed that after removing the holding tank one of the 2" sanitation fittings just fell off.  It was screwed in with only 1 thread. what a mess that would have made.   Now I changed the configuration to eliminate the sanitation hose from from the tank to the macerator.  We screwed the mascerator directly into the bottom of the holding tank.  One less hose to deal with.

[Moodymike]

Had to make up a tool to remove the inspection cover. Basically two pieces of hardwood to fit the slots, these two were bolted to a domestic hot water tank element spanner, came undone easily due to the pressure low down, prior to this nothing would shift it . When the tank was full water came out of vent pipe had to release pressure by sucking excess out of deck outlet.  Long piece of pipe shifted obstruction. Never put toilet paper down unit.

[Brian]

Have you tried using your dinghy foot pump to blow air into the seacock outlet. 

[Sweet As]

We lived with this issue on our Bav36 and the necessary messy response for a while before fixing it completely by coverting to an electric loo with built in macerator. So I am assuming that you have a manual loo.

I took a while to find the best option for the conversion. Settled on a Raritan Sea Era conversion kit with remote inlet pump. It offerred the neatest fit in the space available. (we have the two cabin layout). Have never had a blockage yet and makes it all so much easier for everyone onboard.