Author Topic: holding tank Pump out  (Read 6284 times)

Noelio Abrunhosa

  • Able Seaman
  • ****
  • Posts: 108
  • Karma: +0/-0
  • Boat Model: Bavaria 38 cruiser
  • Boat Year: 2005
holding tank Pump out
« on: September 20 2017, 08:24 »
hi. On Po-Go the holding tank was disconnected and the heads plumbed straight to the outside. i wish to bring the tank back in operation. where would the pump out fitting be installed on a bavaria 38? also any one got the correct plumbing layout? i know on the beneteaus there is a valve that allows you to chose flush to tank or flush to outside.

Kind regards


Abby

mikeiso1192

  • Second Mate
  • **
  • Posts: 44
  • Karma: +0/-0
  • Boat Model: Bavaria 38
  • Boat Year: 2004
Re: holding tank Pump out
« Reply #1 on: September 20 2017, 22:46 »
Hi Abby
I would gladly come down to Brighton and guide you through where to heads / holding tank pipework goes.
Mike

Lyra

  • Old Salt
  • *****
  • Posts: 349
  • Karma: +0/-0
  • Boat Model: B36
  • Boat Year: 2004
Re: holding tank Pump out
« Reply #2 on: September 21 2017, 09:50 »
On the Bavarias that I know it is always the same setup - the holding tank is installed above water level so emptying is gravitational and it is attached so it is simply a very wide extension of the flushing pipe:
Flushing pipe goes from bowl to top of tank
Bottom of tank is connected to outlet seacock
If the seacock is open then everything flows through the tank directly out. If it s closed the tank begins to accumulate until the seacock is opened agan.
There is also another pipe going from the bottom of the tank and bending upwards to an opening on the deck for pumpout using an external pump.
And there is a small diameter vent pipe

I know the setup that you mentioned regarding Beneteau (I saw it also on Huneter and Moody), but in these case the holding tank was below water level and emptying it involves a pump.
It seem to me that setting a dual function system with a gravitational tank would require 2 additional valves and a Y connection:
A 2 way valve before (and above) the tank will determine if bowl flushing goes to the tank or directly to the seacock
A simple valve at the outlet of the tank will determine if it will drain or hold its contents. I think this valve can be eliminated if you accept that once you switch to using the tank it will have to be drained before you can switch back to direct flush.
The Y connection "leg" will go to the seacock with its "hands" receiving from either the tank or the bowl.

Personally I have been using the original Bavaria setup with no problems, except for once when the tank got clogged due to calcification.
S/Y Lyra
B36 / 2004

Yngmar

  • Administrator
  • *****
  • Posts: 1595
  • Karma: +22/-2
  • Boat Model: 40 Ocean
  • Boat Year: 2001
Re: holding tank Pump out
« Reply #3 on: September 21 2017, 14:59 »
Ours is like Lyra describes, plus there's a Y valve mounted on the sink bulkhead next to the toilet, labeled "Sea" and "Tank", which diverts the toilet output either directly to a seacock or into the top of the holding tank. The whole setup works very well including the gravity draining at sea by opening the tank outlet seacock - we then usually pump a bit of seawater into the tank via the toilet before we close it again.

The pump-out fitting is on the side deck, directly aft of the holding tank, which is behind the shower wall.
(formerly) Sailing Songbird  ⛵️ Bavaria 40 Ocean (2001)

Salty

  • Old Salt
  • *****
  • Posts: 1216
  • Karma: +3/-1
  • Boat Model: Bavaria 36
  • Boat Year: 2002
Re: holding tank Pump out
« Reply #4 on: September 22 2017, 11:33 »
Thanks for the descriptions Lyra and Yngmar, this is a modification I've been thinking of doing now for some time. My B36/2002 already has the black water tank in place, presumably from new, but with no connection either from toilet or to sea, and no pump out deck fitting. From your descriptions it sounds like it could be a relatively easy job to put the connections and plumbing in place.
Do your tanks have an access hatch in order to permit cleaning in the event of a blockage?

Yngmar

  • Administrator
  • *****
  • Posts: 1595
  • Karma: +22/-2
  • Boat Model: 40 Ocean
  • Boat Year: 2001
Re: holding tank Pump out
« Reply #5 on: September 22 2017, 11:46 »
There is a round access lid on the tank top itself, but it is under the sidedeck and inaccessible unless the tank is removed.
(formerly) Sailing Songbird  ⛵️ Bavaria 40 Ocean (2001)

Salty

  • Old Salt
  • *****
  • Posts: 1216
  • Karma: +3/-1
  • Boat Model: Bavaria 36
  • Boat Year: 2002
Re: holding tank Pump out
« Reply #6 on: September 23 2017, 05:52 »
Thanks Yngmar, I'll see if I can find the access just to confirm its there, and may make that modification to the plumbing over the winter.

Clivert

  • Able Seaman
  • ****
  • Posts: 115
  • Karma: +2/-0
  • Boat Model: Bavaria 34
  • Boat Year: 2001
Re: holding tank Pump out
« Reply #7 on: October 05 2017, 14:39 »
I am fitting a tank on our 3 cabin 34 unber the forward berth but am discouraged from fitting a pump out because a) the facilities are few and far between and b) my marina charges £90 a go.
Hardly likely to encourage going green.

Noelio Abrunhosa

  • Able Seaman
  • ****
  • Posts: 108
  • Karma: +0/-0
  • Boat Model: Bavaria 38 cruiser
  • Boat Year: 2005
Re: holding tank Pump out
« Reply #8 on: October 06 2017, 13:31 »
hi.

i thought the same but some marinas in europe insist on it
regards

Abby