Holding tank changes for a Beneteau 311

[mario101]

Hello,
I have a Beneteau 311 year 2000. Great boat. The head is above waterline and holding tank way above waterline. Head goes overboard or in the holding tank via an Y valve (can be locked). Holding tank only can be emptied by pumping it out (from the bottom). Since I intend to travel (I am in south Florida) to various places (Dry Tortugas etc) I am concerned that once the tank if full and I am far away from a pumping station I may not be able empty the holding tank so I intend to add a macerator pump and another Y valve (direct the discharge to deck or overboard). This new Y valve also will have the option to be locked. I have a few questions to the forum since I am not an expert.
1. did anybody made changes to a similar boat? Any sugesttions , tips are welcome
2. it is ok with coast guard to have two Y valves locked (also I intend to keep the tru hull locked). I like to keep the existing arrangement head to holding tank/overboard via Y valve for maintenance purposes instead of passing all the time thru holding tank.
3. due to configuration (everything above the waterline ) there are no venting loops. If I add the macerator do I need to add a venting loop ?
4. the macerator usually has @ input port both threaded and barbed connections. Due to the psace constranints I need to come with a 90 degree adaptor (thereaded to hose) so I'll cut the barbed portion. (sorry stupid question - is this normal ? any issues with the warranty for the macerator ?)
Thank you,
Mario

 

[KD3PC]

the Beneteau 36CC of that vintage has the system you desire...perhaps some owners will step up with a picture. IIRC, mine was in the adjacent closet to the head and the holding tank was small 12-15 gallons, below that was three y valves. One directly from the tank to two below the tank.

one below went to macerator and overboard and Locked/dead end mode
the other went to the deck pumpout and locked/dead end.

That way there was no question about where the lock outs were nor could mistakes be made.

all connections on mine were barbed and clamped. there was still a vent to the tank and a loop. No 90's just gradual bends.

 

[mario101]

Re: holding tank changes for a Beneteau 311

Thank you. I'll try to find some 36 documentation. My holding tank is also in a closet adjacent to the head. However is a 31 so smaller and the space below holding tank is smaller than in a 36. I practically have 15 inches to install a macerator this is why I considering a 90 degree entrance - better than a sharp bent in the hose.
Mario.

 

[joker460]

My buddy has a 323 in Ft Myers. He has a macerator as a standard setup.

You might also look at the 323 manual (Beneteau Website) as it has the plumbing diagram.

Good Luck

 

[mario101]

Thank you. Just pulled out their manual. They are using one additional thru hull for macerator output. Wondering why? ("hate" additional hole in the hull).
I'll combine the macerator output with the existing one via a T.

 

[joker460]

You could use a "T" or better yet another 3 way valve so you can select either from toilet to overboard or holding tank to overboard. Depends on how you physically plumb it so to prevent backup into macerator discharge.

 

[Peggie Hall HeadMistress]

Why would a macerator pump be needed to dump a tank that's entirely above the waterline? It should be able to drain via gravity without any help from a pump...just open the seacock.

 

[mario101]

Peggie,
I was considering this. The bottom of the tank is routed right now only to deck. Thru hull is located lateral from the tank (roughly 2 feet). The bottom of the tank is ~ 12-14 inches above waterline. I need to use a Y-valve and the Y-valve with their 120 angle between prots will "eat" 1 -2 inches from the slope. So basically due to the fact that the liquid in the has a fluidity somewhat different from water and because I have this slope I am concerned that the flow may not be so smooth for gravitational discharge. A macerator will create the needed vacuum/pressure to speed things up and they are not expensive. But if u think that should be no problem I can use gravity initial and add the macerator later.
Thank you,
Mario