Cruisers Forum

Join CruisersForum Today

Thread Tools Rate Thread Display Modes
Old 25-11-2015, 10:54   #1
Registered User
MickMeck's Avatar

Join Date: Aug 2013
Location: Mechanicsburg, PA
Boat: Jeanneau 43 DS
Posts: 6
Waste Systems

This is a general question. I have two heads. The waste lines go to a Y valve which directs the waste either overboard or to a holding tank. The holding tank has an access point topside for pump outs or a seacock down below to dump overboard. My question is - Why? It seems that if the holding tank dumps to the sea then the waste line should go directly to the tank from the toilet. This would eliminate 4 connection points (potential leaks) and about 10' extra of waste hose (which would contain waste products).

I would propose to go directly to the tank from the toilet. What problem will I have? Am I missing something?

Also, the seacock from the bottom of the tank is close to the thru hull. This means that there is always waste in the hose. Why not have the seacock at the bottom of the tank?

Feedback is greatly appreciated.

MickMeck is offline   Reply With Quote
Old 25-11-2015, 11:30   #2
Registered User
Dsanduril's Avatar

Join Date: Aug 2011
Location: South Pacific
Boat: Outremer 50S
Posts: 1,541
Re: Waste Systems

Ours is currently plumbed the way you propose (and formerly had a 'Y' valve as you describe). If the tank can empty fully by gravity then it works fine. A couple of minor things I've observed:
  1. There is about 6-8 feet of discharge pipe/hose from the head to the tank. So, to fully flush you have to pump enough water to clear that hose.
  2. If the tank is high enough to drain by gravity then you are likely pumping uphill from the head. Even if that line is full of clean water, when you have to work on the head you have to manage to drain it out somehow. When we had the 'Y' valve the distance to discharge was about one foot, and the elevation change was about 6", so easier to clear the line.

For the tank drain, a valve at the tank will keep the line clear of waste when using the tank, but you also need one at the through-hull in case of problems. So, up to you if you want two valves or not. In our case we have one, and have not had permeation problems or anything like that.

Dsanduril is offline   Reply With Quote
Old 25-11-2015, 11:50   #3
Registered User

Join Date: Apr 2013
Location: So Cal
Boat: Catalina 30
Posts: 950
Re: Waste Systems

Some folks like the Y valve so they never put waste in the tank.

I'm not one of them. I eliminated the Y valve as you propose. head -> tank -> macerator. I have a macerator 'cause the tank is too low to gravity drain.

Since I live in the land of poo police, this works out well. The poo police ask to see the Y valve and I get to say "I don't have one."

Every now and then, outside of 3 miles, I turn the macerator on. I've got a deck pump out too but macerating is easier. I'd rather have a gravity drain though.
jeepbluetj is offline   Reply With Quote
Old 25-11-2015, 12:08   #4
Senior Cruiser
Cheechako's Avatar

Cruisers Forum Supporter

Join Date: Aug 2006
Location: Skagit City, WA
Posts: 20,042
Re: Waste Systems

Yes good point. I have had systems that go only to the tank, then you can pump out or go thru a seacock below the tank. No problem and I hate sticky Y valves!
"I spent most of my money on Booze, Broads and Boats. The rest I wasted" - Elmore Leonard

Cheechako is offline   Reply With Quote

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
How Popular Are Marine Waste Treatment Systems? ksanders Plumbing Systems and Fixtures 28 01-01-2013 13:35
Oily Waste Management markpj23 Engines and Propulsion Systems 13 04-06-2007 12:37
Waste Tank and Hose Replacement Project Latitude9.5 Plumbing Systems and Fixtures 5 06-08-2006 11:26
Metric waste fittings Will Burton Construction, Maintenance & Refit 5 01-09-2005 23:27

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 23:16.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.