We did not capture the procedure for flushing the holding tank with seawater for our 2003 Beneteau 361 when we took ownership. Can someone help? Thanks.
B361 Holding Tank Flush Procedure
- Thread starter 361BenGary
- Start date
Not sure what you're asking... Do you mean you want to know how to use sea water to thoroughly rinse out the tank, flush out any sludge?
Are you referring to dumping & flushing the holding tank at sea?
I chartered a Beneteau 331 that likely had the same setup as the 361.
There should be a macerator pump installed in the head under the sink. Turn on the macerator breaker on the DC panel. Unlock and position the "Y" valve, under the sink in the lavatory cabinet, for overboard discharge. There should be a diagram on the lavatory door under the sink or on the "Y" valve depicting the position of the lever on the "Y" valve for overboard discharge. Activate the macerator pump by depressing and holding the momentary switch (not the shower sump switch) located on the side of the lavatory cabinet. If you want to rinse the holding tank with sea water after dumping, reposition the "Y" valve for discharge into the holding tank, add water to the head, and flush it into the tank, then repeat the same process to discharge the seawater overboard.
Two things to note regarding USCG & local regulations. First, the "Y" valve has to be physically locked into holding tank position, so that no one can operate the "Y" valve except for the skipper or someone authorized by the skipper. Second, the usual limit for overboard discharge is 3miles offshore; however, anywhere on the Gulf Coast of Florida, the limit is 9 miles offshore. If you don't have a pump installed, you will not be able to dump the tank overboard, you will have to pump out at pump station in a marina. Hope this helps.
I chartered a Beneteau 331 that likely had the same setup as the 361.
There should be a macerator pump installed in the head under the sink. Turn on the macerator breaker on the DC panel. Unlock and position the "Y" valve, under the sink in the lavatory cabinet, for overboard discharge. There should be a diagram on the lavatory door under the sink or on the "Y" valve depicting the position of the lever on the "Y" valve for overboard discharge. Activate the macerator pump by depressing and holding the momentary switch (not the shower sump switch) located on the side of the lavatory cabinet. If you want to rinse the holding tank with sea water after dumping, reposition the "Y" valve for discharge into the holding tank, add water to the head, and flush it into the tank, then repeat the same process to discharge the seawater overboard.
Two things to note regarding USCG & local regulations. First, the "Y" valve has to be physically locked into holding tank position, so that no one can operate the "Y" valve except for the skipper or someone authorized by the skipper. Second, the usual limit for overboard discharge is 3miles offshore; however, anywhere on the Gulf Coast of Florida, the limit is 9 miles offshore. If you don't have a pump installed, you will not be able to dump the tank overboard, you will have to pump out at pump station in a marina. Hope this helps.
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You don't necessarily need a pump (though you can install one if you need) to empty the holding tank. Gravity can do this once you open the seacock. There are two versions. See attached pictures. I have the version with one throughull/seacock.
We have 3 hull valves under the sink and then the "Y" valve. No macerator pump. We do have a hand pump to pump waste overboard. The fwd valve is the seawater intake. The aft valve is the discharge from the holding tank thru the hand pump overboard. Not sure what the middle valve is for. We were told that the procedure to pump overboard is as follows:
1-open the aft valve
2-move the "Y" valve to the outboard position (away from you)
3-use the hand pump to pump overboard
This procedure works, but looking at the diagram, it looks like the pump is fed directly from the tank and the "Y" valve is not needed for this procedure.
We are looking for the procedure to flush the holding tank directly with seawater (without pumping water thru the toilet).
Thanks for the help.
1-open the aft valve
2-move the "Y" valve to the outboard position (away from you)
3-use the hand pump to pump overboard
This procedure works, but looking at the diagram, it looks like the pump is fed directly from the tank and the "Y" valve is not needed for this procedure.
We are looking for the procedure to flush the holding tank directly with seawater (without pumping water thru the toilet).
Thanks for the help.
I've posted it here many times...and included it in my books (see link in my signature). You have to add water to the tank via the deck pumpout fitting--'cuz that sends the water into the tank at the bottom to stir up any sludge...there are two ways to do it. After pumpout, use a hose (NOT a hose used to fill water tanks!) to put a few gallons of water into the tank...pump that out. Repeat...repeat...till you're pumping out clean water. You'll need a washdown pump to use sea water. Again, put a few gallons into the tank via the deck pumpout fitting, start the macerator pump and let it run while you continue to let the washdown pump add water to the tank till it's thoroughly rinsed out. You must be at sea outside the "3 mile limit" to do this legally.
Using gravity to empty the tank only works if the entire tank is above the waterline (and again, only legal outside the "3 mile limit"). If any part of it is below waterline, opening the seacock will flood the tank with sea water instead of emptying the tank. Leaving the seacock open while underway can force enough water into the tank to fill it and send a real mess all the back into the toilet.
Absolutely agree with the procedure on how to flash using fresh water via the deck fitting (the "NOT a hose used to fill water tanks" really made me lough!!).
The water line is at approximately the level of the toilet (slightly below in fact) so the entire tank is above the waterline.
Attachments
Oddly enough my head pump out hose connects to the BOTTOM of my holding tank (no tank-top dip-tube). Not real happy about that as the hose always contains some effluent and is subject to permeation. But it will make it easy to install a Y-valve for overboard dumping of contents.