Installing 2 waste pumps
- Thread starter freyakitkat
- Start date
If you're planning to do a lot of "blue water" voyaging, I'd put a y-valve in the toilet discharge line that will let you flush directly overboard at sea, only going into the tank when you have no choice.
However, whether you do that or not, you shouldn't need a backup manual pump--although it never hurts to have a backup manual BILGE pump, and most manual diaphragm pumps can do either--if you do three things: 1. maintain it, which requires rinsing it out with clean FRESH water every chance you get... 2. carry a spare and put a shut-off valve ahead of it in the tank discharge line so you can swamp it out if you need to...'cuz no one ever finds out they need to when the tank is empty...and 3. carry at least one kit for it so you can rebuild the failed pump, thus always keeping a spare pump on hand.
And if your toilet is a Jabsco, carry at least one spare pump...if it's a PHII, you shouldn't need to carry a spare anything except maybe a rebuild kit and a tube of SuperLube teflon grease...and you shouldn't need the rebuild kit if you put one in before you depart, 'cuz that toilet only needs rebuilding every 5-6 years if it's kept well lubricated.
However, whether you do that or not, you shouldn't need a backup manual pump--although it never hurts to have a backup manual BILGE pump, and most manual diaphragm pumps can do either--if you do three things: 1. maintain it, which requires rinsing it out with clean FRESH water every chance you get... 2. carry a spare and put a shut-off valve ahead of it in the tank discharge line so you can swamp it out if you need to...'cuz no one ever finds out they need to when the tank is empty...and 3. carry at least one kit for it so you can rebuild the failed pump, thus always keeping a spare pump on hand.
And if your toilet is a Jabsco, carry at least one spare pump...if it's a PHII, you shouldn't need to carry a spare anything except maybe a rebuild kit and a tube of SuperLube teflon grease...and you shouldn't need the rebuild kit if you put one in before you depart, 'cuz that toilet only needs rebuilding every 5-6 years if it's kept well lubricated.
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You wouldn't be using the toilet to dump the tank...you'd just be flushing the toilet directly overboard INSTEAD of into the tank. And yes, you definitely want to keep the plumbing as simple as possible...your original plan would be a convoluted nightmare!
One y-valve in the TOILET discharge line to give you a choice of flushing overboard or into the tank...and one line coming out of the TANK that has a y-valve in it--one side going to the deck pumpout, the other side through your overboard discharge pump, to the same thru-hull the toilet uses.
Better yet, if the tank is empty and clean you can eliminate the y-valve in the TANK discharge line by putting a second discharge fitting in the tank (it's VERY easy to do, thanks to a gadget called the Uniseal UNISEAL )...run the hose from one discharge fitting to the deck pumpout, run the hose from the other one directly to the overboard discharge pump.
If we need some conversation to sort all this out, send me a PM.
Peggy: Really? a gasketed friction-fit thru-wall push fitting in a waste tank? Good grief that just sounds like a recipe for a bilge full of pooh! There is like 30" of head inside my tank and if the vent ever clogs and some lubber decides to push harder on the head pump ...I don't even want to....I need to set up a system to discharge my tanks offshore (not just the head).
The Uniseal has been--and is being--used successfully to relocate holding tank fittings for a couple of decades, but if you don't want to use it, fine with me...it's your boat. However, there's no way your blocked vent scenario could blow it out because any pressure would only send waste out the hose that's in it!
I laid out the right way to do that using a y-valve in the tank discharge line. Adding a second tank discharge line would just be a way to eliminate the second y-valve.