I own a Hunter 420, built in 2000. For years the two holding tanks worked flawlessly. Recently, as far as I can tell the rear holding tank is running full and I think it is being flooded with sea water. The macerator empties it but it refills very quickly, again with must be sea water. Any ideas on the cause and the fix?
Constant refilling of seawater in holding tank
- Thread starter tadd5181
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Recent post on exactly this problem. Do a search.
The macerator act as a check valve but is now leaking. You should always keep the the-hull closed whether the pump is back flowing or not. In this case, it will solve the problem
The macerator act as a check valve but is now leaking. You should always keep the the-hull closed whether the pump is back flowing or not. In this case, it will solve the problem
Your sea cock ball valve is not shutting off.
It may appear to be closed.
Fix is change the sea cock.
Jim...
Are you saying not to open the valve when using the macerator to empty the tank and the tank will nonetheless empty?
+1 James. I had a macerator through hull that appeared open by the handle position, but the ball remained closed. Those valves work in a hostile environment and you may have the same issue with the handle closed but the ball open. Good luck.
No, no, no. Sorry if I was unclear.
Thru-hulls (all of them) should remain closed when you are away from the boat. This is for safety reasons. This will of course solve your problem Open the thru-hull to pump out and then close and leave closed until next pump out.
Macerators are weird beasts. When we are on the water for a month or more, I will sometimes forget to close the through-hull. Sometimes the tank will back fill and sometimes not. Just depends on what gets momentarily stuck in the pump when it shuts down as to whether it's going to seal or not.
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Macerator pumps are not check valves...the best they can do is slow down water that's being forced through them backward.
The overboard discharge thru-hull should always be kept closed except when actually dumping the tank. If you're closing the seacock and sea water is still filling the tank, it's a strong sign that the seacock is in need of repair/replacement.
--Peggie
The overboard discharge thru-hull should always be kept closed except when actually dumping the tank. If you're closing the seacock and sea water is still filling the tank, it's a strong sign that the seacock is in need of repair/replacement.
--Peggie