[C320-list] Holding Tank Flooding

[Utility Email]

The holding tank is below the waterline.  I bet it is filling through the macerator pump.  

I always keep the holding tank through hull closed unless we are using the macerate pump.  It is a pin in the neck to access, but I would not want to trust our boat to a check valve within a macerator pump.

I would close this valve, especially since you use a dock attendant to pump the system. 

Dave

S/V Emily Ann
2007 C320 MK  II, No. 1107
Mukilteo, Washington



David B. Swanson, P.E., S.E.
Principal, LEED AP, F. SEI
Director, Structural Engineering

Reid Middleton, Inc.
(425) 741-3800 office
(425) 741-5011 direct
(425) 508-7971 mobile

www.reidmiddleton.com

Washington | California | Hawaii | Alaska


> On Jul 19, 2016, at 1:25 PM, Kaare Wold <sailor3952 at charter.net> wrote:
> 
> Skippers,  Recently we noticed that our holding tank fills with water when at rest at the dock.  At first, thought our dock attendants failed to pump out.  We have an AccuGage digital monitor on all tanks.  Love that setup! We had the tank pumped, while we were present,  and as the tank was being pumped out, I could see the AccuGage digital level drop from 3/4 to 1/2 down to empty. A couple days later, it was back to 3/4 full without any personal use whatsoever.  The macerator thruhull had been open all the time, although we never use that device.  All thruhull are opened for winter layup and I never closed it after spring launch.  I now closed the thruhull, had the tank pumped out again and.....bingo...,  the tank remained empty.  Any ideas from our knowledgeable group???   Could there be a check valve in the macerator pump that is leaking?    Looking for some suggestions or comments from someone that may have experienced the same problem.  Thanks to all for your comments.
> Kaare & Mary Wold
> Sheet Music, #945  Sturgeon Bay, WI