H340 Grey Water Management

Jul 29, 2004
406
Hunter 340 Lake Lanier, GA
The Hunter 340 did not come from the factory with a system for pumping grey water overboard, including discharges from the shower drain, refrigerator drain, and air conditioning drain. The first two drained into the aft (upper) bilge, which then drained through a limber hole to the main deep bilge where the Rule bilge pump them sent overboard, always leaving an inch or so of water and soap scum, etc. Despite using a wet/dry vac when leaving the boat, I still had to clean the bilge a couple times a year and changed the float switch more times than I care to remember. Plus I risked getting a "Peggie demerit" as she frequently says not to drain the shower into the bilge. It only took me 15 years of ownership to decide to do it. :)

A few years ago member artboas was singing the praises of the Whale IC pump with 2 way manifold and a couple of other 336/340 owners posted they were going to install it, but didn't report back. https://forums.sailboatowners.com/index.php?threads/h340-sump-box-install.137590/ So this post is to close that loop if any others want to make this improvement.
It requires drilling a hole in the hull for a new overboard discharge, connecting the various drains together into the manifold (all different sizes of course), drilling some holes through a stringer to route the discharge hose and running some wiring.

Started by pulling the back of the closet apart to decide where to drill the new hole for the discharge hole. I put it at the same height as the existing bilge pump discharge and about 6 inches aft. New discharge on the left
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Inside view in the closet after installing the mushroom fitting and hose.
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Then I ran 1 inch ID smooth wall reinforced hose to my chosen location for the pump, which was under the main floor, under a screwed down section adjacent to the upper bilge. I bent up a piece of plexiglass for mounting the pump and lag screwed into the stringer, also cut a piece of hose to stand vertically under the plexi to take some weight off the screws and provide a little shock absorber action. View looking inboard
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I spent some time at Home Depot's plumbing dept selecting a bunch of adapters and a tee to get the refrigerator drain and AC drain tied together and then to the forward side of the manifold. The manifold has 1 inch hose connections (smooth, not barbed for some reason) so the shower drain went directly on the aft side. To get the manifold as deep as possible, I used 5200 to glue a PVC elbow on the bottom of the manifold, angled to line up with the hose to the pump. Again, I bent up a piece of plexiglass to mount the manifold, the lag screwed into the stringer under the galley drawers. Sorry, picture comes in upside down no matter what I do... View is looking to port, toward the stringer under the galley counter.
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I don't have an autopilot, so I used that breaker for the power to the pump. The manifold has an electronic sensor to detect water, and turns the pump on automatically whenever water is detected. Here's an overview of the Whale system installed
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I finished the install last week but so far it works as planned. The pump/manifold was about $230 at Hodges Marine, and I spent another $130 or so on hose, clamps, wire and plumbing fittings.
 
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