On my 2002 4100, there is a bilge pump in a sump located in the mid ship bilge. From there the water is pumped into a gray water sump box w/ pump to overboard. Why are there two pumping facilities to handle the gray water? The primary bilge pump needs to be replaced, but I may send the effluent directly to the gray water box which is located in the engine compartment. Thanks
Scotty
I just realized that I need the sump with pump to push the waste water to the gray water tank which is about 15" away up a slight incline. So back to the drawing board. There is no other option to send it directly overboard. thanks for the reply.
Scott
This is the same setup on my 3700 Open. As you said, it's easier to pump the shower, head floor drain, sink and A/C condensate drains through a single hose to the greywater sump than it is to run all five back there.
It may be possible to do that, but you have to take into account the distance from the source to the sumps and height above the sump the source is. If the source is lower than the grey water tank, then you will have to drain to a smaller sump box and then pump the water to the grey water tank. I believe the shower is lower than the grey water tank, so you have to have a sump below the shower. The other issue is distance. A head sink located in the bow is not going to drain very well to a grey water tank located in the engine room 30 feet away. Grey water tanks are not needed in many cases, but they do reduce the number of thru-hull fittings up and down the sides of the boat. Every fitting is a possible leak. If I had my way, everything would drain into a single manifold and then drain to single tank or thru-hull for a clean set up with only one or two thru-hulls, but many layouts don't allow this type of set up.