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Liberty Bay bilge pump discharge filter.


better suited to PDPs. The condition of these filters can be monitored with a pressure gauge installed between the filter and the pump. A Best-of-Both-Worlds Solution:


also may have a non-return valve incorporated into them so the water between the pick up and the pump does not drain back into the bilge, which solves the pump recycling problem and keeps the pump primed. The hose must have sufficiently thick walls to avoid collapsing under suction. Dry Bilges can be Green too:


Getting the maximum water out of the bilge may mean pumping petroleum products with it. The subsequent pollution could be dangerous to the environment and your bank account. A small quantity of engine oil or diesel will cause a large sheen on the water. One cup of oil can cause a bright colored sheen for a radius of 50 feet before it disperses. The solution to this is an oil contaminants filter (Liberty Bay Solutions) which will allow the water to pass overboard while trapping the problem in the filter. These filters cause some back pressure and therefore are


Use a duel pump system using a submersible pump for volume, 4000 gph, with a float switch or sensor mounted a couple of inches up from the bilge, and a PDP with it’s pick-up and sensor mounted as low as possible with an oil contaminants filter in the discharge hose. This would give you both redundancy (back-up) and be more cost effective. Both pumps could use the same discharge thru-hull fitting. This would keep your boat dry at the dock and give you time to fix even a major leak. (a 1” hole 5’ below the waterline may admit 44 gpm / 2640 gph). Normally we think bilge pump


when we should be looking at it as the “Bilge pump system”’ So here’s to a dry bilge and a clean environment.


Jack Wilken has a degree in Technical Oceanography- Fullerton, CS / Ex USCG, Boat builder (Westsail QC & Engineering Manager / Pacific 41. Alex Wilken Was born in Costa Rica


in 1981 and cruised with the family until 2004. He has a degree in Marine Carpentry- Wood Construction Center, SCCC, and 100 ton Masters License. In 1979, Jack Wilken left from Seattle in


a Yamaha 33 to Martha’s Vineyard / 1983- 2004 French Canals to Mediterranean and Western Mediterranean in Pretorian 35 & 50’ steel ketch(Galapagos 50) Jack and Alex own Seattle Boat Works jack@seattleboatworks.com


multihulls classic sails offshore spec


load path one design


Rush Sails Your Northwest Neil Pryde Sails Agent Scott Rush


206-719-8436 rushsails@aol.com


Local Service Global Reputation


Pick up or Strumbox with non return valve. 48° NORTH, FEBRUARY 2011 PAGE 47


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