1-9. Safety, Care, and Handling. Safety precautions must be observed at all times while performing maintenance.
General WARNINGS and first-aid data appear in front of this manual. Review all safety information before starting any
task. Carefully read through an entire maintenance procedure before performing any maintenance function. Make sure
the task can be done safely. All WARNINGS, CAUTIONS, and NOTES are of great importance to your safety and the
safety of the equipment.
SECTION III. PRINCIPLES OF OPERATION
Overview of bilge/ballast pump assembly.
The Principles of Operation section will tell you basic information about how this assembly works.
1-10. General. The bilge/ballast system is pressurized by a close coupled electric pump with associated piping, valves,
indicator gauges, and manifolds. With valve alignment arranged for ballasting, the pump will take suction from the sea
chest and discharge water through the piping into each of the seven ballast tanks until filled to the desired capacity. With
the valve alignment arranged for trimming the vessel, the pump will move water through the system to strategic tanks or
discharge the water directly overboard until the vessel has reached the desired trim. With valve alignment arranged to
pump bilges, the pump will take suction through a pipe-mounted strainer located in the lowest accessible point in the
bilges of the engine room, auxiliary machinery room, bow thruster machinery room, and tunnel. Water will discharge
directly overboard. (Reference TM 55- 1905-223-24-18, Basic Craft Hull and Outfitting.)
a. Bilge/Ballast Pump Assembly. The bilge/ballast pump is controlled locally on or near the pump and in the
engine room control booth. Pressing the START pushbutton energizes the electric motor, which is close coupled to the
pump. The shaft in turn drives the pump, which takes a suction from the sea chest, bilge strainer, or ballast tank
according to desired service.
b. Auxiliary Bilge/Ballast Fire Pump Assembly. One of two fire pumps serves as an auxiliary bilge/ballast pump.
See TM 55-1905-223-24-12, Fire Pump Subsystem.