Bilge pumps are normally installed at the lowest part of the bilge, which makes perfect sense given that this is where any water that gets into the hull will naturally tend to once it is inside.
The primary function of a bilge pump is to remove any incidental water that may be present in the bilges. This water may originate from packing gland leaks, precipitation, or other sources. It is quite possible that you will have more than one bilge pump if your vessel is outfitted with a number of separate bilge compartments or sections.
Do Not Rely On Your Bilge Pump
Do not mistake your bilge pump with an emergency pump, which has a far higher ability to remove water from the vessel. Bilge pumps can buy you some time in the event that you take on significant water, allowing you to do tasks such as putting on life jackets or calling for assistance.
Check And Test Your Bilge Pump
At regular intervals, do checks to ensure that all bilge pumps are working properly (preferably every time you go out, but quarterly or semiannually at a minimum). It is especially important to do this if the vessel is maintained in a slip. In the testing, rather than just turning on the pump and listening for the sound of the motor working, there should be confirmation that water is being sent overboard.
The easiest way to ensure that your bilge pumps continue to function properly is to do periodic maintenance on them before any problems arise.
The corrosive atmosphere of the bilge is a difficult environment for anything electrical, thus it is important to examine all cables and connectors for corrosion and to only use marine-grade heat shrink-style connectors (no wire nuts or electrical tape joints).
Note: Disassembling a pump in order to perform maintenance is typically a simple process. However, certain pumps are more difficult to disassemble than others, therefore it is important to read all instructions very carefully in order to prevent making any assembly errors.
How Much Water Will Your Bilge Pump Move
The amount of vertical distance that bilge water needs to be pushed before it can be pumped out is referred to as the “static head,” and it is one of the most important factors that contributes to this decreased production. A static head of just 2 feet may cut the output of a 500 gph pump in half, while a static head of 15 to 20 feet can potentially render the pump completely ineffective.
It is not necessary to assume that a bilge pump will really pump the specified amount of water, such as 500 gallons per hour, simply because the manufacturer has rated it to do so. Although laboratory testers might be able to extract 500 gph from a pump without the use of a discharge pipe and under ideal conditions, doing so in the real world is a whole different story due to the many limitations that are there.
