Comprehensive Guide to Vessel Bilge System Troubleshooting

A vessel’s bilge system is responsible for collecting and pumping out any water that accumulates in the lowest part of the hull, known as the bilge. A bilge system is essential for preventing flooding, corrosion, and damage to the vessel’s structure and equipment.

If you want to learn more about vessel’s bilge system, please follow THIS LINK.

However, like any other system on board, a bilge system can malfunction or fail due to various reasons. In this article, we will discuss some of the common problems that can occur in a vessel’s bilge system, and how to troubleshoot and find the problems within the system.

Types of Bilge Systems

In general, a vessel’s bilge system consists of three main sub-systems:

  • Engine room bilge system: This system collects and pumps out the water that leaks from the engine room machinery, such as pumps, valves, pipes, tanks, etc. The engine room bilge system usually consists of a main bilge pump, a bilge well, a bilge manifold, a bilge alarm, and several bilge suction lines that are distributed throughout the engine room.
  • Cargo hold bilge system: This system collects and pumps out the water that enters the cargo holds due to condensation, leakage, or damage. The cargo hold bilge system usually consists of a cargo hold bilge pump, a cargo hold bilge well, a cargo hold bilge manifold, and several cargo hold bilge suction lines that are connected to each cargo hold.
  • Rudder trunk or bow thruster bilge system: This system collects and pumps out the water that enters the rudder trunk or the bow thruster compartment due to leakage or damage. The rudder trunk or bow thruster bilge system usually consists of a rudder trunk or bow thruster bilge pump, a rudder trunk or bow thruster bilge well, and a rudder trunk or bow thruster bilge suction line.

The engine room bilge system and cargo hold bilge system are interconnected and an isolation valve is fitted between these two systems. This allows the main bilge pump to be used for both systems in case of emergency. However, under normal circumstances, the isolation valve should be kept closed to prevent cross-contamination between the engine room and the cargo holds.

Common Problems in Vessel’s Bilge System

Some of the common problems that can occur in a vessel’s bilge system are:

    • Clogging and Blockages: One of the most frequent issues in bilge systems is clogging and blockages in the bilge pump and associated pipes. Accumulated debris, dirt, or even marine life can obstruct the flow of water through the system, leading to reduced pump efficiency or complete failure.
    • Bilge pump not working: Bilge pump failures can result from various causes, such as electrical malfunctions, worn-out components, or impeller damage. A dysfunctional pump can lead to excessive water accumulation within the vessel, risking its stability and safety.
    • Float Switch Malfunction: When bilge pump is running on AUTO mode, float switches are essential components that trigger the bilge pump to activate when water levels rise. Malfunctioning float switches can lead to either constant pump activation (even when unnecessary) or failure to activate when needed.
    • Leaks and Cracks: Leaks in the bilge system’s piping, hoses, or pump housing can contribute to the accumulation of water in the bilge area. Corrosion, wear, or cracks in these components can compromise their integrity and cause leaks.
    • Electrical Issues: Given the reliance on electrical components in modern bilge systems, issues like corroded wiring, faulty connections, or blown fuses can disrupt the proper functioning of the system.
    • Inadequate Maintenance: Neglecting regular maintenance can lead to the deterioration of pump performance and other system components. Lack of maintenance increases the likelihood of encountering issues over time.
    • Bilge alarm sounding: This can indicate that there is excessive water accumulation in the bilge due to leakage or damage.
    • Bilge water contaminated: This can be caused by oil, fuel, chemicals, or other substances that leak or spill into the bilge. This can pose a serious environmental and safety hazard, as well as damage the bilge system components.

Troubleshooting Vessel Bilge System Problems

    • Visual Inspection: Start by visually inspecting the bilge system, looking for any visible blockages, leaks, or damaged components. If possible, repair any damage that is causing water ingress using temporary or permanent methods such as plugging holes, tightening fittings, replacing gaskets, etc.

      Examine the pump, hoses, float switches, and electrical connections.

      Example of bilge pump

    • Testing Float Switches: Manually test the float switches by lifting them to simulate rising water levels alarms and pump control. Ensure that the pump activates when the switch is raised and deactivates when lowered.

    • Checking Electrical Connections: Inspect the wiring, connections, and fuses associated with the bilge pump. Corrosion or loose connections can impede electrical flow. Use a multimeter to test for continuity and voltage.

    • Cleaning and Clearing Blockages: If you identify blockages, clean and clear the pump, filters, pipes, and hoses thoroughly. Ensure that strainers are installed to prevent debris from entering the system.

    • Inspecting and Replacing Pump components: In case of pump failure, inspect the impeller (rotor) or stator for signs of wear, damage, or blockages. Replace it if necessary. Usually, the bilge pumps are volumetric type.

      Inspecting pump rotor

      Inspecting the pump stator

      Read more about this type of pump by following THIS LINK.

    • Pressure Testing: If leaks are suspected, perform a pressure test on the system to identify the source of the leakage.

      Bilge system pressure test

      Locating a faulty valve within a vessel’s bilge system requires a systematic approach involving careful observation, inspection, and testing. Here’s a step-by-step guide to help you find a failed valve in the bilge system:

        • Review the System Diagram: Familiarize yourself with the vessel’s bilge system diagram. Understand the layout of pipes, hoses, pumps, and valves. This will give you an overview of how the system is structured and help you identify potential points of failure.
        • Check for Visual Clues: Start by visually inspecting the bilge system components. Look for any signs of leakage, corrosion, rust, or unusual wear around valves. These visual cues can indicate the general area where a failed valve might be located.
        • Trace the Flow: Follow the flow of the bilge system from the source (where water enters) to the discharge point (where it exits the vessel). Identify valves along the way that control the flow of water. There may be multiple valves in the system, including inlet and outlet valves, as well as isolating valves.
        • Isolate Sections: Divide the bilge system into sections and isolate each section by closing or opening valves one at a time. For example, close the inlet valve and observe if the water flow stops. This can help you narrow down the area where the failed valve might be located.
        • Listen for Unusual Sounds: While the bilge pump is running, listen for any unusual sounds near the valves. A failing valve might produce a hissing, whistling, or gurgling sound due to the escaping water or air.
        • Check Valve Operation: Operate each valve in the system and observe its behavior. Some valves might be manual, requiring physical manipulation, while others could be automated or electronically controlled. If a valve is not responding as expected or feels stiff, it could be an indicator of a problem.
        • Pressure Testing: If you suspect a valve is failing but cannot visually identify the issue, consider performing a pressure test. Close off all valves except the one you suspect is faulty, and then increase the pressure within the system. Look for leaks or abnormal pressure drops. Keep safety precautions in mind while conducting pressure tests.
        • Inspect Valve Components: If you have access to the valve, inspect its components for signs of damage, wear, or corrosion. Check the valve’s handle, stem, and packing gland. If the valve is motor-operated, check the motor and associated wiring.
        • Keep Records: As you go through the process, make notes of your observations, tests conducted, and any changes made. This documentation can be valuable for future reference and maintenance.

 Replace damaged components and ensure all connections are secure. Remember that bilge systems can be intricate, and the location of a failed valve might not always be obvious. Patience, attention to detail, and a methodical approach are essential when troubleshooting valve failures in vessel bilge systems.

    • Routine Maintenance: Establish a regular maintenance schedule that includes cleaning, lubricating, and inspecting the bilge system components. This proactive approach can prevent many issues from arising in the first place.

In conclusion, the vessel’s bilge system is a vital component for ensuring the safety and operational efficiency of the vessel. Addressing problems within this system requires a systematic troubleshooting approach that involves careful inspection, testing, and maintenance. By understanding common issues such as clogs, pump failures, float switch malfunctions, leaks, electrical problems, and inadequate maintenance, vessel owners and engineers can take proactive measures to prevent and resolve these problems. Regular maintenance and prompt troubleshooting not only keep the bilge system in top condition but also contribute to the overall safety of the vessel and its crew.

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