How To Install Bilge Pump Alarm On A Boat


The majority of boats feature through-hulls, an inboard engine, and other ways through which water can enter. If your boat hull has a serious issue or one of the boat’s systems fails, water could overwhelm your boat’s bilge pump. In extreme instances, the water could sink your boat.

Installing a bilge alarm, bilge pump counter, or a bilge high water alarm can help you improve boating safety. The bilge alarm will help you correct a leak before the water obscures visibility in all areas. To help you keep your boat safe, we will show you how to install a bilge alarm.

Install the Bilge Pump First

If you just purchased your pontoon boat, the boat may not have a bilge pump. All boat types should benefit from an automatic bilge pump that turns on when the external or internal float sensor indicates that the water level has risen to a particular level in the bilge.

On most boats, the bilge pump installation involves wiring the pump into the electrical control panel. This usually tempts the boat owner to shut it off when leaving the boat’s steering wheel. In some instances, when the switch is left on, the power may be cut off if the marine battery gets switched off when leaving the boat. This generally defeats the whole purpose of the automatic pump.

To ensure that the automatic bilge pump does its job, you should consider wiring the pump directly to the batteries using an inline fuse. If you do this, the pump should run as long as the boat’s battery has power.

Since the pump could end up draining the battery completely, you should consider investing in multiple batteries. If you connect the batteries in parallel to the pump, you should reduce the risk of the batteries running out of power.

A Step by Step Guide on How to Install Bilge Alarm

If you have a bilge alarm wiring diagram, installing the bilge alarm should be relatively easy for you. One thing you will learn from the bilge alarm wiring diagram is that the bilge alarm wiring can be done alongside the bilge pump wires.

If you decide to purchase an already prepared bilge alarm, the alarm should feature the manufacturer’s proposed bilge alarm wiring diagram and the installation instructions. To succeed at installing the bilge alarm, you should follow the manufacturer’s instructions strictly.

In this section, we will be helping you build your own bilge alarm. To build the bilge alarm, you will need to invest in a 12-volt siren or buzzer, in-line fuse holder, crimp connectors, and hookup wire. If you already have these things, follow the steps below to install the bilge alarm:

Step 1: Install the float switch on your boat. You should locate the switch on the lowest part of your boat. Since you want the switch to activate when the amount of water coming aboard is more than the pump’s discharge capacity (or if the pump fails to run), you should locate the float switch higher than your boat’s bilge pump.

Step 2: Locate the siren or buzzer near the boat’s helm. This will improve your chances of hearing the siren over the other external noise. If you have boarded a boat in the past, after putting on your boat shoes, you already know that the external noises can be high.

Step 3: Remove the fuse from its holder. Next, crimp an appropriate terminal to one of the fuses’ leads and connect that to the battery’s positive terminal or a different 12-volt terminal that stays energized at all times.

The fuse helps eliminate any fire risk that could occur in the case of short-circuiting. It is supposed to be as close to the power source as possible. If you fail to use fuses on a boat featuring a fuel tank, you could be risking losing your boat in a fire.

Step 4: With the boat’s fuse still removed, make use of a crim butt-splice connector to connect the second holder lead to the hookup wire. After routing the wire to the already mounted float switch, ensure you cut it to length, and then connect it to one of the leads going to the switch using a butt-splice connector.

With the same wire length and 2 connectors, connect the lead of the switch to one of the leads originating from the buzzer. Connect the second buzzer lead to the battery’s ground terminal.

Step 5: Re-install your fuse.

Step 6: Test your circuit manually to make sure that it is working perfectly. To do this, lift the float switch manually.

To make sure that the switch connections stay dry, you should mount them higher than the switch itself. Additionally, you should secure the switch connections using heat-shrink connectors and cover them with a marine sealant.

Since the float switch will remain dry unless the water rises above the expected levels, this bilge alarm is supposed to work reliably with minimal attention. However, it is good practice to test the bilge alarm periodically by lifting the float, just to make sure that it is working normally.

Optional – Add a Switch to Turn the Alarm Off

If you install the bilge alarm correctly, it will do a good job of alerting you about leakages. When you are trying to locate and fix the leakage, however, you would want the alarm to remain off. Installing a switch in line with the bilge alarm can help you turn it off if the bilge pump does come on when you are trying to fix the leak.

Globo Surf Overview

If you are yet to install a bilge alarm on your sailboat, you could be compromising your sailing safety. Without the alarm, you may not have the ability to discover a water leak until it is too late.

Installing the bilge alarm is not too complicated. In this article, we have shown you how to assemble an effective bilge alarm. If you prefer purchasing a manufactured bilge alarm, you should use the manufacturer’s bilge alarm wiring diagram to install the alarm correctly.

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Globo Surf
My name is David Hamburg. I am an avid water sports fan who enjoys paddle boarding, surfing, scuba diving, and kite surfing. Anything with a board or chance I can get in the water I love! I am such a big fan I decided to start this website to review all my favorite products and some others. Hope you enjoy!