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What is the Smallest Bilge Pump I Need?

What is the Smallest Bilge Pump I Need?

Although the idea of the bilge pump dates back to the Romans, the first bilge pump as we know it was invented in the mid-1800s. Whether you’re using a recreational boat or a large marine vessel, a bilge pump is a must and will guarantee that your boat will be safe to use.

The bilge is the shallow part at the bottom of the hull, and it’s quite natural for water to collect there. But when the water stays for too long, your boat will become unstable and unsafe, and there’s even a risk of your boat sinking.

What is the smallest bilge pump you can install on your boat? What is the right bilge pump for your vessel? Keep on reading to learn more about this topic. Here’s a popular small pump for reference:

What is the Smallest Bilge Pump You Need?

If you’re a new boater, you might be asking yourself if you’ve picked the right bilge pump for your vessel. The pump has a crucial job: to remove the water that collects in the bottom of the hull for several reasons.

  • This water can collect after regular cleaning activities.
  • Rainwater can collect in the hull.
  • Spray water from the waves while the boat is moving can accumulate.
  • In-coolers and drainage systems on the boat can make the water accumulate in the hull.
  • A minor leak can also lead to the accumulation of water.

The size of the pump should be related to the overall size of the boat to guarantee that it’s able to get rid of water efficiently. On boats, small plastic pumps will work well to keep your boat dry. There are even some manual models if you’re driving a small recreational boat. Big marine ships have sturdy pumps that are usually made of cast iron to be able to remove the water promptly.

How Small Can My Bilge Pump Be?

If you have a small boat, then you can think about a centrifugal or diaphragm pump. The size of the pump is related to the size of the boat.

For an 18-foot boat, you need a pump with an output between 300 and 500 gallons per hour. For a 20 to 26-foot boat, you need a pump with an output between 600 and 1200 gallons per hour.

What Are the Benefits of Using a Bilge Pump?

Since humans discovered a safe way to travel on water, inventing a machine that gets rid of the accumulated water became a must. So here are some benefits of having a bilge pump on your boat.

  • Installing a bilge pump is a legal requirement. This means that you can’t take your boat to the water unless you have a functional pump installed, or you will get into legal issues. Maritime law determines that the number of pumps installed on the vessel and their power should be directly proportional to the size of the vessel and the number of passengers.
  • A bilge pump guarantees that water will be removed as soon as possible to prevent overflooding the engine room. It also maintains the balance of the boat as the accumulated water can fill one of the compartments, especially in recreational boats because they don’t have deep bilge wells.
  • Most pumps come with a unique automatic switch that activates them with no input from the boater. This is a big plus, especially for beginner boaters, as the pump automatically operates whenever the water exceeds a certain level. As a result, you, as a boater, won’t have to worry about activating the bilge pump, and you can enjoy maneuvering your boat and exploring the water.
  • Depending on the size of the boat and the power of the pump, it can help save your boat from sinking if there’s a small hole. Although a hole will cause the water to get inside the boat, the pump will get rid of it faster than it collects. So even if the pump can’t remove all the water, it will at least give you time until help arrives.

Different Types of Bilge Pumps

There are four different types of pumps that you can consider, and each one of them will work for a specific boating situation.

Centrifugal Bilge Pumps

These are the most common types because they’re simple to use and more affordable. These pumps are also easy to maintain and can handle debris. However, before using a centrifugal bilge pump, you need to fill it with water first or prime it.

It features a motor that drives the impeller to push the incoming water to the casing sides. The volute casing has a tapered design that gets wider towards the discharge. The water leaves the discharge and creates low pressure to drive more water outside. Unfortunately, this pump is unable to remove all the water, and there’s always a need for another pump to force more water outside.

Diaphragm Bilge Pumps

If you have a small or medium-sized boat, then this type will work for you. A diaphragm bilge pump doesn’t need priming and can remove all the water. The diaphragm pulls up and creates a vacuum that sucks water. However, this pump will also suck air, so you don’t have to place it too close to the bilge.

Some of these pumps are also manual, so they will be more affordable. However, these pumps have lower capacities and don’t handle debris.

Reciprocating Bilge Pumps

These pumps can pump vertically and don’t need priming. Unlike other pumps, these ones can also handle viscous liquids, so they’re usually used by large ships to remove sludge.

Some of the reciprocating bilge pumps are manual, and they’re designed to remove all the water from the bilge wells. However, they have lower capacities and can’t handle any debris.

Flexible Impeller Pumps

Flexible impeller pumps use a squeezed and curved rubber impeller. They’re designed to remove all the water and are also able to handle debris.

However, you shouldn’t use a flexible impeller pump when it’s dry, as the friction between the casing and the impeller can burn the rubber. These pumps are affordable, but they have lower capacities.

Wrap Up

Regardless of the size of your boat, you need a bilge pump to remove the excess water and keep your boat safe and dry. There are different types of pumps on the market, and some of them are designed for large vessels, while the others will work for a small recreational boat.

Regardless of the type you choose, you need to pick a pump designed to remove water efficiently and quickly to keep your boat afloat and protect the engine room from damage.