Most boats tend to use a system to remove water from their hull, and that system is called a bilge pump.
Most bilge pumps come on automatically, with many having the option to manually turn them on. No boat is a perfect seal, so having bilge pumps to suck out the water is a good idea.
Since a jet ski is a type of boat, many wonder if they come with some kind of system to remove water, too?
Let’s talk about that and how uncommon it is.
Do jet skis have bilge pumps?
It’s common for a jet ski to NOT have a bilge pump. I say most, as a few will come with a bilge pump, but it’s not the norm.
Instead, jet skis have bailer tubes.
Bailer tubes work similarly, it sucks extra bilge water out of your hull, but the difference is that bailer tubes only work when the engine is on.
Bilge pumps run off electricity and gets that power from the battery. So long as the battery in your boat is good, your bilge pump will suck out any extra water.
Jet skis, on the other hand, have bailer tubes, and they work off the vacuum suction that is created by the jet pump to suck out any water in your bilge. So you must have the engine running to have the bailer tubes work.
How Bailer Tubes Work On a jet ski
Bailer tubes are simpler than a bilge pump, it’s literally only tubes.
The jet pump has one or two tubes that stick out and run into the hull. These tubes curve upward and then back down, which helps prevent water from coming in. They also have one-way check valves for extra protection.
When the engine is running, the impeller inside the jet pump spins and pushes water out through the nozzle. Just above the nozzle are the bailer tubes. As water rushes past these tubes, it creates suction that pulls any water out of the hull.
When you turn the engine off, the impeller stops spinning, so no more water gets sucked out.
If your jet skis start taking on water, start moving right away and head for land. The suction from the pump is what keeps your hull from filling up, it’s your only way to stay afloat.
Can you add a bilge pump?
You can add a bilge pump to a jet ski, and many manufacturers even sell OEM kits to make installation easier. There are also aftermarket and third-party options that work just as well—as long as your battery is charged.
Most bilge pump kits require drilling a hole in the fiberglass hull so the water can drain out. If drilling into the hull makes you uncomfortable, it’s a good idea to let a jet ski dealership handle the installation.
OEM kits often use an automatic float switch that turns the pump on when enough water builds up. Some kits are less ideal—they run constantly whenever the key is on, acting more like a second bailer system than a true bilge pump.
I’ve installed several Sea-Doo kits myself. It’s not difficult, just a bit tedious. You’ll need to tap into the fuse box and drill into the side of the jet ski. If you’re comfortable with basic wiring and don’t mind taking your time, most people can do it themselves.
The hardest part is mounting the pump to the bottom of the hull. Some pumps need to be glued down with epoxy or attached using a special bracket. Some jet ski models have a built-in spot for an OEM pump, but that only works with their brand. Third-party pumps that move more water (higher GPH) and run automatically may need more planning, but they’re worth the effort if installed correctly.
Do You Need a Bilge Pump?
Whether you need a bilge pump depends on how and where you ride your jet ski.
If you ride hard or in rough water, have marine bilge pumps is a smart choice. Also, if your jet ski sits on a lift, and you don’t remove the drain plug, it’s a good idea to install an automatic bilge pump and keep the battery charged.
A bilge siphon system is not foolproof and not meant to be a solution that allows you to keep your jet ski in the water all the time. Their batteries are small and a pump running all the time will drain it, getting a solar charger can help, but still, it’s not perfect.
If you’re buying a new jet ski, consider making it a part of the deal. It’s better to get the dealership to install one before you take delivery, as it’s one less thing to worry about.
Why are bilge pumps not standard?
Bilge pumps have not been a standard on PWCs because they’re are more enclosed than boats.
Boats are like big open tubs, their decks drain directly into the bilge. So when a boat takes on water from waves or rain, it all ends up in the bottom of the hull. That’s why boats need electric bilge pumps to remove the water and prevent sinking.
A jet ski is more of a closed system. While it’s not completely sealed, it’s much less open than a boat.
Jet ski manufacturers also don’t expect you to leave them in the water for long periods like you would with a boat. They assume you’ll store it on a trailer or a drive-up lift—just like it says in the owner’s manual.
However, that could change. Today’s jet skis are much larger than they were 20 years ago. With more space inside, it would make sense for manufacturers to start including bilge pumps as a standard feature.
Bilge pumps are not perfect!
A bilge pump can help keep your jet ski from sinking from small leaks, but they’re not a fix for everything.
A common myth is that an electric bilge pump will guarantee your jet ski won’t sink. That’s not true. If there’s a big leak, the pump might not keep up.
I’ve seen jet skis with fist-sized holes in the hull, and even with a pump running, they still sank. Add in the fact that jet skis have small batteries, and it’s clear these pump systems have limits.
That said, it’s still better to have a bilge pump on your skis than not, it could make all the difference in an emergency.
Also, if anyone is wondering, jet skis won’t completely sink. If you look in the hull, you’ll see a bunch of foam. That foam does only one purpose, if it completely takes on water, that is what keeps it from sinking to the bottom of the lake or ocean. The foam is located at the nose and midsection, so if it sinks, the nose will float. But once on land, you’ll need a water pump or to pull the drain plug to get the water out.
As usual, another great, informative article. Thank you, Steven!