Sleipner SE40 12 Volt Tunnel Stern Thruster Kit

Sleipner SE40 12 Volt Tunnel Stern Thruster Kit

Sleipner SE40 12 Volt Tunnel Stern Thruster Kit is a compact yet remarkably powerful solution, specifically designed to give you total control of your vessel’s aft. Built with Sleipner’s world-renowned Norwegian engineering, this 12-volt system delivers between 40kg and 48kg of thrust, making it the perfect partner for motorboats and yachts between 26ft and 34ft (8m – 10.5m).

What sets this kit apart is the Q-PROP™ 5-blade skew propeller. Unlike traditional thrusters that can be noisy and cavitation-heavy, the SE40 is designed for near-silent operation, reducing noise by up to 75% in controlled tests. It’s small enough to fit into tight bilge spaces but powerful enough to push your stern exactly where you need it, even when the British weather decides to play up.

Sleipner SE40 12 Volt Tunnel Stern Thruster Kit Key Features

• Intelligent Power Control (IPC): Safety is paramount. Sleipner’s patented IPC technology monitors solenoid functions and provides a delay between drive directions, significantly reducing mechanical wear and preventing accidental "lock-ins.
• "Q-PROP™ Quiet Technology: The 5-blade skew propeller doesn't just reduce noise; it increases efficiency, ensuring you get maximum push for every amp drawn from your battery.Flexible Installation: Space is often at a premium in the stern. The SE40’s motor can be rotated 90 degrees on its bracket, and the unit can be mounted at any angle on the tunnel to fit your specific hull configuration.
• Sealed-for-Life Gear Leg: The gear house is pre-filled with lifetime lubrication and features a high-grade mechanical seal (ceramic/carbon) to ensure water stays out and the oil stays in.
• Galvanic Separation: To protect your investment, the gear house is galvanically isolated from the motor and internal electrical system, preventing the stray current corrosion common in saltwater environments.
• Overheat Protection: An integrated thermal switch automatically shuts the unit down if it exceeds safe operating temperatures, protecting the motor from damage during extended use.

Technical Specifications:

• • Typical Boat Size26’ – 34’ (8m – 10.5m)
  • Thrust at 10.5V / 12V40kg / 48kg
  • Voltage12V
  • Power Output2.2 kW (3hp)
  • Tunnel Internal Diameter125mm
  • Weight10kg (Motor unit)
  • Min. Battery Capacity300 CCA (DIN) / 570 CCA (SAE)

Sleipner SE40 12 Volt Tunnel Stern Thruster Kit FAQs

Is the SE40 the right size for my boat?

The SE40 is specifically designed for boats between 26 and 34 feet (8m – 10.5m). It delivers a solid 40kg of thrust at 10.5V, and up to 48kg at a full 12V. If you’re at the upper end of that size range or frequently boat in high-wind areas, the SE40 provides that extra "bite" you need compared to the smaller SE30.

What actually comes in the "Morgan Marine Stern Kit"?

We’ve bundled this as a "ready-to-go" kit to ensure you aren’t hunting for parts mid-installation. It includes:

• • The SE40 Thruster Motor: The 12V power unit.
  • Stern Tunnel: A durable GRP (glass-reinforced plastic) housing designed for transom mounting.
  • Dual Joystick Controller: Allowing you to manage both a bow and stern thruster from one station.
  • Wiring Loom: A 7-metre plug-and-play cable (other lengths available on request).
  • Automatic Main Switch & Fuse: Essential safety components to protect your electrical system.

Can I install this thruster myself?

The SE40 features Sleipner’s Plug & Play wiring, which significantly simplifies the electrical side. However, installing a stern thruster requires drilling into the transom and ensuring a watertight, structural bond for the tunnel. If you aren’t comfortable with GRP work, our team here at Brightlingsea offers professional fitting services—just give us a bell for a quote.

I have a shallow draft; will the tunnel be deep enough?

Sleipner recommends a minimum water depth of 125mm from the waterline to the top of the tunnel. If your boat’s configuration means the tunnel sits higher than this, we can supply optional cowls (spoilers) that prevent the thruster from sucking in air (cavitation), ensuring you don’t lose power.

How noisy is it? Will it wake up the whole marina?

Sleipner is famous for the Q-PROP™ 5-bladed skew propeller. This isn't your standard noisy thruster; the design reduces noise by up to 75% in controlled tests (typically 20-40% in real-world conditions) while actually increasing efficiency.

What are the battery requirements?

To get the full 48kg of thrust, you need a healthy battery bank. The SE40 requires a minimum of 300 CCA (DIN). We always recommend keeping your engine running while using the thruster to maintain voltage and ensure peak performance.

Does it have any safety cut-outs?

Yes, it’s remarkably "intelligent." It features:

• • Intelligent Power Control (IPC): Protects against solenoid "lock-in" and includes a delay when switching directions to protect the gear leg.
  • Overheat Protection: An internal thermal switch will automatically shut the motor down if it gets too hot (usually after about 3 minutes of continuous use), resetting once it cools.

How do I maintain it?

Maintenance is straightforward. The gear leg is sealed for life, so there’s no oil to change. You’ll just need to check the zinc anodes annually (which we stock here at Morgan Marine) and keep the propeller free of growth.

Is it protected against corrosion?

Absolutely. The SE40 features Galvanic Isolation, meaning the gear leg is electrically insulated from the motor. This is crucial for preventing stray current from eating away at your thruster components while sitting in the salt water.

Can I use this with my existing bow thruster?

Yes! The dual controller included in our kit is designed to work alongside your current bow thruster, giving you "sideways" control of the entire boat. If you have an older system, our technical team can advise on compatibility.