SE25 Tunnel bow thruster, 12V

SE25 Tunnel bow thruster, 12V
25kg thrust On/Off

The world’s leading series of bow and stern thrusters for leisure boats are the SE series from Side-Power. Side-Power offers the world’s largest range of DC thruster systems for leisure boats. 

All the approved features and well-known quality boat builders around the world value, are now available for even smaller vessels.

With the new SE25, we add yet another tunnel diameter to our extensive program. With a tunnel diameter of only 110mm, the SE25 is suitable for vessels up to 24 feet depending of the vessels windage area. As with all the other thruster models in the SE series, the SE 25 also offers tremendous installation flexibility, as the thruster can be installed upon the tunnel in any angle and the thruster motor can be rotated on the motor bracket in 90 degrees steps. 

The SE25 are galvanic insulated as the larger thrusters in the SE series and features Side-Powers patented IPC technology for intelligent power control and safety. 

The SE25 is only available for bow installation.

Side-Power Intelligent Power Control

Intelligent Power Control

The Side Power unique thruster controller that intelligently protects the thruster from potential inherent problems in all high current applications as well as user faults. It includes several important safety features imperative in a product with such high power, run by DC electrics, as a thruster.

  • Provides delay between drive directions
  • Monitors solenoid functions to reduce the chance of solenoid lock-in
  • Will stop the thruster in case of a lockedin solenoid, without extra user action and even without controlling a main switch.

Side-Power Single Propeller

Single Propeller

A properly engineered single propeller system will be the most energy efficient thruster. Its compact design fits easily into narrow bows making it the perfect match for our smaller models. With more than 60.000 single propeller thrusters in use, the Sidepower single series system has proven its reliability.


Side-Power Sealed Drive

Sealed and lifetime lubricated gearleg

Sealed gearleg with long-life "mechanical" seal where highly polished ceramic and carbon surfaces form the only moving sealing surfaces, ensuring protection against damaging water intrusion into the gear leg. Pre-filled with special gear oil for lifetime lubrication.

  • "Mechanical" seals with surfaces of ceramic and carbon for ultimate security against water intrusion

Side-Power Galvanic Separation

Galvanic Separation

The gearhouse / drive legs of most Side-Power DC electric thrusters are now fully galvanically isolated / separated from the electric motor and motor bracket. This ensures that even if there is an accidental short circuit or a current leak for other reasons, the immersed parts are not effected as they could be with direct electric contact.

  • Achieved by composite bushings around the bolts and beneath the washers and a bushing in the motor bracket electrically isolating the drive housing from the motor bracket.
  • Available on DC electric models with flexible couplers only, where the flexible coupler provides galvanic separation of the motor and gearleg shaft.

Side-Power Q-prop™


The new 5 blade special skew propellers are the result of over 2 years of development work and thousands of tests. They have been designed to reduce the noise level, while maintaining the exceptional efficiency of the old 4 blade Side-Power propellers. This goal was achieved, and we even chose to make them a little bit more aggressive on some models, increasing the thrust on some thrusters about 5%. Please see individual information on each new thruster for more details.

  • Noise reductions of up to 75% measured in controlled environments
  • The expected and tested normal noise reduction in average installations: 20-40%
  • Will be delivered on all Side-Power models except models with 300 mm and 385 mm tunnel diameter
  • Upgrade kits are available for most SP series thrusters with special adaptors
Thrust at 10.5/21V* (kg • lbs) 25 • 55
Thrust at 12/24V* (kg • lbs) 30 • 66
Typical boat size (ft • m) > 24' • > 7.3
Tunnel I.D. (mm • in) 110 • 4.33"
Propulsion Single
Power at 10.5/21V* (kW • hp) 1.5 • 2
For DC system (V) 12
Weight (kg • lbs) 9.5 • 21
Min. Batt. Capacity (CCA** 12/24V) 200/380
Control system Analog

* All Side-Power thrusters gets their thrust rating from the actual performance you can expect in a boat - at the voltage a normal installation will provide at the thruster. We have choosen to use the net performance at 10.5V/21V, but we also list the effect at 12/24V for comparison.

** All battery CCA ratings are stated with the DIN rating, multiply by 1.9 to to get the SAE equivalent (at 0°F, ABYC standard)


Thruster (mm) A B C D E min F F recommended G min G max
SE25/110S 110 247 155 177 110 92 184 4 6
# Description Product
1 Motorbracket complete Ø110 SM-126302
1.3 DIN 912 - M8 x 30 6 1360
2 Gearleg u/propell 2 0600-U
2.20 Gasket 3 1310 10
2.21 DIN 985 - M8x1,25 3 1250
2.23 DIN 125 - A 8,4 208125
2.24 DIN 6912 - M6 x 30 110033
2.25 Anode Kit 3 1180 A
2.25.1 Anode 3 9998
2.25.2 DIN 912 - M5 x 12 3 1172
3 Propeller Ø107 2 1261
4 Electric motor 2 1012 K
5 Rele mounted SE20/25/30 -12V 41571122
5.1 Rele SE 30-12V 4 1571 12
5.2 Set skrue dekse 6 1287
5.3 Foring messing 10 1274
5.4 DIN 128 - A6 SM-136745
5.5 Solenoid bracket kit 2 0135
6 Plastic Nut 6 8810
8 Relay Cover 3 2024
9 ISO 8734 - 4 x 28 - A 112032
10 SE25 - 30 SM159145
10.1 Delay relay 6 1232 I
10.2 Internkobling SE30 6 1200 B
12 Coupling SM-125918
13 Brushes for motor ( kit ) **
14 Brushes spring for motor ( kit ) **
15 Temp switch **


13 Please provide thruster serial # when ordering product.
14 Please provide thruster serial # when ordering product.
15 Please provide thruster serial # when ordering product.

The installer alone has responsibility for the installation of the spare parts. Side-Power only warranty the spare parts supplied only.

The information given in the document was correct at the time it was published. However, Sleipner Motor AS can not accept liability for any inaccuracies or omissions it may contain. Continuous product improvement may change the product specifications without notice. Therefore, Sleipner Motor AS can not accept liability for any possible differences between product and document.

File Type Language Download
Product specification sheet SE25 EN.pdf Product sheet English  Download
Installation Manual, SE (20, 25, 30, 40).pdf Installation Manual English, Norwegian  Download
User Manual, SE and SE ignition protected (SE, SE-IP).pdf User Manual English  Download
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