Thrusterpedia

Which boat thruster, what it costs, how to get it installed

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Drawing of a tunnel thruster: a tube through the bow below the waterline, the hull cut away to show the motor on top.
Our drawing of a tunnel thruster, the same for every maker. It is not Sleipner’s own design.

Sleipner · tunnel thruster · bow or stern

Sleipner SAC1100: specs, price and the boats it fits

It gives 2425 lb (1100 kgf) of push. Sleipner sells it for boats of 105 to 160 ft.

The unit$48,000Equipment only, Imtra, read 26 October 2026
Installed by a yard, 135 ft boat$56,719 to $69,240Our estimate: the unit, labor, haul-out, battery and parts
  • Haul-out to install
  • DIY 2 of 5: wiring prep only
  • 2-year warranty

Quick stats

  • Thrust 2425 lb 1100 kgf, Sleipner's rating
  • Boat length 105 to 160 ft Sleipner's own range
  • Price per lb of thrust $19.79 Unit only. $23 to $29 installed
  • Voltage Not stated Ask the maker before wiring
  • Battery Not published Ask the maker before wiring
  • Run limit Not published Ask the maker before long use
  • To install it Haul-out The boat comes out of the water
  • Mounts Tunnel Fixed mount, bow or stern

About the Sleipner SAC1100

The SAC1100 gives 2425 lb of push from a 513 mm tunnel, for yachts of about 105 to 160 ft, and is the largest AC tunnel Imtra lists. It needs a 380 to 440 V three-phase supply.

Imtra lists the horizontal build at $48,000, before a separate tariff line. The manual gives a maximum draw of 134 A at 400 V and a generator load of 81 kVA. See the specs.

Read more

This C build is rated continuous at 1,100 kg. Sleipner also makes an I build of the same size that holds 900 kg continuously and peaks at 1,100. Warranty: two years.

Installers will find the wiring figures and dimensions further down. For the rest of Sleipner’s line, read the Sleipner (Side-Power) review.

Sleipner sold its thrusters under the Side-Power name until 2021, and many dealers and owners still call them that. It is the same company and the same thrusters.

Where this summary comes from (5 sources, read 15 October 2026)

Will the Sleipner SAC1100 steer your boat?

23 FT TRAWLER · BOW · 15 KT WIND

Size forThis page always opens on Steering.

Every knot figure here is wind speed, not boat speed or current.

Steers her at 125 kt

On a 23 ft trawler the Sleipner SAC1100 (2425 lb) steers her in a 125 knot breeze. Her bow needs about 35 lb from a tunnel to steer her in a 15 knot breeze.

The finder leaves it off her list. Sleipner lists it for 105 to 160 ft.

8 FT LEVER Sleipner SAC1100 pivot

A tunnel at the bow of a 23 ft trawler 35 lb ★ this unit · 1 to 3: the three cheapest others that steer her at 13 kt or more, installed

  1. ★ Sleipner SAC1100 this unit 2425 lb · tunnel from $54,719 Steers her at 125 kt
  2. 1 Lewmar 110TT Thruster Kit 62 lb · tunnel from $7,383 Steers her at 20 kt
  3. 2 Lewmar 110TT 1.5 Bow Thruster Complete Package 62 lb · tunnel from $7,402 Steers her at 20 kt
  4. 3 VETUS Bow 25 55 lb · tunnel from $7,889 Steers her at 19 kt

The Sleipner SAC1100 on a trawler, by length

  1. 25 ft113 kt
  2. 30 ft95 kt
  3. 35 ft81 kt
  4. 40 ft72 kt
  5. 45 ft64 kt
  6. 50 ft57 kt
  7. 55 ft52 kt
  8. 60 ft48 kt
  9. 65 ft44 kt
  10. 70 ft41 kt
  11. 75 ft38 kt
  12. 80 ft36 kt

Outlined: the finder does not list it at that length (under 13 kt, far more than she needs, or outside Sleipner’s own length range).

  • Under 10 kt
  • 10 to 15 kt
  • 15 to 20 kt: the sweet spot
  • Over 20 kt: more than she needs

Prices are the low end of the installed total, from our estimate. For your own boat, drive and installer, the finder prices each unit.

Is it right for your boat?

What Sleipner says 105 to 160 ft The maker's own range, from its listing
What our sizing says No fit found On no boat type at any length
Every kind of boat it fits, by length ten boat types
Which boats it fits, by length
Boat Full thrust at 15 knotsStill a fit, in lighter wind
Pontoon & tritoon Not listed. A pontoon has no hull body between the logs to bore a tunnel through, and nobody sells one for these boats.
Sailboat No length. More thrust than the boat needs.
Houseboat No length. More thrust than the boat needs.
Catamaran No length. More thrust than the boat needs.
Trawler No length. More thrust than the boat needs.
Motor yacht No length. More thrust than the boat needs.
Bass & flats Not listed. Nobody sells a tunnel kit for these hulls, and a bass boat’s shallow planing bow has almost no depth to hold one.
Wake & ski boats Not listed. Nobody sells a tunnel kit for these hulls.
Express cruiser No length. More thrust than the boat needs.
Center console No length. More thrust than the boat needs.

The Sleipner SAC1100 against each kind of boat, in a 15 knot wind. Our sizing, from the finder’s own rules.

The first column is where one unit gives all the thrust the boat needs in 15 knots. The second is where the finder still lists it: the unit steers her in a 13 or 14 knot wind, within 15 percent of the 15 knot breeze this site sizes for. On a boat shorter than the first column’s shortest length, the unit is more than the boat needs.

How we size it

Our figure is the longest boat one unit can steer in a 15 knot wind. It is a range because each kind of boat catches the wind differently. The maker gives one range for every boat.

The table tries the Sleipner SAC1100 on each kind of boat, at every length that kind of boat is built in. The wind is 15 knots and the rules are the finder’s own. A length counts as a fit when the unit gives the thrust that boat needs at the bow and the maker lists it for that length.

A boat up to 10 percent past the maker’s range still counts here, as it does in the finder.

No boat type and length in the table is a fit. For your own boat, the finder gives an answer that also counts your drive and who does the installing. The compare page sets this unit beside others.

What it costs installed

A yard job, everything in. Our estimate.

Installed by a yard
Boat Total installed
105 ft $56,219 to $67,800$23 to $28 a lb of thrust
135 ft $56,719 to $69,240$23 to $29 a lb of thrust
160 ft $57,139 to $70,450$24 to $29 a lb of thrust

From the shortest to the longest boat it is sized for.

What is in each total five lines

These totals are our estimate of a yard job: the unit’s price, plus a yard’s hours at $160 to $180 an hour, plus the batteries, cable and charger, plus the other parts the box does not hold. A Lifting the boat out of the water on a travel lift or a trailer so work can be done below the waterline. It is billed separately from the job itself. adds $1,910 to $7,720 at these lengths, with 5 to 7 days out of the water, worked from eight yards’ own rate cards. The hours come from what owners and yards report. The cost page builds the same figures line by line.

Each line of the estimate
Boat length The unit Yard labor Haul-out Batteries, cable, charger Other parts
105 ft $48,000 $5,120 to $12,60032 to 70 hours $1,910 to $5,070 None $1,189 to $2,130
135 ft $48,000 $5,120 to $12,60032 to 70 hours $2,410 to $6,510 None $1,189 to $2,130
160 ft $48,000 $5,120 to $12,60032 to 70 hours $2,830 to $7,720 None $1,189 to $2,130

For every length in the table above.

The sizing and the costs on this page are estimates, for guidance only and without warranty. They are no quote, and nobody has inspected your boat. Check them against the maker’s manual and your yard before you rely on them. Terms of use.

DIY breakdown

DIY 2 of 5: Wiring prep only. The yard installs the unit and does the hull work; you do the wiring prep.

DIY levels

  • Level 5: Owner install. No yard, no electrician.
  • Level 4: You install it, electrician connects. You mount and wire it; a marine electrician makes the final connections.
  • Level 3: Split with the yard. The yard does the below-waterline part; you do the wiring.
  • Level 2: Wiring prep only. The yard installs the unit and does the hull work; you do the wiring prep.
  • Level 1: Yard job. A qualified professional does all of it.

You Yard Electrician. The bar is labor hours; a haul-out is a note.

How we rate DIY

You: 4 to 16 hours Yard: 32 to 70 hours Electrician: 2 to 4 hours Plus a haul-out.

Your part needs:Heavy battery cableCrimping big lugs

Every step, and who does it three steps
  1. Cut, bond and fair the tunnel; fit the gear leg, motor and propeller Yard 32 to 70 hours The low end is two crew over two days, the job as owners describe it on the forums. The high end rises with boat length between two real billed figures: 32 hours at 35 ft, and the largest invoice we hold, 70 hours at 47 ft.
  2. Mount the battery box, switch and fuse holder; run and secure the cables You 4 to 16 hours Our estimate. No maker times this step, and a first-time owner is slower than a yard, so the range is wide.
  3. Final connections at the battery and the motor, load test Electrician 2 to 4 hours Our estimate. Nobody publishes a time for the final connections and test on their own.

A qualified marine electrician should make the final connections and test them before first use. Hours are labor only.

Related videos

Two of Sleipner’s own videos, from its YouTube channel. They play only when you tap. A maker’s video is its pitch, so take any claim back to the figures on this page.

Sleipner / Side-Power thruster systems - the importance of correct tunnel installation!Maker Sleipner’s own channel
eVision: Sleipner e-series thrustersMaker Sleipner’s own channel

Know before you buy

What sets this model apart, what it costs to keep, and what to weigh.

Price per pound of thrust

$19.79 a lb The unit’s price over its published thrust. The bars are Sleipner’s next sizes and the nearest other makers.

Controls

Gasket, bolts and anode with the unit. The panel, its cable, the fuse and main switch are bought.

Service and warranty

Sleipner gives 2 years for leisure use and 1 for commercial use. It transfers to the next owner, and it starts no later than 18 months after the boat's first launch.

See Sleipner’s warranty Sleipner's warranty statement, effective 1 April 2022.

Special mentions

Sleipner sells it for either end, so it can go at the bow or the stern.

Dealer prices at Fisheries Supply, read 26 October 2026.

What to weigh

The boat comes out of the water to install it: it needs a tunnel bore below the waterline.

Parts for the Sleipner SAC1100

See the Sleipner SAC1100 manual

Search for the number as printed here, with no spaces. Prices are each dealer’s on the day shown, before shipping and tax. Check the plate on your motor before you order: some parts change with the tunnel size, the voltage or the year.

For the install what the box leaves you to buy

the box

The manual button above opens it on the maker's product page. It has the hull, wiring and fuse figures for this model.

From Sleipner’s SAC750 to SAC1400 installation guide, document 6002 rev 21, 2025, read 25 October 2026.

In the box
The guide prints no box list. It has you install the unit with the gasket and the bolts provided.
Bought separately
The control panel with its own guide, the S-Link cables, the tunnel and the AC power supply. The guide says the AC units run on standard variable frequency drives.
Charging
It runs on the boat's AC power, so there is no thruster battery to charge. The S-Link controls run on the boat's DC supply.

The “other parts” line in the estimate above covers these parts as a range, $1,189 to $2,130 at Fisheries Supply’s prices on 30 September 2026 and 26 October 2026, because the exact items depend on your boat. It runs on AC power, so there is no battery, charger or battery cable to buy. The cost page has what every maker says about each part.

Other sizes and close alternatives

The other makers listed are the nearest match each makes, of the same style and for the same end, within a quarter of its thrust. The compare page lists every model, and the thruster index lists every model with a page here.

For the yard and the installer

Every published figure, with its source.

Full spec sheet thrust, motor, mounting, price, part number, documents
Full spec sheet
Thrust and motor
Thrust 2425 lb (1100 kgf) As printed: Thrust, continuous 1100 kg
Motor70 kW
VoltageNot stated
Run limitNot published
Installation
TypeTunnel, fixed mount
End of the boatBow or stern
Tunnel diameter513 mm
What it does to the hullTunnel bore below the waterline
Haul-out to install itYes
Maker’s boat length105 to 160 ft
Price and ordering
Price $48,000 equipment only, a dealer's price, imtra.com, 26 October 2026
Part number SAC1100/513-C4H380-440 V AC 3-phase
Documents
Manual Installation manualon the maker's product page
The site’s reviewSleipner (Side-Power) review

Every published figure the site holds for the Sleipner SAC1100, with where each came from.

The tunnel: length and depth rules

Tunnel length. Avoid a tunnel longer than four times its diameter. Friction inside a long tube slows the water and cuts thrust. Too short, and the flow reaches the propeller before it has straightened, which the manual says causes cavitation and noise. The propeller must sit entirely inside the tube. Sleipner’s installation manual.

Depth below the waterline. As deep as possible under the waterline, and as far forward as possible. The depth for a given model is in that model’s own measurements. Deeper prevents air being sucked in from the surface and raises the water pressure at the propeller. SE20 to SE40 installation guide, 5611 rev 25 (2025).

Our notes from the manual and listings

In the box: Gasket, bolts and anode with the unit. The panel, its cable, the fuse and main switch are bought.

Our note

It runs on three-phase AC from the boat's generator through a speed controller (VFD), not on a battery bank. This build is for 380 to 440 V, mounted horizontal.

Where each point above comes from
  • Sleipner sells it for either end, so it can go at the bow or the stern.The maker's listing
  • The boat comes out of the water to install it: it needs a tunnel bore below the waterline.The mounting: a bore through the hull, or a housing recessed into it

Not sure this is the one? The thruster finder asks about your boat and prices every unit that fits.

Where to go next

The specs are the maker’s and the dealers’, on the dates shown. The sizing and the costs are our arithmetic, done without seeing your boat.