Boat Thruster Guide

What to buy, what it costs, what it takes to fit

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Thruster specs

Sideshift HB340: specs, price and the boats it fits

The HB340 gives a houseboat up to 40 ft a push at the bow or the stern when you dock. It bolts under the deck, drops into the water on a helm switch and stops at its working depth, so nothing goes through the hull. It has two propellers on 12 V. Sideshift has been selling deck-mounted retracting units for houseboats since at least 2006. It costs $5,995.

Your deck height decides one extra cost. The unit fits decks up to 24 in above the water, and between 24 and 30 in you’ll need Sideshift’s lowering kit for another $495. The batteries are yours to supply too: two starting batteries wired together, with cable and a charger, about $980 to $1,067 more. See what else the box leaves out.

Raise it before the boat passes 3 mph. Over the years, the shaft seal is the part to plan for, since owners of Sideshift’s other units report seals failing at seven or eight years. Use it in bursts of 3 to 5 seconds, never longer than 20 to 30. A replacement motor is $1,495, and the warranty covers parts for two years.

Fitting it yourself? The installer section has every spec, and the Sideshift thruster review sets this model against the rest of the Sideshift range.

Where this summary comes from (8 sources, read 11 October 2026)

Key facts

  • DIY level 4 of 5 You fit it, electrician connects
  • Thrust Not published Our sizing works from the motor's rating
  • Boat length Up to 40 ft Sideshift's own range
  • Price $5,995 full kit, sideshift.com, 30 August 2026
  • Fitted by a yard $7,623 to $9,954 Our estimate at 30 to 44 ft, unit and job
  • Voltage 12 V As sold
  • Mounts External Drops down, bow or stern
  • To fit it Afloat The maker says it goes on in the water
  • Run limit Bursts of 3 to 5 seconds Never more than 20 to 30 seconds at a time

Every figure here is the maker’s or a dealer’s, except the fitted cost, which is our estimate. The full spec sheet is further down.

How much of the install is yours

DIY 4 of 5: You fit it, electrician connects. You mount and wire it; a marine electrician makes the final connections.

DIY levels

  • Level 5: Owner install. No yard, no electrician.
  • Level 4: You fit 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 fits 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: 6 to 8 h Yard: none Electrician: 2 to 4 h No haul-out.

  1. Mount the thruster; fit the battery, controller and joystick; run the cables You 6 to 8 h Sideshift’s own figure: 6 to 8 hours per thruster, depending on the wire runs. Every mount and connection is above the waterline. Source.
  2. Final connections at the battery and the motor, load test Electrician 2 to 4 h Our estimate. Nobody publishes a time for the final connections and test on their own.

Your part needs:Drilling above the waterlineHeavy battery cableCrimping big lugs

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

Is it right for your boat?

What Sideshift says Up to 40 ft The maker's own range, from its listing
What our sizing says 30 to 44 ft On our estimate from the motor, across the kinds of boat it fits

Sideshift prints no thrust, so our sizing uses an estimate from the motor’s rating. That estimate can say a boat is too big for it. It cannot promise a fit. The maker gives one range for every boat.

The table below tries the Sideshift HB340 Retractable Houseboat Thruster 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 where it mounts 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. So the table runs up to 44 ft, just past Sideshift’s own range (up to 40 ft).

The Sideshift HB340 Retractable Houseboat Thruster against each kind of boat, in a 15 knot wind. Our sizing, from the finder’s own rules.
Boat Lengths it fits, on our estimate
Pontoon & tritoon Not listed. Its maker sells it for another kind of boat.
Sailboat Not listed. Its maker sells it for another kind of boat.
Houseboat 30 to 44 ft
Catamaran Not listed. An external unit bolts to the side of a single hull at the bow or to its transom, and a cat has two narrow hulls with a bridgedeck between them, so there is nowhere forward to hang one.
Trawler Not listed. Its maker sells it for another kind of boat.
Motor yacht Not listed. Its maker sells it for another kind of boat.
Bass & flats Not listed. This site lists no external bow unit for a boat that planes.
Wake & ski boats Not listed. This site lists no external bow unit for a boat that planes.
Express cruiser Not listed. This site lists no external bow unit for a boat that planes.
Center console Not listed. This site lists no external bow unit for a boat that planes.

It is sized for one kind of boat here. For your own boat, the finder gives an answer that also counts your drive and who does the fitting. The compare page sets this unit beside others.

What it costs fitted

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. The hours come from what owners and yards report. Your own yard will have its own opinion. The cost page builds the same figures line by line.

  • The unit$5,995
  • Yard labor$640 to $2,8804 to 16 hours
  • Batteries, cable, charger$980 to $1,067
  • Other parts$8 to $12
  • Total, 30 to 44 ft$7,623 to $9,954Our estimate

The Sideshift HB340 Retractable Houseboat Thruster fitted by a yard. It comes to the same at every length it is sized for. Our estimate.

How the batteries, cable and charger add up. We price a battery bank close to the thruster, as the makers recommend, with 10 to 20 ft of cable out and back: red for the positive, black for the negative, cut to length. The low end is the cheapest battery that meets the figure and the shorter run; the high end is a sealed (AGM) battery and the longer run. The charger is a NOCO GEN5X2 two-bank shore charger.

Batteries and lugs are priced at Fisheries Supply and the cable and charger at Defender, read 12 October 2026.

  • At 12 V: two 12 V batteries side by side (in parallel), at least 850 CCA each (Sideshift’s minimum), $720 for both; Sideshift’s cable table gives 2/0 AWG: $114 to $201 for the red and black cable and the lugs; a GEN5X2 charger, $146.

Fitting it yourself. Tell the finder you will fit a Sideshift yourself and it takes the yard’s labor off. With that off, the total is $6,983 to $7,074. That is the unit plus the batteries, cable and other parts, which you buy whoever does the fitting.

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.

What else you buy

What follows comes from Sideshift’s Monohull installation manual Rev 3.1, November 2025, read 30 September 2026.

In the box
The thruster, the motor controller, the wireless joystick and its receiver, a wireless key fob, the wiring harness and mounting hardware, the fuse in a holder with a digital voltage display, and a battery switch. Sideshift lists these on each product page. The manual adds the crimper, anti-seize, Loctite, Sikaflex and heat shrink.
Bought separately
The batteries, the 1/0 or 2/0 battery cable and the charger. The joystick is wireless: no wire runs from it to the thruster. It still needs 12 V at the helm for its own power, so plan a small feed there.
Charging
The thruster gets a bank of its own: cranking type, 850 cold cranking amps per battery, within 10 ft of the controller. You buy the charger too, either a shore charger or a DC-to-DC charger fed off the bank the alternator charges.

The manual’s words, page 40: “The 2 most popular ways are: AC/DC multi-bank charger such as the NOCO GEN5X2 (available in our online store). ... Using a DC-DC Isolated Charger such as the Victron Orion-Tr DC-DC Converters Isolated.”

The “other parts” line in the estimate above is the priced parts below, $8 to $12 at Fisheries Supply’s prices on 30 September 2026. The batteries, cable and charger have a line of their own.

Parts the Sideshift HB340 Retractable Houseboat Thruster’s box leaves to you, from the makers’ manuals read 30 September 2026. “What to ask for” is Sideshift’s own part or model where its manual names one, otherwise the dealer’s item.
Part What it is What to ask for Dealer price
Control-circuit fuse and switch A small fuse, and often a switch, on the thin wire that powers the panel or control box. Sideshift names none $8–$12Blue Sea in-line ATO fuse holders, at Fisheries Supply, read 16 October 2026.
Battery cable and lugs The two heavy cables from the battery to the motor, sized to the length of the run. The wiring calculator sizes them. 1/0 AWG (230 series) or 2/0 AWG tinned battery cable In the electrical line
Battery bank A cranking-type bank near the motor, sized by the maker's cold cranking amps. The battery calculator checks it. Sideshift names none In the electrical line
Charger or charge feed How the thruster bank gets charged: a shore charger of its own, a DC-to-DC charger or charging relay from the boat's system, or a charger built into the unit. NOCO GEN5X2, or a Victron Orion-Tr Smart isolated DC-DC charger $146–$305NOCO GEN5X2 shore charger, Victron Orion-Tr Smart DC-DC charger, Blue Sea ML-ACR charging relay, at Fisheries Supply.

The cost page has the whole list with what every maker says about each part.

For the yard and the installer

The full spec sheet, grouped the way a yard reads it. Every figure is the maker’s or a dealer’s, with its source.

The Sideshift HB340 Retractable Houseboat Thruster, every published figure the site holds, with where each came from.
Thrust and motor
Thrust Not published
Motor3.73 kW
Voltage12 V
Fitting
TypeExternal, drops down
End of the boatBow or stern
What it does to the hullThree small holes, all above the waterline
Haul-out to fit itNo: the maker says it goes on afloat
Maker’s boat lengthUp to 40 ft
Price and ordering
Price $5,995 full kit, the maker's own price, sideshift.com, 30 August 2026
Part number Not held for this listing
Documents
Manual Installation manual (PDF)on the maker's site
Warranty Sideshift gives 2 years against faulty workmanship or materials. Its exclusions include wrong wire size or low voltage, burn-out from overuse, collisions, and tangled line or netting. installation manual, Rev 3.1, p. 68
The site’s reviewSideshift thruster review

Draw, cable, fuse and battery, at each voltage

These are the maker’s own figures, at each voltage it is sold at. The cable is the size for the shortest run in the maker’s table. A longer run may need heavier cable, and the wiring calculator works that out for your own boat.

The Sideshift HB340 Retractable Houseboat Thruster’s draw, cable, fuse, battery and run limit, as the maker publishes them.
Voltage Draw Maker’s cable Fuse Battery Run limit
12 V 550 Astart current 2/0 AWG. The manual keeps the run to 10 ft of cable counted out and back. The FAQ allows the battery up to 40 ft from the controllerinstallation manual, Rev 3.1 Not published 1,700 CCA minimum, as two 12 V starting batteries in parallelSideshift installation manual, Rev 3.1, p.39, and the FAQ bursts of 3 to 5 seconds, never more than 20 to 30 seconds at a timeinstallation manual, Rev 3.1

What holds up and what to weigh

Each point names the fact it rests on.

What holds up

  • It goes on with the boat in the water. No haul-out is needed to fit it.Sideshift: "All Sideshift thrusters can be installed in-water since all the mounting locations and cable connections are routed above the waterline."
  • Sideshift sells it for either end, so it can go at the bow or the stern.The maker's listing

What to weigh

  • Sideshift publishes no thrust figure for it. The boat table uses our estimate from the motor's rating.The maker's published specs
  • It runs in bursts of 3 to 5 seconds, never more than 20 to 30 seconds at a time.installation manual, Rev 3.1

What the manual and listings say

This is the note we keep on the Sideshift HB340 Retractable Houseboat Thruster, written from the maker’s manual, its product pages and the dealer’s listing.

In the box: The kit has the thruster, the controller, the wireless joystick and key fob, the harness, the fuse and a battery switch. You buy the batteries, the cable and a charger. The joystick is wireless but needs 12 V at the helm for its own power.

Our note

Bolts to the underside of a houseboat's deck at the bow or the stern and retracts when not in use. Nothing goes through the hull. The manual's limit is 3 mph: retract it before running faster. It runs on two 12 V starting batteries in parallel (1,700 cold cranking amps) on 2/0 AWG cable, up to 40 ft from the controller. Sideshift publishes no weight limit for this one.

The HB350 gets 30 tons. Bursts only: the manual asks for pushes of 3 to 5 seconds as normal practice, and never more than 20 to 30 seconds at a time. Its warranty does not cover a motor burned out by overuse. On 17 September 2026 sideshift.com was running an end of summer sale, with ten percent off every thruster. The price here is the list price. The sale was still on when the page was read again on 2 October 2026.

Videos

One of Sideshift’s own videos, from its YouTube channel: the whole install, in four minutes. It is the maker’s pitch. Watch it for what the unit looks like and how it goes in, and take any claim back to the figures above.

Sideshift’s own video, on Sideshift’s YouTube channel. The picture is a still from it.

Other sizes and close alternatives

These are Sideshift’s next sizes in the same line, by thrust.

Sideshift prints no thrust, so we name no other maker’s unit as its match. The compare page lists every model.

Every model with a page here is listed, maker by maker, on the thruster index.

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.