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Max Power · tunnel thruster · bow or stern
Max Power ECO 90: specs, price and the boats it fits
It gives 198 lb (90 kgf) of push. Max Power sells it for boats of 28 to 46 ft. It runs on 24 V.
- Haul-out to install
- DIY 2 of 5: wiring prep only
- 3-year warranty
Quick stats
- Thrust 198 lb 90 kgf, Max Power's rating
- Boat length 28 to 46 ft Max Power's own range
- Price per lb of thrust Not worked out It needs a price and a thrust figure
- Voltage 24 V As sold
- Battery at 24 V 700 CCA Two batteries, near the thruster
- 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 Max Power ECO 90
The ECO 90 is Max Power’s entry to proportional control: the joystick sets how hard it pushes, so you can nudge the bow instead of jolting it. It gives 198 lb of push on 24 V in a 185 mm tube, for boats of about 28 to 46 ft, and the joystick and a control cable come with it.
Max Power publishes no price, so ask a dealer. It runs from a 24 V bank of two batteries, lead-acid or lithium; the ECO series is built for either, unlike Max Power’s on/off units. Add the tube, a main switch and a fuse. See the parts list.
Read more
Its brushless motor can run as long as there is power; once warm it keeps going at reduced thrust. A phone app (Android only) helps with troubleshooting. Warranty: two years, three if registered.
Installing it yourself? The installer section has every spec, and the Max Power thruster review sets this model against the rest of the Max Power range.
Where this summary comes from (5 sources, read 12 October 2026)
- Max Power product page
- Max Power ECO-PRO 90 / 110 / 130 installation manual, Version 4 (runs continuously, thrust reduced when hot; lithium voltage window)
- Max Power FAQ (standard units on lead-acid, AGM or gel; ECO PROportional built for lithium)
- Max Power: founded 1987 in Mandelieu, France; Lalizas Italia
- Max Power Warranty Conditions (three years; transferable; two hours of field labor in year one)
Will the Max Power ECO 90 steer your boat?
50 FT TRAWLER · BOW · 15 KT WIND
Every knot figure here is wind speed, not boat speed or current.
On a 50 ft trawler the Max Power ECO 90 (198 lb) steers her in a 16 knot breeze. Her bow needs about 168 lb from a tunnel to steer her in a 15 knot breeze.
The finder lists it for her.
The Max Power ECO 90 on a trawler, by length
- 25 ft32 kt
- 30 ft27 kt
- 35 ft23 kt
- 40 ft21 kt
- 45 ft18 kt
- 50 ft16 kt
- 55 ft15 kt
- 60 ft14 kt
- 65 ft12.5 kt
- 70 ft12 kt
- 75 ft11 kt
- 80 ft10 kt
Outlined: the finder does not list it at that length (under 13 kt, far more than she needs, or outside Max Power’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?
Every kind of boat it fits, by length
| Boat | Full thrust at 15 knots | Still 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 | 40 to 50 ft | None |
| Houseboat | 30 to 42 ft | 43 to 48 ftfull thrust to about 13 knots at 48 ft |
| Catamaran | 45 to 50 ft | None |
| Trawler | 39 to 50 ft | None |
| Motor yacht | 39 to 50 ft | None |
| 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 | 50 ft only | None |
| Center console | No length. More thrust than the boat needs. | |
The Max Power ECO 90 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. Here a houseboat gets full thrust to 42 ft, and a sailboat to 50 ft. The maker gives one range for every boat.
The table tries the Max Power ECO 90 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. So the table runs up to 50 ft, just past Max Power’s own range (28 to 46 ft).
It is sized for six kinds of boat here. 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
No US dollar price is published for the Max Power ECO 90, so we build no total for it. The yard’s share of the job is on the cost page.
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 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 DIYYou: 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
- 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.
- 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.
- 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 Max Power’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.
Know before you buy
What sets this model apart, what it costs to keep, and what to weigh.
Price per pound of thrust
There is no US price to divide by its thrust.
Controls
Proportional. Delivered without accessories: the fuse, holder and panel are bought.
Service and warranty
Max Power's website gives 3 years. Its manual gives 2, and 1 more if the warranty is registered within 3 months of installation. Outside pleasure craft it is 6 months. It transfers to the next owner, and the first year covers up to 2 hours of labor in the field.
See Max Power’s warranty Max Power's warranty conditions.Special mentions
Battery: at 24 V it wants two batteries of 700 CCA or more, Max Power's figure. The cheapest that meets it is the Optima BlueTop SC27DM Group 27 AGM, $359.99. Check your own bank.
Charger: a NOCO GEN5X2 two-bank shore charger, $146.41. It is the one our estimate prices.
Max Power 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.
No US dollar price is published for it, so we can work out no installed cost.
Parts for the Max Power ECO 90
See the Max Power ECO 90 manualSearch 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 manual button above opens it on the maker's site. It has the hull, wiring and fuse figures for this model.
From Max Power’s ECO Proportional 90, 110 and 130 installation manual, read 25 October 2026.
- In the box
- The manual: "The thruster is delivered with electric motor, controller with mega-fuse preinstalled, CAN panel, CAN cable (10 m)." The panel and its cable are in the box.
- Bought separately
- A fuse for the cables, because the built-in mega-fuse protects only the motor and controller. You also buy its holder, a manual battery isolator (Max Power advises one, beside the automatic isolator in the controller), the battery cable and the tunnel.
- Charging
- Max Power is the one maker that asks for both: the engine's alternator and a charger. A dedicated bank is optional and goes "as close as possible to the thruster". It wants starting-type batteries with high cold cranking amps.
In Max Power’s words, from its CT100 and CT125 installation manual, page 3: “The batteries used by the thruster must be charged by both the main engine's alternator and an appropriate battery charger.”
A yard job adds these parts on top of the unit: $541 to $1,369 for the priced ones, at Fisheries Supply’s prices on 30 September 2026 and 26 October 2026, plus the batteries, cable and charger. The cost page has what every maker says about each part.
Tunnel tube
Fisheries Supply lists it as “Sleipner fiberglass tunnel tube, 185 mm bore, 750 mm”.
Sold in lengths from about 30 to 60 in. This is the shortest: the yard cuts the tube to the width of your hull at the thruster. No Max Power tube is listed at this bore. This one is another maker's.
Main fuse
Fisheries Supply lists it as “ANL fuse 150 A”.
The maker's figure: 160 A ceramic or 150 A ANL.
Fuse holder
Fisheries Supply lists it as “ANL compact fuse block, 35 to 300 A, cable up to 2/0, with cover”.
Battery switch
Fisheries Supply lists it as “m-Series 300 A battery switch, on/off”.
Rated at or above the 150 A main fuse. If your manual names its own switch, use that one.
Control-circuit fuse holder
Fisheries Supply lists it as “Waterproof in-line ATO/ATC fuse holder”.
The maker asks for an 8 A fuse on the control supply.
Batteries
Fisheries Supply lists it as “Optima BlueTop SC27DM Group 27 AGM”.
You need 2, each at 700 CCA or more, in series for 24 V. The cheapest listing that meets it.
Battery cable, red and black
Defender lists it as “Ancor tinned battery cable 1/0 AWG, cut to length, red or black”.
You need 10 ft of each color. For about 20 ft of cable in all, out and back. Measure your run and check it against the cable table in the manual: never go smaller than it asks for.
Cable lugs
Fisheries Supply lists it as “Tin-plated starter lugs, 1/0 AWG, bag of 10”.
The listing runs $23.74 to $28.04 by stud size. Eight ends on one run, with two spare.
Charger
Fisheries Supply lists it as “GEN5X2 on-board charger, 10 A, 2 banks”.
Or a DC-to-DC charger from the house system: ask the electrician.
Outside the hull replacement parts in the water
Propeller (nut version)
The propeller on the drive. Max Power calls it “Propeller Ø185 (Nut Version)”.
Max Power prints two 185 mm propellers: 35040 and 636576 (Nut Version). Check which one your drive leg takes before ordering.
Propeller pin (drives the propeller)
The pin that locks the propeller to its shaft. Max Power calls it “Propeller Pin”.
The ECO 150 manual prints this 5 mm pin for its bronze 250 mm leg, where the composite 250 mm leg takes 312059. Confirm with Max Power for the ECO 150.
Drive leg (complete)
The leg under the motor that turns the propeller. Max Power calls it “Composite Leg”.
Drive leg gasket (seals the leg to the tunnel)
The leg under the motor that turns the propeller. Max Power calls it “Leg Gasket”.
The ECO 150 manual prints this gasket for its bronze 250 mm leg, where the composite 250 mm leg takes 310252.
Inside the boat replacement parts on board
Rubber coupling (flexible link between motor and drive leg)
The leg under the motor that turns the propeller. Max Power calls it “Rubber Coupling”.
Replacement motor
The electric motor that turns the propeller. Max Power calls it “MAXPOWER THRUSTER ECO 90 MOTOR KIT”.
No part matches. Try the number without spaces, or the part’s name.
The install parts are matched to Max Power’s own figures and priced at Fisheries Supply, with the battery cable at Defender, cut to length.
Spare part numbers come from Max Power’s parts pages and manuals. A dealer may sell a part we have not priced. Search for the number.
Other sizes and close alternatives
- Size down Max Power CT80 (12 V) 176 lb · $1,780
- Size up Max Power ECO 110 243 lb
- On/off Max Power CT80 (24 V) 196 lb · $1,780
- Other maker VETUS Bow Pro Boosted 90 198 lb · $5,528
- Other maker Quick BTQ 185 six sizes, 121 to 209 lb · $3,476 to $7,511
- Other maker Sleipner SE80/185T 212 lb · $3,285
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 and motor | |
|---|---|
| Thrust | 198 lb (90 kgf) As printed: 90kg |
| Motor | 5.3 kW |
| Voltage | 24 V |
| Run limit | Not published |
| Installation | |
| Type | Tunnel, fixed mount |
| End of the boat | Bow or stern |
| Tunnel diameter | 185 mm |
| What it does to the hull | Tunnel bore below the waterline |
| Haul-out to install it | Yes |
| Maker’s boat length | 28 to 46 ft |
| Price and ordering | |
| Price | No US price published |
| Part number | 636674Duo propeller, composite drive leg, proportional, 24 V |
| Documents | |
| Manual | Installation manual (PDF)on the maker's site |
| The site’s review | Max Power thruster review |
Every published figure the site holds for the Max Power ECO 90, with where each came from.
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.
| Voltage | Draw | Maker’s cable | Fuse | Battery | Run limit |
|---|---|---|---|---|---|
| 24 V | 260 Anominal draw | 1/0 AWG for up to 22 ft of cable counted out and back. Longer runs take heavier cableECO-PRO 90/110 / 130 installation manual | 160 A ceramic or 150 A ANLECO-PRO 90 / 110 / 130 manual | 700 CCA minimum, as the manual recommends DIN 395, SAE 700Max Power installation manual ECO-PRO 90 / 110 / 130, Version 4 | Not published |
The Max Power ECO 90’s draw, cable, fuse, battery and run limit, as the maker publishes them.
- At 24 V: size the cable for your run, or check the battery you have.
The tunnel: length and depth rules
Depth below the waterline. The minimum acceptable position is 139 mm below the waterline. Ideally the top of the installed tunnel sits 185 mm below it. Shallower than the ideal, the manual says, performance falls off progressively. CT100 and CT125 installation manual (July 2024).
Our notes from the manual and listings
In the box: Proportional. Delivered without accessories: the fuse, holder and panel are bought.
Our note
Proportional control: the joystick sets how hard it pushes. It sits in a 185 mm tunnel, for boats of 28 to 46 ft by the product page. The ECO proportional series is built to run on lithium (Li-ion or LiFePO4) as well as lead-acid, AGM or gel. The ECO 90 page promises unlimited run time until the battery runs out.
The standard CT100 manual rates its motor at two to three minutes. Max Power publishes no price and sells through dealers. Its Global Network page lists ten in the US.
Where each point above comes from
- Max Power 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
- No US dollar price is published for it, so we can work out no installed cost.The maker and the dealers the database reads
Not sure this is the one? The thruster finder asks about your boat and prices every unit that fits.