Lagoon · Catamaran

Lagoon 400 & 400 S2

The Lagoon 400 is an 11.97 m cruising catamaran designed by VPLP (Marc Van Peteghem and Vincent Lauriot-Prévost) and built by Lagoon, part of Groupe Beneteau, from 2009. After more than 260 boats in a little under three years, Lagoon replaced it in 2012 with the 400 S2, which has a new interior by Nauta Design but the same hull, rig, tanks and standard engines of 2 × 29 hp with saildrive. Both came with 3 cabins (owner’s version) or 4, and with two to four heads. Lagoon’s last 400 inventory is dated October 2016; in 2017 the Lagoon 40, a different boat with a self-tacking jib and 2 × 45 hp, took its place. Lagoon names the engines as Yanmar 3YM30 only from 2015, and 40 hp and later up to 45 hp engines were options, so read the type plate before ordering engine parts.

Manuals & documents

The links go to Lagoon’s own documents — some as archived copies of pages the maker has since taken down. We host no manuals or drawings.

Equipment & its manuals

Standard equipment as the builder’s documents list it. Boats were ordered with options and refitted since — check what is actually aboard.

ItemModelManual / pageNote
EngineYanmar 3YM30 × 21,2,3Named in Lagoon’s inventories of September 2015, March 2016 and October 2016: 29 hp each, with saildriveYanmar 3YM30 Parts & service pageLagoon writes only “3YM30”, while Yanmar also built the later 3YM30AE with the same 29 hp, so read the engine plate before ordering parts. Standard with them: fixed two-blade propellers, a raw-water filter, mechanical throttles at the helm and a 12 V extractor fan for each engine room.
EngineDiesel 29 hp × 24,5,6,7,8Standard in Lagoon’s documents of 2009 to 2014 (spec sheets 11/2009, 01/2012 and 09/2013, websites 2011 and 2012): 2 × 29 hp with saildrive; maker not named—Neither the spec sheets nor the owner’s manuals (2010, 2012) name the engine type, so check the plate. The spec sheets list one 12 V 70 Ah starter battery per engine, a fuel filter with water separator and wet exhausts.
EngineOption: 2 × 40 hp, later up to 2 × 45 hp9,10,1,3,11,122 × 40 hp as an option in the Multihulls World test of July 2009 and on Cruising World’s 2010 test boat (Yanmar); Lagoon’s inventories of 2015 and 2016: “2 × 29 hp to 2 × 45 hp common rail”—None of these sources names the engine type of the options, so read the plate. Lagoon’s owner’s manuals give 58 kW as the boat’s maximum engine power.
SaildriveSaildrive × 211,1,13All years; Lagoon names no leg type, so read the plate on each legYanmar operation manual SD20 / SD50 / SD50-4T saildrives, March 2009Lagoon’s manuals: renew the leg and hull anodes before they have lost half their weight (on a new boat after the first 3 to 4 months), keep good metal contact with the drive, never paint them and use anodes for the water you sail in. The legs sit aft of the rudders.
Propeller2-blade fixed × 2 (folding: option)1,3,11,9Fixed two-blade propellers in the inventories of 2015 and 2016; the boat in the 2009 Multihulls World test had folding two-blade propellers—Lagoon chose the standard propellers in trials with the engine maker and advises against changing them without a specialist. Take folding propellers off at the end of each season, clean and grease them and check that the blades move freely.
Winches46.2 ST × 3 (46.2 STA from 2015)4,5,6,1,12Spec sheets 11/2009, 01/2012 and 09/2013: three 46.2 ST winches; inventories of 2015 and 2016: three 46.2 STAHarken Radial 46.2 ST installation and maintenance manualAll three sit at the helm on the port side of the aft coachroof and share halyards, mainsheet, reefs, genoa sheets and traveller between them. Lagoon gives the sizes in Harken’s code format without naming the maker, so check the drum before ordering parts. The 2010 user guide also shows electric winches for the mainsail and genoa (125 A breakers) and an optional electric davit winch (100 A), none of them in the standard lists.
WindlassQuick 12 V · 1000 W · 10 mm14,5,1,1112 V, 1000 W with a 10 mm gypsy in every spec sheet and inventory 2009–2016; Lagoon’s anchor package sheet of 02/2015 names Quick, with a gypsy for 10 mm or 3/8″ chain and 12–16 mm rope—Lagoon gives no model name, so read the windlass plate before ordering parts. The 100 A breaker is in the port aft cabin. Lagoon’s manual: anchor with the port engine running (with that engine down, switching on only its ignition lets the windlass draw on the service batteries, and the engine alarm sounds), motor up to the anchor instead of winching the boat, use a winch handle on the windlass if the power fails and rinse it with fresh water after each trip.
AnchorDelta 20 kg · 75 m × 10 mm · 20 m × 18 mm14,11Lagoon anchor package for the 400 S2, 02/2015: Delta 20 kg, 75 m of 10 mm (3/8″) chain and 20 m of 18 mm rope—Bridle of 2 × 6.20 m, 16 mm, with an 8 mm high-resistance shackle, fixed to the chainplates at the ends of the forward beam; 4 mooring lines of 20 m, 22 mm, and 6 fenders of 860 × 230 mm.
SteeringCable, wheel with brake, emergency tiller5,6,11Spec sheets 2009–2013: cable steering, stainless rudder stocks and an emergency tiller; helm on the port side against the coachroof bulkhead—Rack, cables, sheave box and the link rod between the rudders are reached through the engine compartment. Lagoon’s manual: check the cable tension regularly without overtightening, lubricate all parts and treat the nylon, Ertalon or Teflon bushes only with WD-40. The optional autopilot ram works on the steering rack.
AutopilotOption (maker not named)11,12Not standard; Lagoon’s manuals show the ram on the steering rack and, in the S2 manual, the course computer and gyro compass in the port transom; 60 A breaker in the 2010 user guide—Keep the autopilot compass at least 0.50 m away from wiring harnesses (Lagoon’s manual).
InstrumentsNone as standard5,3,12,11Every spec sheet and inventory 2009–2016 lists only an instrument console at the helm and a chart-table panel ready for electronics; Lagoon offered electronics packs as options—Lagoon’s manual: keep instruments and repeaters at least 1.50 m away from the radio loudspeakers.
ToiletManual marine head × 2–4 (electric: option)5,6,3,11Large manual marine toilets in all versions 2009–2016: two in the layouts with 2 bathrooms, three or four otherwise; electric toilets were an option—Lagoon gives no maker. Electric toilets run from a switch on the electrical panel; their 25 A breaker is under the port aft bed (S2 manual). Open the inlet and drain seacocks before use, flush with the lever slanted and dry the bowl with it upright, and use only absorbent paper.
Fridge12 V · 130 l, front-opening5,6,3,11,13All spec sheets and inventories 2009–2016; a second 110 l fridge or freezer was an option (top-opening in the S2 brochure)—Compressor fridge; Lagoon gives no maker.
StoveGas, 3 burners + oven5,6,1,113-burner hob and enamelled gas oven in all documents 2009–2016 (with grill in the 2009–2013 spec sheets); microwave optional—Gas locker under the starboard cockpit bench and room for a second bottle under the port “lazy boy” seat (6 kg in the 2015–2016 inventories). Close the gas valve and the regulator tap whenever the stove is not in use.
Water pump12 V pressure pump5,6,1,2,3,11All spec sheets and inventories 2009–2016; maker not named—The pump group is in the forward port cabin. Deck shower on the port transom: hot and cold in the 2009–2013 spec sheets and the October 2016 inventory, cold only in the 2015 and March 2016 inventories. An optional 12 V deck wash pump draws sea or fresh water (S2 manual).
Water heater40 l · 220 V + engine heat exchanger5,3,11All spec sheets and inventories 2009–2016: 40 l, heated electrically and by the starboard engine; 110 V for the US market (2012 spec sheet)—Located in the starboard aft cabin (S2 manual).
Bilge pump12 V automatic × 2 + manual × 25,3,11One automatic 12 V pump per hull, switchable from the panel, and two manual pumps in the aft cockpit, 2009–2016—Each hull has a sump under the floor. The forward compartments and engine bilges are watertight, with valved drains to the sump that stay closed in normal use. Shower water goes to its own 12 V sump pumps with float switch.
Batteries12 V: 2 × 140 Ah service + 2 start4,6,12,11,1Service 2 × 140 Ah throughout; start batteries: 1 × 70 Ah per engine (spec sheets 2009–2013, gel in 2013), 2 × 110 Ah (2010 user guide, inventories 2015–2016), 2 × 140 Ah (S2 manual 2012)—Service switch under the port aft bed, engine switches under both aft beds; the coupling handle in the starboard aft cabin lets one battery help start the other engine (turn it back afterwards). 100 A main fuse and shunt in the port aft cabin; two 80 A alternators in the 2015–2016 inventories.
Charger2 × 40 A12,11,3Shown in the 2010 user guide and the 2012 S2 manual; not in the standard spec sheets and inventories—In the port aft locker, reached through the port engine compartment; it charges from shore power or the generator.
GeneratorOption (maker not named)5,3,11,12A technical locker under the forward cockpit bench is prepared for it in all spec sheets and inventories 2009–2016—S2 manual: remote start at the chart table, its own starting battery, sea-water cooling with a water/exhaust separator and an earth plate under the hull; in the 2010 user guide a pull knob selects the port or starboard tank for its diesel.
Air conditioningOption: 44000 / 48000 BTU12,112010 user guide: 44000 BTU in the 3-cabin and 48000 BTU in the 4-cabin version, 110/220 V, on shore power or the generator—Reverse-cycle units, which can heat when the sea is above 10 °C; each compressor has its own overboard discharge above the waterline, so check the water flow after starting (S2 manual).
HeaterOption: 2 diesel air heaters11,12S2 manual: two 12 V diesel heaters of 5000 W, under the forward saloon bench and in the starboard aft cockpit locker, fed from the starboard tank; in the 2010 user guide they draw on both tanks—
DavitsMax 200 kg · tender up to 3.40 m11,12,5Owner’s manuals 2010 and 2012: davits for a tender of at most 3.40 m and 200 kg, hoisted with a cockpit winch (electric davit winch optional); not in the standard spec sheets—Nobody in the tender while it is raised or lowered; take its outboard off and stow it on board before sailing. An outboard on the pushpit must not weigh more than 60 kg.
Mast & riggingAluminium, deck-stepped, double spreaders5,6,3,11Anodised aluminium mast on the coachroof (P 15.69 m), aluminium boom with two lazy-jacks, two hull shroud chainplates and the forestay chainplate on the crossbeam, 2009–2016—Standing rigging per Lagoon’s manual: 2 shrouds, forestay, 2 × 2 diamonds and 2 martingale stays. The forestay is preset at 2.6° rake aft; retension the rig after the first trips and grease the bottle screws with tallow or graphite grease, never silicone. The mast wiring joins in a box in the forward cockpit locker.
SailsDacron: 56 m² main + 28 m² genoa5,3,11Full-batten high-roach mainsail with Lagoon logo and furling genoa with UV strip, 2009–2016; square-top main of 60.5 m², gennaker or Code 0 optional—Three reefs: 1 and 2 single-line, 3 conventional with a strap and snap shackle on the luff (S2 manual). Furler and sailmaker are not named.
Lights12 V halogen, later LED9,10,6,1Halogen lights on the early boats (Multihulls World 2009, Cruising World 2010; some still halogen in the 09/2013 spec sheet); LED inside and outside in the 2015–2016 inventories—
Hatches & portsFixed glass emergency exits11,6,15Escape panels in the hulls, reached from the aft cabins and the companionway steps; in a capsize you break the glass with the hammer kept next to the panel or in the liferaft locker (S2 manual)—Lagoon’s recall covers fixed Goiot emergency hatches on catamarans built 2007–2019: a retaining kit is fitted, and Goiot now says to replace these hatches every 10 years, kit or not. Ask a Lagoon dealer or service centre with your HIN whether your boat is concerned.
Fuel filterPre-filter with water separator × 211,5,1On the line from each tank to its engine, 2009–2016; the engine has its own fine filter—Lagoon’s manual: drain the bowl by loosening the knurled screw several times a year until clean diesel runs, change the pre-filter at least once a year, clean the tanks every 5 years and keep 20 % in reserve. The two 200 l rotomoulded tanks sit under the aft berths, with shut-off valves on the tanks.

Specifications

Years builtLagoon 400 from 2009 (spec sheet 11/2009, magazine test July 2009); 400 S2 from 2012 (owner’s manual 07/2012, brochure 09/2012); last inventory October 2016, replaced by the Lagoon 40 in 20174,9,11,13,3,16
VersionsLagoon 400 (2009–2012) and 400 S2 (from 2012): the S2 got a new Nauta Design interior (grey Alpi oak and Milano oak floor instead of light oak and wenge on Lagoon’s website) with the same hull, rig and data. Spec sheets: owner’s version with 3 cabins, 3 heads and a separate shower, or charter version with 4 cabins and 4 heads; Lagoon’s plans also show 3 cabins/2 bathrooms and 4 cabins/2 bathrooms. Equipment packs Essential, Cruising and Comfort in 2009, Essential and Comfort in the S2 brochures7,8,5,6,17,13,9
Hulls built264 of the original Lagoon 400 (Lagoon’s former-models page, December 2012; “over 260 in a little under three years” in the S2 brochure); Lagoon published no total for the S217,13
SuccessorLagoon 40 (2017), which replaced both the 400 and the 39: a new boat with 11.74 m hull length, 6.76 m beam, a self-tacking jib and 2 × 45 hp16,18
DesignerMarc Van Peteghem & Vincent Lauriot-Prévost (VPLP); interior of the 400 S2 by Nauta Design5,6,13
BuilderLagoon, Bordeaux (France), part of Groupe Beneteau6,13
Length overall11.97 m (39’3″); 12.53 m with the davits deployed (owner’s manuals)5,3,11
Waterline length11.45 m (37’7″)5,6
Beam7.25 m (23’9″)5,3
Draft1.21 m (4’)5,3
DisplacementLight (CE): 10.348 t on the spec sheets, 10.35 t in the S2 brochure and the inventories, 10.22 t in the 01/2011 brochure; 10.615 t in the S2 owner’s manual5,13,3,19,11
Max boat displacement15.08 t (2010 user guide); 15.394 t for design categories A and B, 15.345 t for C and D (S2 manual)12,11
Max. payload4.73 t in both manuals (4.779 t for categories C and D in the S2 manual), including crew at 75 kg each, full tanks, options and the liferaft12,11
Air draft20.30 m above the waterline (66’7″) on the spec sheets and inventories; the owner’s manuals give an air draught of 21.40 m5,3,11,12
Rig dimensions (I, J, P, E)I 15.56 m, J 4.10 m, P 15.69 m, E 5.30 m11,12
Bridgedeck clearance0.55 to 0.70 m (measured in the 2009 Multihulls World test; Lagoon gives no figure)9
Sail area84 m² upwind (56 m² mainsail + 28 m² genoa)3,13
Mainsail56 m² full-batten (603 sq ft); 45, 32.48 and 20.20 m² with 1, 2 and 3 reefs; square-top mainsail of 60.5 m² (651 sq ft) as an option5,11
Genoa28 m² furling genoa (301 sq ft); reference reefing marks at 21 and 16 m² (S2 manual)5,11
Gennaker / Code 0Optional gennaker of 76 m² (spec sheets 2009–2012) or 70 m² (manuals); Code 0 of 73 m² (09/2013 spec sheet and inventories 2015–2016); asymmetric spinnaker of 145 m² (manuals)5,6,3,11
Engine2 × 29 hp with saildrive as standard throughout; options 2 × 40 hp (tests 2009/2010) and up to 2 × 45 hp common rail (inventories 2015–2016); maximum 58 kW (manuals)5,3,9,10,11
Fuel tank2 × 200 l (2 × 53 US gal), rotomoulded, under the aft berths5,3
Water tank300 l (79 US gal) in the bow; a second 300 l tank was optional5,11
Holding tank80 l per tank, with deck pump-out: one for the port aft head as standard (spec sheets 2009–2013, inventories up to March 2016), the others optional; the October 2016 inventory lists one 80 l tank per head5,6,2,3,11
Cabins3 or 4 double cabins with 2, 3 or 4 heads; in the owner’s version the whole starboard hull is the owner’s, with desk, sofa and a bathroom with separate shower6,3,17
Berths6 to 12 (inventories 2015–2016)1,3
Berth sizesAft doubles 2.00 × 1.44 m (1.00 m at the foot); forward doubles 2.06 × 1.76 m (1.16 m at the foot), convertible into two singles of 2.06 × 0.69 m6,3
HeadroomSaloon 2.12–2.13 m, cabins 1.98–2.08 m, heads about 2.00 m6,3
CE categoryA: 12 people, B: 14, C: 20, D: 20 (spec sheets 2009–2013 and manuals); Lagoon’s website from 2011 and the inventories 2015–2016 give A: 105,6,11,7,3
HullPolyester with anti-osmosis resin; infused balsa-cored hulls with solid laminate below the waterline; balsa-cored deck and bridgedeck; laminated or bonded plywood bulkheads5,3

Good to know

  • Lagoon’s English owner’s manual for the 400 S2 (update 07/2012) is still readable as an archived PDF from Lagoon’s old website, and the French user guide of 10/2010 covers the original 400. For a manual matching your hull, ask your dealer; failing that, Lagoon sends the PDF on request to info@catamarans-lagoon.com.11,12,20
  • Before ordering engine parts, check which engines a used 400 really has: Lagoon’s documents give 2 × 29 hp saildrive diesels as standard throughout and name them Yanmar 3YM30 only from 2015, testers in 2009 and 2010 sailed boats with optional 40 hp engines, and the 2015–2016 inventories offer up to 2 × 45 hp common rail. The type plate decides which filters, impellers and belts fit.5,1,9,10
  • The 400 and 400 S2 were built within the period of Lagoon’s recall of fixed Goiot emergency hatches (catamarans of 2007–2019): if your escape hatches are fixed Goiot units, make sure the retaining kit is fitted, and note that Goiot now advises replacing them every 10 years. Contact a Lagoon dealer or service centre with the model and HIN.15,11
  • From Lagoon’s manual: open the engine water-intake valves before starting and check right away that water comes out with the exhaust; close them when the boat is left for long. Brush the hull strainers at every haul-out and never paint over them, and never run the engines or turn the propellers with the boat out of the water.11
  • For the yard: Lagoon’s manual asks for lifting straps of at least 11 m and shows where to place them; ashore, put a 1 m block under the aft end of each keel and a steel stand at least 1 m high under the forward bulkhead, lowering the bow onto it only once the keels sit firmly. The wetted area including appendages is about 46 m² for working out the antifouling.11
  • Lagoon’s trim guide for the 400 S2, close-hauled in apparent wind: first reef at 20 knots, 75 % genoa from 26, second reef with 60 % genoa from 30, 40 % genoa from 36 and the third reef alone from 45 knots; in rough seas reduce about 10 % earlier. Never carry the full genoa with two reefs in the main: Lagoon warns this can break the mast.11

Videos & how-tos

Links to YouTube, nothing embedded. The maker’s own channel comes first; the rest are channels we found clear and correct for this model.

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Sources

  1. web.archive.org/web/20151231084504/http://www.cata-lagoon.com/documentation/pdf/specs_LAG…
  2. web.archive.org/web/20160516110030/http://www.cata-lagoon.com/documentation/pdf/specs_LAG…
  3. web.archive.org/web/20170809040656/http://www.cata-lagoon.com/documentation/pdf/specs_LAG…
  4. web.archive.org/web/20100815011544/http://www.cata-lagoon.com/site_agents/pdf/spec_l400_A…
  5. web.archive.org/web/20120817072524/http://www.cata-lagoon.com/site_agents/pdf/spec_l400_A…
  6. web.archive.org/web/20140316222904/http://www.cata-lagoon.com/documentation/pdf/spec_l400…
  7. web.archive.org/web/20111013062249/http://www.cata-lagoon.com/lagoon_400_specifications_u…
  8. web.archive.org/web/20120830184138/http://www.cata-lagoon.com/lagoon_400s2_specifications…
  9. web.archive.org/web/20160126001905/http://www.cata-lagoon.com/documentation/article_press…
  10. cruisingworld.com/sailboats/lagoon-400-home-thats-home-afloat/
  11. web.archive.org/web/20150922002134/http://www.cata-lagoon.com/documentation/pdf/manuel_pr…
  12. web.archive.org/web/20151106073248/http://www.cata-lagoon.com/documentation/pdf/user_guid…
  13. web.archive.org/web/20130809224508/http://www.cata-lagoon.com/documentation/pdf/Lagoon400…
  14. web.archive.org/web/20151106031728/http://www.cata-lagoon.com/documentation/pdf/anchor_ki…
  15. catamarans-lagoon.com/news/article/recall-goiot-products
  16. multihulls-world.com/review/catamaran/lagoon-40-a-clever-and-sharp-40-footer
  17. web.archive.org/web/20121203184120/http://www.cata-lagoon.com/lagoon_anciens_400_uk.php
  18. catamarans-lagoon.com/boats/lagoon-40
  19. web.archive.org/web/20130801041607/http://www.cata-lagoon.com/documentation/pdf/Lagoon400…
  20. help.catamarans-lagoon.com/hc/en-us/articles/7408853722525-Owner-s-manual

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