Yanmar · Inboard diesel

Yanmar 4JH45 / 4JH57

The 4JH45, 4JH57, 4JH80 and 4JH110 are Yanmar’s four-cylinder common-rail marine diesels (the JH-CR series), built since 2013/14 and still in the range; earlier JH engines such as the 4JH4 and 4JH5E had mechanical injection. The 45 and 57 share a naturally aspirated 2.19 l block, the 80 and 110 a turbocharged, intercooled 2.0 l block, and together they are the usual engines of 40–50 ft charter catamarans and monohulls such as the Lagoon 40, 42 and 46, Leopard 45 and 46 or Jeanneau Sun Odyssey 410 to 490, mostly with the SD60 saildrive. Oil filter, both fuel filters, the impeller and the other seawater pump wear parts, thermostat and pressure cap are the same on all four. Injectors, mixing elbows, air intake parts and heat exchanger O-rings differ between the 45/57 and the 80/110, only the 45 and 57 have glow plugs, and on the 80/110 the belt depends on whether the seawater pump sits at the rear (standard) or at the front.

Manuals & documents

The links go straight to Yanmar. We host no manuals or drawings — the manufacturer’s copy is the current one.

Wear parts & part numbers

PartOEM numberAlso fitsNote
Impeller kit (with gasket)129670-426101,2,3,4,5replaces 129670-42531—All four engines; front- and rear-mounted pumps take the same impeller. Kit with impeller, four cover screws and cover O-ring, catalogued from engine no. E12138 (4JH45), E12113 (4JH57), E51216 (4JH80) and E51211 (4JH110); Diesel Parts Direct shows the loose impeller 129670-42531 replaced by the kit.
Impeller puller129671-921106,2—Named in the operation manual; it grips the impeller by its M18 thread.
Engine oil filter129150-351701,2,3,7—All four engines (the same filter in both Yanmar catalogues). Yanmar-branded; the catalogues list the unbranded 129150-35153 as fully interchangeable. Hand-tight plus 3/4 turn, 20–24 N·m.
Fuel filter (engine)129A00-558006,1,2,3,8—Engine-mounted spin-on filter, all four engines. The 2020 catalogues add the Yanmar-branded 129A00-55810 as fully interchangeable. Tighten to 20–24 N·m and prime with the hand pump.
Fuel pre-filter121857-557106,1,2,3,9—Element of the pre-filter with water separator 119172-55800 (later 119172-55801) supplied with all four engines. Move the water-in-fuel sensor over to the new element.
Air filter129271-123111,2—4JH45 and 4JH57 only. Yanmar lists no separate element: this insert of intake silencer 129670-12290 is the part you clean every 250 h with mild detergent and replace when damaged.
Air filter129470-123303—4JH80 and 4JH110 only: element of intake silencer 129470-12301. Does not fit the 4JH45/4JH57.
Alternator V-belt129675-422801,2,3,10—6PK V-ribbed belt for alternator, coolant pump and front-mounted seawater pump: 4JH45, 4JH57, and 4JH80/4JH110 with the optional front pump.
Alternator V-belt129677-422803,11,12—Only for the 4JH80 and 4JH110 with the rear-mounted seawater pump, their standard layout.
Alternator V-belt128790-775801,2,3,13—6PK belt for the optional second-alternator kit 129677-77600; all four engines, only where that kit is fitted.
Thermostat129470-498011,2,3,14—76.5 °C; all four engines.
Thermostat gasket129150-498111,2,3—All four engines. The thermostat cover gasket is 129795-49551, also common to all four.
Pressure cap129673-441311,2,3,15—Filler cap on the heat exchanger; all four engines.
Heat exchanger end-cap O-ring129670-441501,2,16—4JH45 and 4JH57: two per engine, 74.5 × 3 mm. Cooler core 129670-44460.
Heat exchanger end-cap O-ring127677-330603—4JH80 and 4JH110: four per engine. Cooler core 129677-44020.
Pump cover O-ring119773-425701,2,3—End-cover O-ring of the seawater pump, all four engines; included in impeller kit 129670-42610 and wear kit 129670-42590.
Water pump plate129670-425401,2,3,17—Wear plate of the seawater pump; all four engines.
Water pump repair kit129670-425901,2,3—Seawater pump wear kit: end cover, wear plate, washer, mechanical seal, retaining ring and O-ring; all four engines, catalogued from the same engine numbers as the impeller kit. Shaft kit (shaft, key, bearings, seals): 129670-42600.
Raw water pump129271-425021,2,3,18,19—Front-mounted pump: standard on the 4JH45 and 4JH57, optional on the 4JH80/4JH110. Mounting gasket 129150-01881. Diesel Parts Direct shows it replaced by 129271-42503; that number is not yet in the June 2020 catalogues, so check with your dealer.
Raw water pump129670-425133,20,12—Rear-mounted pump of the 4JH80 and 4JH110, their standard layout according to Yanmar’s datasheet. Mounting gasket 129150-01881.
Water pump gaskets129150-018811,2,3—Mounting gasket of the seawater pump; all four engines, front or rear pump.
Exhaust mixing elbow129670-135611,2,21—4JH45 and 4JH57, standard L-type elbow. The optional U-type (riser) elbow is 129470-13541; both take gasket 129472-18090.
Exhaust elbow gasket129472-180901,2—4JH45 and 4JH57, L-type and U-type elbow.
Exhaust mixing elbow129673-135523,22—4JH80 and 4JH110, standard elbow on the turbocharger outlet. Optional U-type elbow assembly 129472-13501.
Exhaust elbow gasket129472-135203—4JH80 and 4JH110: gasket between turbine outlet and mixing elbow.
Fuel injector129675-531001,2—Common-rail injector for the 4JH45 and 4JH57, four per engine; does not fit the 4JH80/4JH110.
Fuel injector129677-531003—Common-rail injector for the 4JH80 and 4JH110, four per engine.
Injector gasket129978-118711,2,3—The same gasket on all four engines.
Glow plug129008-778001,2,3—4JH45 and 4JH57 only, four per engine. The 4JH80/4JH110 catalogue lists no glow plugs.
Valve cover gasket129C00-113101,2,3—All four engines.
Crankcase breather element123907-031001,2,6—Breather diaphragm in the rocker cover, 4JH45 and 4JH57 only; Yanmar has the dealer check it every 1000 h.

Numbers checked against the sources below on 13 October 2026. Always confirm against your serial number and exact type before ordering.

Service intervals

TaskInterval
First serviceAfter the first 50 h: change engine oil and filter and gear oil (and its filter where fitted), drain the fuel tank, check belt tension and control cables; the dealer adjusts the valve clearance and checks shaft alignment6
Engine oil changeEvery 250 h or yearly, first time after 50 h6
Oil filterEvery 250 h or yearly, first time after 50 h6
Fuel filterEvery 250 h or yearly6
Fuel pre-filterDrain the water separator every 50 h or monthly; replace the element every 250 h or yearly6
Drain fuel tankDrain water and sediment after the first 50 h, then every 250 h or yearly6
Air filterClean the intake silencer element every 250 h or yearly6
Turbocharger wash4JH80/4JH110: wash the turbocharger blower every 250 h or yearly (dealer)6
Raw water impellerInspect every 250 h or yearly; replace every 1000 h or 4 years even if it looks fine6
V-belt checkAdjust after the first 50 h, then check every 250 h or yearly6
V-belt replaceEvery 1000 h or every 4 years6
Coolant changeYearly; every 2 years with long-life coolant6
Exhaust elbow checkClean and inspect every 250 h or yearly; replace every 500 h or 2 years6
Gearbox oil changeFirst after 50 h, then every 250 h or yearly (KM and ZF gearboxes; the SD60 saildrive has its own schedule)6
Valve clearanceFirst at 50 h, then every 1000 h or 4 years (dealer)6
Heat exchanger cleanClean and check the seawater passages every 1000 h or 4 years (dealer)6
Crankcase ventilation4JH45/4JH57: check the breather diaphragm every 1000 h or 4 years (dealer)6
Hoses & clampsReplace the rubber fuel and water hoses every 2 years6
BatteryCheck the electrolyte level every 50 h or monthly6

From Yanmar’s JH-CR operation manual (16th edition, September 2025) for the 3JH40, 4JH45, 4JH57, 4JH80 and 4JH110; hours or time, whichever comes first. The SD60 saildrive has its own schedule (see our SD50/SD60 page).

Specifications

Cylinders4 in-line, four-stroke, water-cooled, direct injection6
Aspiration4JH45/4JH57: naturally aspirated; 4JH80/4JH110: turbocharged with intercooler6
Displacement4JH45/4JH57: 2.190 l; 4JH80/4JH110: 1.995 l6
Bore × stroke4JH45/4JH57: 88 × 90 mm; 4JH80/4JH110: 84 × 90 mm6
Power4JH45: 33.1 kW (45 mhp) at 3000 rpm, 30.1 kW continuous at 2907 rpm; 4JH57: 41.9 kW (57 mhp) at 3000 rpm, 38.1 kW continuous; 4JH80: 58.8 kW (80 mhp) at 3200 rpm, 53.5 kW continuous at 3101 rpm; 4JH110: 80.9 kW (110 mhp) at 3200 rpm, 73.6 kW continuous (ISO 8665, at the crankshaft)6
Rated speed3000 rpm (4JH45, 4JH57); 3200 rpm (4JH80, 4JH110)6
InjectionBosch common rail with electronic control of injection timing and pressure6
Injection pressureup to 160 MPa6
CoolingFresh-water (coolant) circuit with heat exchanger; seawater pump with rubber impeller. 4JH80/4JH110: seawater pump at the rear as standard, at the front as an option12
Thermostat opens at76.5 °C1,2,3
Engine oil capacity4JH45/4JH57: 5.0 l at a 7° installation angle (KM35P, ZF30M, ZF25), 5.5 l at 0° (KM35A2, KM4A1, ZF25A, SD60, bare engine); 1.4 l between the dipstick marks. 4JH80/4JH110: 5.5 l at 7° (ZF30M, ZF25), 6.7 l at 0° (KM4A2, KMH4A, ZF25A, KMH50V, SD60, bare engine); 2.4 l between the marks. Totals including the filter6
Engine oil gradeAPI CD, CF, CF-4, CI or CI-4; SAE 10W-30 or 15W-40 all year6
Coolant capacity4JH45/4JH57: 6.0 l in the engine + 0.8 l in the reservoir; 4JH80/4JH110: 7.2 l + 0.8 l6
CoolantLong-life coolant (LLC) mixed with soft water at 30–60 %; never mix brands6
FuelDiesel to EN 590 or ASTM D975 S15 (max. 15 ppm sulphur in the USA and Canada), cetane 45 or higher; biodiesel blends up to B7 only6
Alternator4JH45/4JH57: 12 V 125 A; optional second alternator 12 V 125 A or 24 V 60 A23
Starter motor4JH45/4JH57: 12 V 1.4 kW23
Belt tension8–9 mm deflection under 100 N at mid-span, after 5 minutes at idle6
Dry weightEngine only: 220 kg (4JH45/4JH57), 229 kg (4JH80/4JH110); with SD60 saildrive: 264 kg (4JH45/4JH57), 274 kg (4JH80)6
Gearbox4JH45/4JH57: KM35P, KM35A2, KM4A1, ZF30M, ZF25/ZF25A or SD60-5 saildrive (flywheel housing SAE #5). 4JH80: ZF30M, ZF25/ZF25A, KM4A2, KMH4A, KMH50V or SD60-4 saildrive (SAE #4). 4JH110: as the 4JH80 but without the SD60; Yanmar’s datasheet also lists the SD15 saildrive for the 80/1106,12
Gearbox oilKM gearboxes: SAE 20 or 30, API CD (KM35P 0.5 l, KM35A2 0.65 l, KM4A1 2.3 l, KM4A2 3.0 l, KMH4A 2.0 l); ZF gearboxes: ATF; SD60: 3.1 l (3.3 l with the extended leg) of SAE 15W-40, API CD or higher6
Emissions4JH45/4JH57: EU RCD 2, BSO II; US EPA Tier 323
Years builtSince 2013/14: operation manual first issued in October 2013, both parts catalogues in July 2014; all four engines are still in Yanmar’s range6,1,3

Good to know

  • There is no zinc anode on the engine itself: neither Yanmar parts catalogue lists one, in the heat exchanger or anywhere else. Corrosion protection sits on the SD60 leg or the propeller shaft, so check those anodes instead (see our SD50/SD60 page).2,3
  • Carry the impeller kit 129670-42610 and the puller 129671-92110 that the manual names. Yanmar wants the impeller replaced every 1000 h even if it looks fine; fit the new one with its M18 thread facing the cover so the puller can grip it next time.6,2
  • The 4JH80 and 4JH110 normally have the seawater pump at the rear, which takes belt 129677-42280 instead of the front-pump belt 129675-42280. Check where your pump sits before ordering a belt.3,12
  • Common-rail injection does not tolerate water or dirt. Drain the water separator every 50 h or monthly, renew both fuel filters every 250 h, and prime with the hand pump (about 60 strokes) rather than the starter. The engine filter bleeds itself; only the pre-filter has a bleed screw.6
  • Use low-sulphur diesel with no more than 7 % biodiesel (B7); Yanmar’s fuel requirements also say not to add biocide.6
  • Oil capacity depends on installation angle and gearbox (5.0 to 6.7 l), so fill to the dipstick rather than to a fixed figure: the marks are 1.4 l apart on the 45/57 and 2.4 l on the 80/110. Never overfill.6

Fitted in

Boats whose builder lists it as standard or optional equipment:

  • Lagoon 42 — Yanmar 4JH45 × 2 (Standard 2015–2023: 45 hp common rail with saildrive in the inventories of October 2015, April 2018 and July 2020, the brochures up to 07/2020 and the configurator 2019–2022; Lagoon’s page still showed 2 × 45 hp in March 2023)
  • Lagoon 42 — Yanmar 4JH57 × 2 (Option in the configurator of 2019, 2020 and 2022 (the inventories say “up to 2 × 57 hp CR”); standard 2 × 57 hp on Lagoon’s pages from September 2023 and on the 42 Millenium)
  • Lagoon 46 — Yanmar 4JH45 × 2 (Standard on 2019–2020 boats: inventories of January/May 2019 and July 2020, configurators of March 2019 and June 2020 and the July 2020 brochure (45 hp, common rail, with saildrive))
  • Lagoon 46 — Yanmar 4JH57 × 2 (Option on 2019–2020 boats (‘Extra for 2 × 57 HP (Yanmar 4JH57)’ in the March 2019 configurator; in June 2020 it appears in the folding-propeller and electronic-throttle options); Lagoon’s pages of 2021–2023 list 2 × 45 or 2 × 57 hp, the current 46 and 46 Iconic pages 2 × 57 hp as standard)
  • Leopard 42 — Yanmar 4JH45 × 2 (2nd generation: 45 hp each, with saildrives)
  • Leopard 45 — Yanmar 4JH45 × 2 (All Leopard 45: 45 hp (33 kW) common-rail engines with saildrives)
  • Bavaria C42 — Yanmar 4JH57 (Diesel C42, option: 41.9 kW (57 hp) with saildrive and a three-blade folding propeller; named in the 2020 brochure and the price list of October 2021)
  • Beneteau Oceanis 40.1 — Yanmar 4JH45 (All boats: 45 hp common rail on a propeller shaft, in every list from July 2020 to October 2025)
  • Jeanneau Sun Odyssey 440 — Yanmar 4JH45CR (Standard; the type is written out in the lists of November 2019, January 2021 and September 2023, while the October 2017 page and the 2017–2019 brochures only say ‘Yanmar 45 hp / 33 kW’)
  • Jeanneau Sun Odyssey 440 — Yanmar 4JH57CR (Option; on the model page by November 2018 (not yet in October 2017) and in the lists from November 2019; the 2017 to 2025 brochures print only the 45 hp engine)

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Sources

  1. mecanique-plaisance-finistere.com/yanmar/pdfmoteur/4jh454jh57.pdf
  2. leon-marine.com/wp-content/uploads/2021/02/4JH45-57.pdf
  3. leon-marine.com/wp-content/uploads/2021/02/4JH80-110.pdf
  4. dieselpartsdirect.com/ym12967042610
  5. dieselpartsdirect.com/ym12967042531
  6. yanmar.com/marine/wp-content/uploads/2025/10/0AJHC-EN001F-Sep.2025-0_JH-CR_OPM_20250917.p…
  7. dieselpartsdirect.com/ym12915035170
  8. dieselpartsdirect.com/ym129a0055810
  9. dieselpartsdirect.com/ym12185755710
  10. dieselpartsdirect.com/ym12967542280
  11. dieselpartsdirect.com/ym12967742280
  12. yanmar.com/marine/wp-content/uploads/2021/02/DS_4JH80-110_A4_052022_HR.pdf
  13. dieselpartsdirect.com/ym12879077580
  14. dieselpartsdirect.com/ym12947049801
  15. dieselpartsdirect.com/ym12967344131
  16. dieselpartsdirect.com/ym12967044150
  17. dieselpartsdirect.com/ym12967042540
  18. dieselpartsdirect.com/ym12927142502
  19. dieselpartsdirect.com/ym12927142503
  20. dieselpartsdirect.com/ym12967042513
  21. dieselpartsdirect.com/ym12967013561
  22. dieselpartsdirect.com/ym12967313552
  23. yanmar.com/marine/wp-content/uploads/2021/02/DS_4JH45-57_A4_022021_HR.pdf

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