"> Wärtsilä 6LW20 Auxpac
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Engines
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Wärtsilä

6LW20 Auxpac

The Wärtsilä 6LW20 Auxpac is a compact medium‑speed, four‑stroke L‑configuration diesel engine delivering up to 660 kW at 1200 rpm, designed for main propulsion or auxiliary power on small to mid‑size vessels.

Wärtsilä 6LW20 Auxpac
660.0 kW
Power

Engine Specifications

6
Cylinders
200 mm
Bore
280 mm
Stroke
4-stroke
Stroke Type

Components & Design

Component data being added…

Technical Data

Bohrung × Hub 200 × 280 mm
Hubraum pro Zylinder 8,8 l
Leistung pro Zylinder (aktuell) 185-220 kW (abhängig von Variante/Drehzahl)
Verdichtungsverhältnis 15:1
Spezifischer Brennstoffverbrauch (SFOC) 186-187 g/kWh (ISO-Bedingungen)
Motorkonfigurationen 4L20, 5L20, 6L20, 8L20, 9L20 (nur Reihe)
Gewichte (Reihe-Motor) 4L20: 6,8 t | 6L20: 8,3 t | 8L20: 10,5 t | 9L20: 11,1 t
Gewichte (Stromerzeuger) 4L20: 14,0 t | 6L20: 16,8 t | 8L20: 20,7 t | 9L20: 23,8 t
Kolben-Mittenfluß-Geschwindigkeit 8,4 m/s (900 rpm), 9,3 m/s (1000 rpm)
Ventile pro Zylinder 2 Einlass + 2 Auslass
Bauform 4-stroke, non-reversible, turbocharged & charge air cooling, direct injection
Ausführungen verfügbar Diesel (W20) & Dual-Fuel (W20DF, seit 2011)
Liefermenge seit 1990er >7500 Motoren insgesamt; >6000 W20DF-Einheiten
power kw 660
rpm 1200
fuel type HFO/MDO
configuration L

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Common failures & inspection points

Balance shaft bearing damage – can lead to major damage and downtime. Wärtsilä has developed a temperature monitoring system.

Perform continuous temperature monitoring of balance shaft bearings; check alarms

www.wartsila.com/services-catalogue...
Turbocharger overheating at higher speeds (1200 rpm upgrade) – new cooling pipe arrangement required. New KBB ST5 EP version is solution.

Turbocharger internal temperatures check; new cooling pipe installation at >1000 rpm operation verify

www.wartsila.com/insights/article/w...
Piston ring wear & cylinder liner scoring marks – early detection prevents critical wear and piston ring failure.

Visual inspection of cylinder liners every 4–8 weeks; piston crown check by mirror & flashlight

www.marineinsight.com/guidelines/re...
Fuel injection system wear (W20DF): pilot fuel injection nozzle can be damaged by cavitation erosion. Wärtsilä offers oil-cooled nozzle solution.

Einspritzdüsen auf Erosions-/Kavitations-Spuren inspizieren; Treibstoff-Filterung & -Sauberkeit überprüfen

www.wartsila.com/services-catalogue...
Pneumatisches Luftablass-Ventil (alt) – war ungenau. Neue hydraulische Lösung (Lisk-Ventil) in überarbeiteter Version.

Air release valve function check; on older engines check for hydraulics upgrade

www.wartsila.com/insights/article/w...

Type-general inspection and maintenance points for this equipment category — not model-specific.

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Equipment Model #123710 · ✓ still in production