"> Wärtsilä 9LW20 Auxpac
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Wärtsilä

9LW20 Auxpac

The Wärtsilä 9LW20 Auxpac is a 9‑cylinder, medium‑speed (up to 1200 rpm) diesel/dual‑fuel generator set delivering ~990 kW, designed for auxiliary power on merchant vessels.

990.0 kW
Power

Engine Specifications

9
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 990
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 #123712 · ✓ still in production