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Yanmar

6L6N21L

Yanmar N-Series Marine Auxiliary Genset — Marinediesel, Bohrung 180 (6N18AL) / 210 (6N21AL) x Hub 280 (6N18AL) / 290 (6N21AL) mm, 720/750 or 900/1000 rpm, 6N18AL: 455-660 kW / 6N21AL: 745-1020 kW. Brennstoff: Marine Diesel Oil (MDO), Heavy Fuel Oil (HFO). Status: Discontinued (6N18AL-V/-SV/-EV/-UV/-HV series). 6N21AL-W series (DW/SW/EW/GW) current production. Verifiziert, Datenblatt verlinkt.

1260.0 kW
Power

Engine Specifications

6
Cylinders
210 mm
Bore
310 mm
Stroke
4-stroke
Stroke Type

Components & Design

Component data being added…

Technical Data

Displacement 6N18AL: 42.75L / 6N21AL: ~47L
Generator Capacity 6N18AL-SV: 662.5 KVA (560 kW) / 6N21AL-SV: 800 KVA (800 kW)
Compression Ratio 16.8:1
Oil Consumption <1.1 g/kWh
Exhaust Temperature ≤400°C
Configuration Vertical single-acting inline, 4-stroke, direct injection, compress air motor starting
power kw 1260
rpm 750
fuel type HFO/MDO
configuration L

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Common failures & inspection points

Turbocharger oil leakage causing intercooler clogging and boost pressure loss (documented symptom: <10% pressure drop indicates cleaning needed)

Inspect turbo seals, measure boost pressure, check intercooler for oil contamination

www.thehulltruth.com/boating-forum/...
Fuel injection system carbon deposits and water contamination causing injector blockage

Check fuel cleanliness, inspect injector nozzles for sludge, verify water separator function

www.atwildeplantparts.co.uk/blog/ho...
Seawater cooling system galvanic corrosion in coolers and cylinder head flange (exhaust valve area)

Check zinc anode wear, inspect cooler for corrosion pitting, examine cylinder head flange

www.cruisersforum.com/forums/f54/in...
Crankshaft journal ovality and cracks (documented case: 6N18AL-DV crank pin #4 with multiple cracks, 1.20mm undersizing required)

Measure crankshaft runout/ovality, visual crack inspection, check bearing clearances

www.marineengine.in/blog/2020/11/02...
Oil sludge accumulation from oxidation, water contamination, excessive idling reducing lubrication

Oil analysis for viscosity/water content, inspect oil cooler, verify change interval compliance

www.yammer.com/global/support/after...

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

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Equipment Model #124285 · ✓ still in production