5N21L
The Yanmar 5N21L is a medium-speed, 4‑stroke vertical inline diesel engine delivering up to 1 250 kW at 900 rpm, primarily used as an auxiliary power source on merchant vessels.
Engine Specifications
Other Cylinder Configurations 8
Components & Design
Component data being added…
Technical Data
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Common failures & inspection points
Inspect turbo seals, measure boost pressure, check intercooler for oil contamination
Check fuel cleanliness, inspect injector nozzles for sludge, verify water separator function
Check zinc anode wear, inspect cooler for corrosion pitting, examine cylinder head flange
Measure crankshaft runout/ovality, visual crack inspection, check bearing clearances
Oil analysis for viscosity/water content, inspect oil cooler, verify change interval compliance
Type-general inspection and maintenance points for this equipment category — not model-specific.
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Maritime Network →Manuals
- datasheet
- project_guide