Model Variants:
6LY2-STE, 6LY2A-STP, 6LYA-STP
Application:
Marine diesel engine - propulsion and auxiliary duty
Production Years Covered:
N/A - exact build years not stated in this manual
Document Type:
Service Shop Repair Manual
Engine Family:
Yanmar 6LY2 / 6LYA inline six marine diesel
Coverage Scope:
Complete engine, fuel, cooling, electrical and base engine service
Target Audience:
Marine technicians, boatyards, fleet mechanics and owner-operators doing their own service
Intended Use:
Professional shop repair and overhaul as well as do-it-yourself maintenance
Platform Class:
Inline six-cylinder high-output marine diesel in the 6.5 litre class
Primary Advantage:
Factory-level procedures for a specific engine family rather than generic diesel guidance
Illustration Style:
Detailed photos plus exploded diagrams and line drawings
Fault Finding:
General troubleshooting section for running and starting complaints
Service Procedures:
Step-by-step repair instructions with component-level detail
Manual Type:
Service Shop Repair Manual
Binding:
Digital - no physical binding
Delivery Method:
Instant download after purchase
Printable:
Yes - pages can be printed for shop use
Searchable Text:
Yes - standard PDF text search
Illustrations:
Detailed photos and illustrations
Diagrams:
Exploded diagrams and drawings
Coverage Areas:
Engine mechanical, fuel system, cooling system, lubrication, electrical and troubleshooting
Base Engine:
Cylinder block, cylinder head, pistons, connecting rods, crankshaft and bearings
Valve Train:
Camshaft, valves, springs, guides and valve clearance adjustment
Fuel System:
Direct injection pump, injectors, fuel lines and filtration
Lubrication System:
Oil pump, oil cooler, filter housing, galleries and pressure checks
Cooling System:
Seawater pump, freshwater pump, heat exchanger, aftercooler and thermostats
Intake and Turbocharging:
Turbocharger, aftercooler circuit and intake manifold
Exhaust System:
Exhaust manifold, mixing elbow and related checks
Electrical System:
Glow plug cold start circuit, starter, alternator, sensors and wiring
Marine Gear Interface:
Flywheel housing, damper and coupling service points
Troubleshooting:
General fault finding for starting, running, overheating, smoke and power loss
Disassembly:
Ordered teardown procedures with torque and clearance references
Inspection:
Wear measurement of bores, journals, valves and bearings
Overhaul:
Cylinder head reconditioning and bottom-end rebuild steps
Reassembly:
Component refit with specified clearances and fastener torque
Adjustment:
Valve clearance, injection timing and belt or gear alignment as applicable
Testing:
Compression, oil pressure and cooling system checks
Preventative Maintenance:
Fuel, cooling, lubrication, electrical and exhaust system checks
Technical Depth and Parts
Measurement Units:
Metric with imperial conversions where given
Parts Information:
Component identification and part breakdown references shown in exploded views
Specification Source:
Factory workshop data for the 6LY2 series variants
File Format:
PDF (searchable, bookmarked, zoomable)
Compatibility:
Windows, macOS, Linux, iOS, and Android — any device with a PDF reader
Requirements:
A PDF reader application (e.g. Adobe Acrobat Reader, free)
Searchability:
Fully text searchable for fast lookup of any topic
Print Quality:
High-resolution digital pages, printable at full clarity
Binding Type:
N/A — digital download, no physical binding
Paper Type:
N/A — digital download, no physical paper
Engine Type:
Diesel, four-stroke
Cylinder Configuration:
Inline 6-cylinder
Displacement:
Approx. 6.5 litres (common for this engine family)
Charge Cooling:
Aftercooled
Fuel Injection:
Direct injection
Power Output:
Approx. 370 kW (500 HP) - specific to model variant
Torque:
N/A - not specified in this manual
Rated Speed:
N/A - refer to engine nameplate for the exact rating
Cooling System Type:
Seawater cooled or keel cooled (typical marine arrangement)
Cold Start Aid:
Glow plugs
Major Components Covered:
Base engine and all bolt-on marine systems
Standard Transmission:
N/A - marine gear is matched by the boat builder, not supplied by Yanmar with this engine
Optional Transmission:
N/A - no specific gearbox is listed for these variants
Engine-to-Gear Interface:
Flywheel housing and damper coupling covered in the manual
Control Interface:
Mechanical throttle and gear cable connections at the engine
Reduction Ratio:
N/A - determined by the installed marine gear
Propeller Matching:
N/A - not specified for this engine family
Wheelbase:
N/A - applies to road vehicles, not this marine engine
Overall Length:
N/A - not specified in this manual
Width and Height:
N/A - not specified in this manual
Curb Weight:
N/A - dry engine mass varies with marine gear and is not listed
Crash Test Information:
N/A - not applicable to a marine diesel engine
Emission and Safety Compliance:
N/A - certification depends on the installation and market
Active and Passive Protection
Engine Protection Devices:
Low oil pressure and high coolant temperature alarm switches (typical fitment)
Overheat Protection:
Thermostat-controlled cooling with expansion tank and alarm circuit
Overspeed and Shutdown:
N/A - shutdown hardware is installation dependent
Operator Safety Notes:
Manual covers safe handling of pressurised fuel, hot surfaces and rotating components
Fuel Delivery Control:
Mechanical direct injection with governor control
Cold Start Technology:
Glow plug assisted starting
Monitoring:
Oil pressure and coolant temperature sender circuits detailed in the electrical section
Infotainment and Driver Assistance
Audio System:
N/A - not applicable to a marine engine
Driver Assistance:
N/A - vessel electronics are outside the scope of this manual
Oil and Filter Change:
Per manufacturer schedule - refer to the maintenance chart in the manual
Fuel Filter Change:
Per manufacturer schedule - refer to the maintenance chart in the manual
Impeller and Cooling Service:
Inspect regularly; seawater pump impeller is a common wear item
Engine Oil:
Refer to the manual for the required viscosity and API classification
Coolant:
Refer to the manual for the specified mix and inhibitor
Known Issues and Wear Items
Common Wear Items:
Seawater pump impeller, thermostats, injector nozzles and heat exchanger elements
Routine Checks:
Fuel system checks, cooling system checks, lubrication checks, electrical checks and exhaust system checks
Typical Faults:
Overheating, low oil pressure, hard cold starting, exhaust smoke and reduced power
Manufacturer:
Yanmar - Japanese engine builder with long marine diesel experience
Engine Family:
6LY2 series high-output inline six marine diesel
Model Evolution:
Variants 6LY2-STE, 6LY2A-STP and 6LYA-STP cover turbocharged and aftercooled ratings
Production Location:
N/A - not stated in this manual
Production Years:
N/A - not stated in this manual
