Looking for the factory procedures to rebuild your marine diesel? All 234 pages of this Yanmar 6LY2-STE, 6LY2A-STP, 6LYA-STP service manual pdf (OEM #HINSI-H8-011-1) focus on getting your engine back to peak condition. You get full electrical wiring diagrams, detailed piping schematics, and step-by-step teardown instructions for the fuel injection pump and turbocharger. Open to the troubleshooting chapter to quickly trace faults in the cooling water system or reduction gear. Verify your fresh water pump impeller clearance sits between 0.3 and 1.1 mm, then step-torque the cylinder head bolts to a final 226 N·m. Don't risk a catastrophic engine failure out on the water. Download this bookmarked file, pull it up on your tablet in the engine room, and fix the problem right the first time.
What's Inside This Yanmar 6LY2-STE, 6LY2A-STP, 6LYA-STP Manual
| System | Pages | Key Topics |
|---|---|---|
| General | 6-26 | 1.Exterior Views, 2.Specifications, 3.Performance Curves, 4.Dimensions, 5.Wiring Diagrams, 6.Piping Diagrams |
| Inspection and Servicing of Basic Engine Parts | 27-57 | 1.Cylinder Block, 2.Cylinder Head, 3.Piston and Piston Pins, 4.Connecting Rod, 5.Crankshaft and Main Bearing, 6.Camshaft and Tappets, 7.Timing Gear, 8.Flywheel |
| Fuel Injection Equipment | 58-98 | Fuel Injection Pump Construction, Fuel Injection Pump Specifications, Fuel Supply System, Fuel Injection Nozzle, Fuel Feed Pump, Disassembly, Reassembly and Inspection of Governor |
| Turbocharger System | 99-118 | 1.Construction and Function, 2.Standards for Maintenance and Check, 3.Periodical Checking Procedure, 4.Disassembly Procedure, 5.Cleaning and Checking Procedure |
| Lubrication System | 119-128 | 1.Lubrication System, 2.Lube Oil Pump, 3.Lube Oil Filter, 4.Oil Pressure Control Valve, 5.Lube Oil Cooler, 6.Piston Cooling Nozzle, 7.Rotary Waste Oil Pump(Optional) |
| Cooling Water System | 129-143 | 1.Cooling Water System, 2.Sea Water Pump, 3.Fresh Water Pump, 4.Fresh Water Cooler, 5.Pressure Cap and Sub Tank, 6.Thermostat, 7.Kingston Cock(Optional) |
| Reduction and Reversing Gear | 144-154 | 1.Specification and System, 2.Readdembly and disassembly(KMH6A1), 3.Cautions for Reassembly |
| Remoto Control(Optional) | 155-157 | 1.Remoto Control System(Option), 2.Remoto Control Installation |
| Electrical System | 158-188 | 1.System Diagram, 2.Battery, 3.Starter Motor, 4.Alternator, 5.Instrument Panel, 6.Warning Devices, 7.Tachometer |
| Disassembly and Reassembly | 189-227 | 1.Disassembly and Reassembly Precautions, 2.Disassembly and Reassembly Tools, 3.Disassembly and Reassembly, 4.Main Parts Spec./ Tightening Torque, 5.Test Running |
| Troubleshooting | 228-233 | 1.Troubleshooting |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| All Models | ||
| Cylinder head bolt tightening torque (multi-step) | 118~177~226±10 N·m(kgf·m) | p. 226 |
| Intake valve seat angle | 120° | p. 33 |
| Exhaust valve seat angle | 90° | p. 33 |
| Fresh water pump impeller to pump body clearance (Standard) | 0.3~1.1 mm | p. 136 |
| Thermostat valve lift at full open | 8 mm | p. 141 |
| Delivery of seawater pump | ≧215 ℓ/min | p. 223 |
| Number of Cylinders | 6 | p. 1 |
| 6LY2-STE/6LY2A-STP | ||
| Nozzle tightening nut torque | 68.6~73.5 N·m (7.0~7.5 kgf·m) | p. 68 |
| 6LY2-STE | ||
| 6LY2-STE Max. Output at Crankshaft | 309(420)/3300 kw(hp)/rpm | p. 14 |
| 6LY2-STE Engine Lube Oil Capacity (Full/Effective) | 20.0 L / 8.0 L | p. 14 |
| 6LY2A-STP | ||
| 6LY2A-STP Fuel Stop Power (Flywheel Output) | 324/3300 kw/rpm | p. 15 |
| 6LYA-STP | ||
| 6LYA-STP Fuel Stop Power (Flywheel Output) | 272/3300 kw/rpm | p. 15 |
Yanmar 6LY2-STE, 6LY2A-STP, 6LYA-STP Common Problems This Manual Covers
Yanmar 6LY2A-STP catastrophic top end failure with sudden loss of compression and loud engine knocking sound p. 226
Remove the cylinder head and inspect the valves for damage. Verify the intake valve seat angle is exactly 120 degrees on page 33. When reassembling, torque the cylinder head bolts in multiple steps to 118, 177, and finally 226±10 N·m as specified on page 226.
Manual Section: Disassembly and ReassemblyEngine running hot under heavy load with repeated cooling water temperature alarm activation p. 136
Inspect the fresh water pump impeller for worn blades or corrosion. Measure the clearance between the impeller and the pump body. Replace the assembly if the gap exceeds the standard 0.3 to 1.1 mm tolerance found on page 136. Test the thermostat to ensure it opens at 71±2°C.
Manual Section: Cooling Water SystemProgressive rough idle and uneven cylinder output accompanied by upper valvetrain ticking noises p. 34
Check the valvetrain components for excessive wear. Measure the intake valve stem outside diameter using a micrometer. Replace the valve if it falls outside the standard φ8.960 to φ8.975 mm specification detailed on page 34. Inspect the exhaust valve seat sink depth, maintaining 0.2 to 0.4 mm.
Manual Section: Inspection and Servicing of Basic Engine PartsOil pressure warning lamp fails to extinguish while engine is running at operating temperature p. 233
Drain the oil and inspect the main bearings for excessive wear or scoring. Check the troubleshooting steps on page 233 for clogged strainers. When reinstalling the main bearing caps, torque the bolts to 25 to 27 kgf·m as shown on page 47 to maintain proper oil clearances.
Manual Section: TroubleshootingFrequently Asked Questions
What are the torque specifications for the cylinder head on a Yanmar 6LY2A-STP marine diesel engine?
For the 6LY2A-STP and 6LYA-STP models, the final tightening torque for the cylinder head bolts is specified as 216 to 236 N·m (22.0 to 24.0 kgf·m). This torque is applied after initial tightening steps to ensure proper sealing and assembly.
What are the replacement specifications for valves and valve train components on the Yanmar 6LY2-STE engine?
The manual specifies wear limits for key valve train components. For instance, the intake and exhaust valve stem outside diameter both have a wear limit of φ8.9 mm. The tappet stem outside diameter has a wear limit of φ14.17 mm, indicating when replacement is necessary.
What are the replacement specifications for cooling-system parts like the impeller and thermostat on the Yanmar 6LY2-STE engine?
The sea water pump impeller should be inspected for wear or damage and replaced periodically. The thermostat's opening temperature is 71°C, with a full open temperature of 85°C and a valve lift of 8 mm at full open. The seawater pump delivery should be at least 215 l/min.
What is the engine oil capacity for the Yanmar 6LY2A-STP and 6LYA-STP marine diesel engines?
For the 6LY2A-STP and 6LYA-STP models, the total engine oil capacity, including the oil filter, is 18 liters. The oil pan alone holds 16.4 liters, providing a clear measure for oil changes.
How quickly can I access this manual?
Instant PDF download. You get the full 234-page searchable Service Manual immediately after payment. Open it on your laptop, tablet, or phone right in the shop.
Are there any print restrictions on this Yanmar 6LY2-STE, 6LY2A-STP, 6LYA-STP?
The PDF is DRM-free. Print whatever sections you need to take out to the shop. Standard letter or A4 paper works.
Are hydraulic system diagrams in this Yanmar 6LY2-STE, 6LY2A-STP, 6LYA-STP?
Full hydraulic system diagrams are included, covering circuits, valve locations, and hydraulic component specs for the Yanmar 6LY2-STE, 6LY2A-STP, 6LYA-STP.
Document Quality
This document is a scanned PDF with an effective OCR layer, allowing you to search and copy the full text. The text quality is generally crisp and readable throughout the manual. Diagrams and illustrations are raster images, meaning they will pixelate when highly magnified, but their labels remain mostly legible. The pages are clean with minimal scan artifacts, and there are no significant stains, marks, or skewed pages. While there are no completely blank pages, some pages contain substantial empty space, especially at the end of sections.
Reviews
There are no reviews yet.