Part of the Yanmar Operator Manuals.
An air lock after a fuel filter change will keep a 4BY cranking all afternoon while the boat sits at the dock, and the bleeding procedure that clears it is in the Before You Operate section of this Yanmar operator manual. It covers the 4BY and 6BY marine diesels of the BY series, publication 0ABY0-G00100 from 2006, 127 pages in English as a PDF download.
Inside are the daily checks, fuel, oil, and coolant specifications, starting and shutdown procedures, and the periodic maintenance schedule these engines were built around: oil and filter changes, seawater pump belt inspection, zinc anodes, shift cable adjustment, and propeller shaft alignment. A troubleshooting section walks starting trouble, exhaust color, vibration, knocking, low power, and overheating back to their causes.
The file carries 131 bookmarks, so when the temperature gauge climbs you can jump straight to the overheat chart instead of paging through from the cover.
Complete the set for your 4BY, 6BY
- Repair Manual: Yanmar 6BY, 4BY Service Manual (incl. Wiring)
- Repair Manual: Yanmar 4BY, 6BY Marine Engines Service Manual (incl. Wiring)
Other edition of this manual
What's Inside This Operator Manual
| System | Pages | Key Topics |
|---|---|---|
| Introduction | 8-9 | Record of Ownership |
| Safety | 10-29 | During Operation and Maintenance |
| Product Overview | 30-39 | Yanmar BY-Series Features and Applications, Component Identification, Location of Label and Nameplates, Major Components, Fuses and Relays, Engine Cover |
| Before You Operate | 40-61 | Diesel Fuel, Engine Oil, Marine Gear or Stern Drive Oil, Engine Coolant, Power Steering Fluid Specifications, Daily Checks |
| Engine Operation | 62-69 | Starting the Engine, Shutting Down the Engine, Checking the Engine After Operation |
| Periodic Maintenance | 70-103 | After Initial 50 Hours of Operation (Change the Engine Oil and Replace the Engine Oil Filter, Check Shift Cable Adjustment, Adjust Propeller Shaft Alignment) |
| Troubleshooting | 104-113 | Starting Trouble, Exhaust Color, Vibration - Drive Disengaged, Vibration - Drive Engaged, Engine Knocks, Low Power Output, Engine Overheat, Engine Runs Cold |
| Long-Term Storage | 114-117 | Prepare Engine for Long-Term Storage |
| Specifications | 118-121 | Engine Specifications |
| EPA Warranty Usa Only | 122-127 | Yanmar Co., Ltd. Limited Emission Control System Warranty - Usa Only |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Inspection/Replacement Interval | Every 50 hours or monthly whichever comes first | p. 87 |
| Cleaning/Replacement Interval | Every 250 hours or one year whichever comes first | p. 87 |
| Torque | 25 N·m (18 ft-lb) | p. 93 |
