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General| Horsepower | 25 hp |
|---|---|
| Gear Ratio | 2.08:1 |
| Full Throttle RPM Range | 4500 - 5500 rpm |
| Fuel System | Carburetor |
| Displacement | 496 cc |
| Fuel Type | Gasoline |
| Starting System | Manual |
| Cooling System | Water |
| Bore x Stroke | 68 mm x 68 mm |
| Fuel Tank Capacity | External tank |
| Engine Type | 2-cylinder, 2-stroke |
Explains the sequential step-by-step format for procedures and the use of symbols for component conditions and actions.
Describes that illustrations represent all designated models and cross-references are minimized.
Explains the meaning of Safety Alert, WARNING, CAUTION, and NOTE symbols used in the manual.
Symbols 1 to 9 indicate chapter content (e.g., General Information, Specifications, Trouble Analysis).
Symbols 0 to E indicate specific data like Special tool, Specified liquid, Specified engine speed, Specified torque, etc.
Symbols F to H indicate lubricant grade and location; Symbols I to N indicate sealing agent grade and application point.
Details on identifying the outboard motor's serial number and starting serial numbers for various models.
Provides essential safety procedures including fire prevention, ventilation, self-protection, and proper use of oils and greases.
Lists and illustrates special tools required for maintenance, including measuring tools and removal/installation tools.
Provides detailed specifications for dimensions, weight, performance, and power unit for various models.
Details maintenance specifications for engine components like cylinder head, pistons, crankshaft, and connecting rods.
Provides maintenance specifications for the lower unit, including gear backlash and propeller details.
Lists specified tightening torques for standard fasteners across different units like Power Unit, Lower Unit, Bracket, PTT Unit, and Electrical.
Outlines checks and procedures to be performed before delivery of the outboard motor.
Provides a chart detailing maintenance intervals for various components based on hours or time.
Details inspection procedures for the battery, including checking fluid level, specific gravity, and warnings.
Describes procedures for inspecting and adjusting carburetor components like fuel enrichment valve and linkage.
Covers checks for spark gap, peak voltage of ignition system components, spark plugs, and engine stop switch.
Details checks for starter motor, battery, fuse, starter relay, starter switch, neutral switch, and fuel enrichment valve.
Explains how to measure peak voltage for the rectifier and lighting coil, with troubleshooting guidance.
Details inspection and checks for the PTT unit, including motor operation, fluid level, and trim sensor.
Provides an exploded view of the fuel system components including carburetor, fuel filter, and fuel joints.
Details the procedure for removing, cleaning, and inspecting the fuel line and filter.
Describes visual inspection of carburetor body, needle valve, pilot screw, collar, and float for wear or damage.
Presents an exploded view of the power unit components with part numbers.
Covers cleaning the engine, checking tools and equipment before commencing removal and disassembly.
Details the disassembly steps for components like cylinder head, crankcase, crankshaft, and pistons.
Explains how to clean and inspect the cylinder head for warping, cracks, and carbon deposits.
Guides on cleaning and measuring piston diameter and clearance, including steps for oversize pistons.
Provides an exploded view of the lower unit with numbered parts.
Details procedures for removing and disassembling the lower unit components like propeller, gear case, and water pump.
Explains inspection steps for gear case, bearing housing, claw-washer, ring-nut, water pump housing, gears, and bearings.
Covers assembly and adjustment procedures, including shim selection and backlash measurement for forward and reverse gears.
Presents an exploded view of the steering handle assembly with parts and removal/installation chart.
Provides an exploded view of the bottom cowling with parts and removal/installation chart.
Presents an exploded view of the upper case assembly with parts and removal/installation chart.
Details service points for the PTT unit, including motor inspection and assembly.
Covers exploded diagrams and removal/installation charts for clamp brackets (except PTT model and PTT model).
Provides critical service points for tilt rod removal and installation, including warnings and notes.
Illustrates and lists electrical components for various models (25JMH, 25JMHO, etc.).
Provides wiring diagrams and wire color codes for different model groups (25JEO, 30DMO, etc.).
Details the procedures for removing and installing the flywheel magneto, including necessary tools and cautions.
Explains how to inspect electrical systems using a digital circuit tester, including peak voltage measurements.
Covers checks for spark gap, peak voltage of ignition system components, spark plugs, and engine stop switch.
Details checks for starter motor, battery, fuse, starter relay, starter switch, neutral switch, and fuel enrichment valve.
Explains how to measure peak voltage for the rectifier and lighting coil, with troubleshooting guidance.
Details inspection and checks for the PTT unit, including motor operation, fluid level, and trim sensor.
Lists common troubleshooting items to check before consulting the chart.
A comprehensive chart correlating trouble modes with check elements and reference chapters.
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