Johnson 10R78M 9.9HP – 2S (M17254)

Johnson 10R78M 9.9HP – 2-Stroke (M17254) is a lightweight, portable outboard motor well-suited for small boats, dinghies, and fishing vessels. As part of Johnson’s reliable 2-stroke engine lineup, this model is known for its simplicity, durability, and responsive performance. Its compact size and manageable weight make it an excellent choice for boaters looking for efficient and easy-to-maintain power.

Specifications:

• Engine Type: 2-Stroke, 2-cylinder.
• Horsepower: 9.9 HP.
• Year Model: 1978 (based on the model number suffix “78”).
• Starting System: Manual pull start for simple and effective ignition.
• Control Type: Tiller handle for direct control over throttle and steering.
• Shaft Length: Short shaft (15 inches), ideal for boats with lower transoms.
• Fuel Delivery: Carbureted, ensuring straightforward and reliable operation.

Performance and Features:

• Weight: Approximately 74 lbs (34 kg), making it lightweight and portable for easy handling.
• Fuel System: Operates on a pre-mixed fuel/oil ratio (typically 50:1, though this should be confirmed in the owner’s manual for the specific model year).
• Cooling System: Water-cooled to maintain optimal operating temperatures and improve engine longevity.
• Ignition System: Magneto ignition for dependable starting and consistent performance.
• Gear Shifting: Forward, Neutral, and Reverse gears for flexible maneuvering.
• Propeller: Typically equipped with an aluminum propeller, with replacement options available for specific boating needs.

Applications:

Johnson 10R78M 9.9HP – 2-Stroke is ideal for:

• Fishing boats: A great match for lightweight fishing boats and skiffs.
• Dinghies and inflatables: Perfect for small tenders or inflatable crafts due to its compact size.
• Portable power: Easy to transport and install on various small boats.
• Utility tasks: Suitable for general small boat use, including light towing or transport.

Maintenance and Care:

• Fuel: Use a high-quality 2-stroke oil mixed with gasoline at the recommended ratio (typically 50:1). Fresh fuel is critical for optimal performance.
• Routine Maintenance: Regularly clean the carburetor, inspect and replace spark plugs as needed, check the water pump, and monitor for signs of corrosion or wear.
• Winterization: Drain the fuel system, fog the engine to prevent corrosion, and store it in a dry, secure location.

Advantages of the Johnson 9.9HP 2-Stroke:

• Lightweight and Portable: Easy to transport and mount, making it versatile for different applications.
• Responsive Performance: Quick throttle response and reliable power for small boats.
• Simple Maintenance: Straightforward design makes it easier to maintain compared to more complex modern outboards.
• Durable Construction: Built to withstand tough marine conditions, ensuring a long service life with proper care. Johnson 10R78M 9.9HP -2S (M17254)