Stainless Steel Propellers for 4-6HP Mercury Engines

When choosing the right propeller for your 4-6 horsepower Mercury engine, you need to know what the important factors are that lead to the performance and lifespan. Not only does a right propeller maximize the performance of your engine, but it also improves fuel efficiency, handling, and overall boat ride. In this article, we are going to guide you through some of the top choices for these types of engines, such as the blade design, pitch, diameter, and OEM numbers so that you can make the best decision when it comes to replacing or upgrading your boat propeller.

Engine Compatibility and Propeller Selection

For boats powered by 4-6 horsepower engines, propeller selection is crucial to optimizing performance. These engines typically feature either 4-stroke or 2-stroke configurations, and the propeller must align with the engine’s specifications to maximize output and fuel efficiency. Let's take a look at the available options that are compatible with various 4-6HP Mercury engines.

1. Propeller for 4HP 4-Stroke Engines (1999 and Newer)

For those with 4HP 4-stroke engines manufactured from 1999 onward, a propeller with the right pitch and diameter is essential for achieving smooth cruising and steady acceleration. The recommended propeller for this engine type features:

• Blade Count (B): 3
• Diameter (D): 7.8 inches
• Pitch (P): 8 inches
• Rotation (R): Right-hand rotation

This design provides the perfect balance of thrust and maneuverability, allowing for an enhanced boating experience. With a 3-blade design, this propeller provides efficient propulsion while maintaining good grip on the water.

2. Propeller for 4HP 2-Stroke Engines (1987 and Newer)

The 4HP 2-stroke engine has been a popular choice for many recreational boaters since 1987. For these engines, the propeller must offer a higher pitch for a better balance between speed and torque. Here’s the specification for the ideal propeller:

• Blade Count (B): 3
• Diameter (D): 7.8 inches
• Pitch (P): 8 inches
• Rotation (R): Right-hand rotation

Similar to the 4-stroke version, the 3-blade configuration ensures that the engine operates at its peak efficiency, delivering power smoothly across a range of conditions. This setup is highly suitable for those looking for a reliable and durable propeller to pair with their 4HP 2-stroke engine.

3. Propeller for 5HP 2-Stroke Engines (1987 and Newer)

For the 5HP 2-stroke engine, which has also been in service since 1987, a propeller with a slightly larger diameter and pitch is recommended to match the engine’s enhanced power output. Here’s what you need to know:

• Blade Count (B): 3
• Diameter (D): 8.5 inches
• Pitch (P): 8.5 inches
• Rotation (R): Right-hand rotation

This propeller is designed to handle the increased torque produced by the 5HP engine. With a balanced pitch and diameter, it provides efficient propulsion while allowing the engine to achieve higher speeds without compromising performance or stability.

4. Propeller for 6HP 4-Stroke Engines (1999 and Newer)

The 6HP 4-stroke engine, which has been in use since 1999, is often favored for its reliability and quieter operation. For such an engine, the following propeller is the best match:

• Blade Count (B): 3
• Diameter (D): 8.5 inches
• Pitch (P): 8.5 inches
• Rotation (R): Right-hand rotation

With a slightly larger diameter and pitch, this propeller ensures that the 6HP engine performs at its best. The three-blade design offers better maneuverability and efficiency, especially for boats operating in calm to moderate conditions.

Material and Durability

All the propellers discussed here are made from high-quality stainless steel, a material that is known for its strength, corrosion resistance, and ability to withstand the harsh conditions of saltwater. Stainless steel propellers offer superior performance compared to their aluminum counterparts, providing greater durability and longevity, even after prolonged exposure to water. This makes them an excellent choice for those who require a robust, long-lasting solution for their 4-6HP Mercury engines.

OEM Number and Compatibility

Each propeller comes with a specific OEM number to ensure compatibility with your Mercury engine. The following OEM numbers correspond to the propellers discussed above:

• OEM# 48-812950A02: This propeller is designed for 4HP 4-stroke engines from 1999 onward, and for 4HP 2-stroke engines from 1987 onward. With a 7.8-inch diameter and an 8-inch pitch, this is the ideal match for these engine types.

• OEM# 48-897618A10: This propeller is intended for use with 5HP 2-stroke engines and 6HP 4-stroke engines. Featuring an 8.5-inch diameter and an 8.5-inch pitch, it ensures optimal performance and smooth operation.

These part numbers are your guide to selecting the correct propeller for your engine, ensuring that the propeller’s specifications match the engine’s requirements.

Conclusion

Choosing the right propeller is critical to ensuring that your 4-6HP Mercury engine performs at its peak. Whether you have a 4HP, 5HP, or 6HP engine, it’s essential to match the blade design, pitch, and diameter to your engine’s specifications. Stainless steel propellers offer unparalleled durability, making them a smart investment for boat owners who prioritize long-term performance.

While these propellers are not officially manufactured by Yamaha, they are perfectly suited for use with Yamaha engines, providing excellent compatibility and performance. Always consult the OEM part numbers to guarantee a perfect fit for your engine. With the right propeller, you can enjoy smoother, more efficient boating experiences for years to come.