Hydrofoil Stabilizer Fins – Fits Outboard Motors Up to 50HP (4-50 HP)

Hydrofoil Stabilizer Fins – Fits Outboard Motors Up to 50HP (4-50 HP)

These hydrofoil stabilizer fins are engineered for a universal fit on a wide range of outboard motors from 4 to 50 HP, including models from Mercury, Yamaha, Evinrude, Johnson, Honda, Tohatsu, and Suzuki. They are designed to improve performance by enabling quicker planing, reducing cavitation, and enhancing stability.

This product serves as a direct replacement for Five Oceans FO-4470 and can be used in similar applications as the SE Sport 300.

• Installation Method: Mounts directly to the anti-ventilation plate (cavitation plate) via a bolt-on process.
• Durable Construction: Molded from high-strength, UV-resistant black plastic for longevity.
• Complete Hardware Kit: Includes stainless steel screws, washers, and nuts for a secure installation.

Compatible Engine Models

Confirm your engine model/year in the table below. For Mercury owners, here’s a guide to help you identify your engine’s serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

Confirm your engine model/year in the table below. For Yamaha owners, here’s a guide to help you identify your engine’s serial/model: Yamaha Serial Number Guide. You can also review exploded diagrams to verify part numbers: Yamaha Parts Diagrams & Catalog.

Confirm your engine model/year in the table below. For Johnson/Evinrude owners, here’s a guide to help you identify your engine’s serial/model: Johnson Serial Number Guide.

Confirm your engine model/year in the table below. For Suzuki owners, You can review exploded diagrams here to verify part numbers: Suzuki Parts Diagrams & Catalog.

Confirm your engine model/year in the table below.

Technical Specifications

Package Contents

• 1 x Hydrofoil Set (Left and Right Fin)
• 4 x Stainless Steel Screws
• 4 x Washers
• 4 x Pressure Nuts

Installation Guide

1. Center the hydrofoil fins on the anti-ventilation (cavitation) plate of your outboard motor.
2. Ensure the fins are positioned correctly, then carefully mark the locations for the four mounting holes.
3. Important: Remove the fins and drill the four marked holes through the anti-ventilation plate.
4. Place the fins back onto the plate, aligning them with the newly drilled holes.
5. Insert the stainless steel screws with washers from the top and secure them from the bottom using the pressure nuts.
6. Tighten all four sets of hardware evenly and securely. Before using your boat, double-check that the fins are firmly attached.

Troubleshooting & FAQ

Q: How do I know if these fins will fit my outboard motor?

A: These hydrofoils are designed for a universal fit on most outboard motors from 4 to 50 HP. The key requirement is having an anti-ventilation (cavitation) plate wide enough to accommodate the fins, which measure approximately 180mm x 180mm (7.1" x 7.1") each. Installation requires drilling four holes into the plate.

Q: What is the benefit of a two-piece flexible design?

A: The two-piece design allows each foil to flex independently. This feature helps absorb and dissipate shock from wave impacts or underwater obstructions, reducing stress on the hydrofoils and the engine's lower unit.

Q: Do I need to be a mechanic to install these?

A: The bolt-on installation involves basic mechanical skills, including measuring, marking, and drilling. Many boat owners can perform the installation themselves. However, to ensure safety and correct placement, professional installation is always recommended.

Q: OEM vs. Aftermarket?

A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

Q: How fast do you ship and how much does it cost?

A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

Q: What is your warranty and return policy?

A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.