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FLASHSALE26

Whale Tail Hydrofoil Stabilizer for 40–300 HP Outboard Motors and Stern Drives

Regular price $64.89

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Product Details

This marine-grade reinforced PA66 nylon Whale Tail Hydrofoil Stabilizer is designed for many 40–300 HP outboard motors and stern drives. By adding hydrodynamic lift at the stern, it can help improve low-speed handling, reduce porpoising, shorten time to plane, and help the boat remain on plane at lower speeds.

This is an aftermarket hydrofoil stabilizer referenced in some listings as a replacement for FO2003 and as a Whale Tail-style hydrofoil. Confirm the dimensions, mounting area, engine or drive configuration, and listed exceptions before ordering.

  • Drill-and-bolt installation on the anti-cavitation plate; mounting hardware and a drill bit are included.
  • Made from reinforced, marine-grade PA66 nylon for strength, impact resistance, and corrosion resistance.
  • The curved hydrofoil profile is intended to improve stern lift while helping manage drag and propeller-area turbulence.

Part Number References

The references below are aftermarket or listing references and should not be treated as proof of fitment by themselves. Always compare the product dimensions and application requirements with your equipment.

Reference Number or Description
Aftermarket reference FO2003
Product style Whale Tail Hydrofoil Stabilizer

Engine and Drive Compatibility

Application depends on the shape and available mounting area of the anti-cavitation plate or drive. The following information describes the intended application range and important exclusions noted for this style of hydrofoil; it does not replace a dimensional fit check.

Brand or Application Compatibility Notes
General application Many 40–300 HP outboard motors and stern drives Confirm clearance, mounting surface, dimensions, and hardware requirements before installation.
Volvo Penta SX-A, DPS, DPR, DPH, and 280/290 series applications may be suitable Some installations may require longer bolts and 1-inch fender washers. Not recommended for Volvo Ocean Series XDP applications.
Mercury Many 40–300 HP applications Not recommended for Mercury 4-Stroke 40, 50, or 60 HP models and not for Mercury Bravo II.
Honda Many 40–200 HP applications Not recommended for applications above 200 HP.
Yamaha Many 40–300 HP applications Not recommended for 350 HP applications.

Technical Specifications

Product Type
Hydrofoil stabilizer
Installation
Four-bolt installation; drilling required
Mounting Location
Anti-cavitation plate or compatible stern-drive mounting surface
Material
Reinforced PA66 nylon, marine-grade plastic
Color
Blue, silver, or red depending on the selected model or available version
Dimensions
Approximately 17 × 14.4 inches (432 × 366 mm)
Weight
Approximately 1.72 kg (3.79 lb)
Fitting Type
Drill and bolt
Hydrofoil Profile
Curved profile designed to provide stern lift and help reduce porpoising

What's in the Box

  • 1 × Hydrofoil stabilizer
  • 4 × Sets of stainless-steel screws, washers, and nuts
  • 1 × 6.5 mm drill bit
  • 1 × Installation instruction sheet

Installation Notes

  1. For safety, disconnect the engine battery before beginning installation.
  2. Center the hydrofoil on the anti-cavitation plate or compatible drive mounting surface. Position it as far back as practical without interfering with propeller movement or steering components.
  3. Use the hydrofoil mounting holes as a template and mark the four drilling points.
  4. Remove the hydrofoil and carefully drill the marked holes with the included 6.5 mm drill bit, provided the plate thickness and material are suitable for drilling.
  5. Place the hydrofoil on the plate and align it with the drilled holes.
  6. Insert the stainless-steel bolts from the top and secure them underneath with the washers and nuts.
  7. Tighten the fasteners evenly and securely. Do not overtighten, as this may damage the plate or the hydrofoil.
  8. Reconnect the battery and test the boat at low speed in a safe, open-water area. Check the installation again after the initial test run.

Troubleshooting and FAQ

Will this hydrofoil fit my specific engine or drive?

This stabilizer is intended for many 40–300 HP outboard motors and stern drives, but fitment depends on the plate or drive geometry, available mounting area, clearance, and the exclusions listed above. Compare the dimensions and installation requirements with your equipment before ordering.

Do I have to drill holes in the anti-cavitation plate?

Yes. This model uses a four-bolt installation and requires four holes to be drilled in a suitable mounting surface. If you are not certain that the plate can be drilled safely, consult a qualified marine technician.

How can a hydrofoil improve performance?

The hydrofoil adds hydrodynamic lift to the stern. Depending on the boat and setup, this may help the boat reach plane sooner, stay on plane at lower speeds, improve low-speed handling, and reduce bow bouncing or porpoising.

Will this reduce my boat's top speed?

Results vary by boat, engine, propeller, loading, and installation. A hydrofoil may change handling and speed characteristics, and some setups may experience a small reduction in top speed because of added drag. Test the boat carefully after installation.

What is the benefit of reinforced PA66 nylon?

Reinforced PA66 nylon combines stiffness, impact resistance, and corrosion resistance. It is intended to provide a durable alternative to ordinary unreinforced plastic in a marine environment.

Is this an OEM part?

No. This listing is for an aftermarket hydrofoil stabilizer. The FO2003 reference is provided as an aftermarket reference only and does not, by itself, establish OEM manufacture or universal interchangeability.

How should I confirm fitment before ordering?

Check the available mounting area, overall dimensions, anti-cavitation plate or drive shape, propeller and steering clearance, engine horsepower, and the model-specific exclusions. If any measurement or application detail differs, do not proceed without professional confirmation.

Safety and Important Information

  • Verify the dimensions, mounting surface, clearances, and application notes against your equipment before purchase.
  • This product requires drilling and bolting; professional marine installation is recommended when you are not experienced with structural or engine-related work.
  • Inspect all fasteners and the hydrofoil after the first test run and periodically during use.
  • Do not operate the boat if the hydrofoil is loose, cracked, damaged, or interfering with the propeller, steering, or trim system.
  • This is an aftermarket replacement product, not an OEM component.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts selected for dependable materials and real-world use.
  • Manufacturer-Direct Value — We aim to provide practical replacement solutions with clear product information.
  • Support-Focused Service — Confirm your application details before ordering and contact support if you need help reviewing product measurements or installation requirements.

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