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Propeller Nut Kit – Fits Suzuki 40-65 HP Outboards (Replaces 57630-94300, 57630-94301)

Regular price $24.94
Shipping calculated at checkout.

Worry-free returns

You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.

Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This aftermarket Propeller Nut Kit is designed for a broad range of Suzuki 40-65 HP outboard engines, including both 2-stroke and 4-stroke models manufactured from 1986 to 2022. It provides all the necessary hardware to securely fasten a propeller.

This kit serves as a direct replacement for Sierra 18-3777 and Suzuki OEM part numbers 57630-94300 and 57630-94301.

  • Engineered for direct replacement installation.
  • Constructed from premium quality materials to meet or exceed OEM specifications.
  • Includes the essential prop nut, cotter pin, washer, and spacer.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand Part Number
Sierra 18-3777
Suzuki 57630-94300
Suzuki 57630-94301

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Brand Model Rated HP Stroke Years OEM Part No. Notes
Suzuki DF40 40 4-Stroke 1999–2010 57630-94300/94301
Suzuki DF50 50 4-Stroke 1999–2010 57630-94300/94301
Suzuki DF40A 40 4-Stroke 2010–2022 57630-94300/94301
Suzuki DF50A 50 4-Stroke 2010–2022 57630-94300/94301
Suzuki DF60A 60 4-Stroke 2010–2022 57630-94300/94301
Suzuki DT40C 40 2-Stroke 1986–1999 57630-94300/94301
Suzuki DT40W 40 2-Stroke 2001–2004 57630-94300/94301 K1-K4 series
Suzuki DT55 55 2-Stroke 1988–1999 57630-94300/94301 J-X series
Suzuki DT65 65 2-Stroke 1988–1999 57630-94300/94301 J-X series

Technical Specs

Product Type
Propeller Hardware Kit
Installation
Direct replacement
Fitting Type
Propeller nut assembly
Dimensions
Height: 7.13; Width: 6.0; Length: 1.75;
Warranty
Limited lifetime (Sierra brand)
Other Technical Attributes
Premium quality material; Meets or exceeds OEM specifications

What’s in the Box

  • 1 x Prop Nut (18-3726/09141-18005)
  • 1 x Cotter Pin (18-3735)
  • 1 x Washer (09160-18028)
  • 1 x Spacer (57633-94300)

Installation Notes

  1. Ensure the engine is in neutral and the ignition is off. For safety, disconnect the battery.
  2. Remove the old cotter pin, propeller nut, washer, and spacer. Take note of their order.
  3. Clean the propeller shaft threads and inspect for any damage or wear.
  4. Slide the new spacer onto the shaft first, followed by the propeller.
  5. Place the new washer on the shaft, ensuring it sits flat against the propeller hub.
  6. Thread the new propeller nut onto the shaft and tighten it to the manufacturer's recommended torque specification. Do not overtighten.
  7. Align the castellations on the nut with the hole in the propeller shaft.
  8. Insert the new cotter pin through the hole and bend the ends to secure it in place.

Troubleshooting & FAQ

How do I know if this propeller nut kit will fit my specific Suzuki model?

This kit is designed for Suzuki 40-65 HP outboards from 1986–2022. The best way to confirm fitment is to check the "Engine & Model Compatibility" table on this page. If your engine model and year are listed, it will fit. You can also cross-reference your old part number with the ones provided in our "Part Number Matrix."

What torque should I use to tighten the propeller nut?

Always refer to your engine's specific service manual for the correct torque specification. Overtightening can damage the propeller shaft or hub, while under-tightening can cause the propeller to come loose.

What are the signs that my current propeller nut or hardware needs replacement?

Look for visible signs of corrosion, stripped threads on the nut, or a damaged or missing cotter pin. If you notice increased vibration during operation or hear an unusual noise from the propeller area, inspect the hardware immediately. It is good practice to inspect the hardware every time you remove the propeller.

Is it necessary to replace the cotter pin every time?

Yes. The cotter pin is a critical single-use safety component designed to prevent the propeller nut from loosening. Always use a new cotter pin upon reinstallation to ensure a secure fit.

What is the difference between this aftermarket kit and the original Suzuki OEM parts?

This aftermarket kit is designed to meet or exceed OEM specifications for fit, form, and function. It is made from high-quality, corrosion-resistant materials comparable to the original parts but is available at a more competitive price point.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

  • Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
  • This is an aftermarket replacement, not an OEM component.
  • Professional installation is recommended for safety and performance.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
  • Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
  • Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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