Straight Screw Plug Kit – Fits Yamaha Outboard F9.9 to 300HP (Replaces 90340-08002-00)

Straight Screw Plug Kit – Fits Yamaha Outboard F9.9 to 300HP (Replaces 90340-08002-00)

This straight screw plug kit is designed for a wide range of Yamaha outboard engines, serving as a reliable replacement for lower unit gear case drain or fill plugs. It ensures a secure seal to protect your engine's internal components.

This kit is a direct replacement for Yamaha part numbers 90340-08002-00 and 90340-36002-00. It is available in both magnetic and non-magnetic screw variants to suit your specific maintenance needs.

• Engine Compatibility: Fits Yamaha F9.9 to 300HP 4-Stroke models.
• Installation Method: Simple threaded installation for a secure fit.
• Package Includes: Each kit contains one screw plug and one gasket for a complete replacement.

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

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.

Technical Specifications

Package Contents

• 1 x Straight Screw Plug (Replaces 90340-08002-00)
• 1 x Gasket (Replaces 90430-08020-00)

Installation Guide

Follow these general steps to replace the screw plug. Always consult your engine's service manual for specific instructions.

1. Position a drain pan under the lower unit of your outboard engine.
2. Locate and identify the correct screw plug (drain or fill) that needs replacement.
3. Clean the area around the plug to prevent contaminants from entering the gear case.
4. Use a properly sized wrench to loosen and carefully remove the old screw plug.
5. Remove the old gasket and clean the sealing surface on the gear case.
6. Ensure the new gasket is properly seated on the new screw plug.
7. Thread the new plug in by hand to avoid cross-threading, then tighten it to the manufacturer's specified torque. Do not overtighten.
8. If draining fluid, refill the gear case with the recommended lubricant before tightening the fill plug.
9. After running the engine, check the plug for any signs of leaks.

Troubleshooting & FAQ

How do I confirm this plug fits my engine?
This plug is designed for a broad range of Yamaha 4-stroke outboards from F9.9 to F300 HP. The best way to confirm is by matching your old part number to 90340-08002-00 or 90340-36002-00. Always check the compatibility table and your engine's manual.

Should I choose the magnetic or non-magnetic version?
A magnetic plug can help capture fine metallic particles circulating in your gear oil, providing an early indicator of internal wear. The non-magnetic version functions as a standard plug. The choice depends on your preference for maintenance diagnostics.

Why is the included gasket important?
The gasket (90430-08020-00) is a critical component that creates a seal between the plug and the gear case. It is highly recommended to replace the gasket every time the plug is removed to prevent oil leaks and water intrusion.

OEM vs. Aftermarket?
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.

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

What is your warranty and return policy?
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.