Straight Screw Plug Kit – Fits Yamaha F9.9 to 300HP (Replaces 90340-08002-00, 90340-36002-00)
Straight Screw Plug Kit – Fits Yamaha F9.9 to 300HP (Replaces 90340-08002-00, 90340-36002-00) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
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Straight Screw Plug Kit – Fits Yamaha F9.9 to 300HP (Replaces 90340...
Straight Screw Plug Kit – Fits Yamaha F9.9 to 300HP (Replaces 90340-08002-00, 90340-36002-00) is backordered and will ship as soon as it is back in stock.
Product Details
This Straight Screw Plug Kit – Fits Yamaha Outboard F9.9 to 300HP (Replaces 90340-08002-00) is designed for a precise fit on a wide range of Yamaha outboard engines. It is compatible with models from F9.9 to 300HP, with options for both magnetic and non-magnetic screw types to suit your specific lower unit or gearcase needs.
This kit serves as a direct replacement for Yamaha part numbers 90340-08002-00 and 90340-36002-00, ensuring seamless interchangeability.
- Engineered for direct, threaded installation into the gearcase housing.
- Constructed from durable stainless steel for corrosion resistance in marine environments.
- Includes the essential gasket for a secure, leak-free seal upon installation.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yamaha | 90340-08002-00 |
| Yamaha | 90340-36002-00 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Yamaha engines, this plug fits a broad range of 4-stroke models. Verify your specific model is listed.
| Brand | Model | Rated HP | Stroke | OEM Part No. |
|---|---|---|---|---|
| Yamaha | Outboard | F9.9 | 4-Stroke | 90340-08002-00 |
| Yamaha | Outboard | F15 to F300 | 4-Stroke | 90340-08002-00 |
Technical Specs
- Product Type
- Straight Screw Plug Kit
- Installation
- Direct replacement, threaded installation
- Fuel Type
- Compatible with gasoline outboard engines
- Housing Material
- Stainless steel
- Other Technical Attributes
- Available in magnetic and non-magnetic variants
What’s in the Box
- 1 x Straight Screw Plug (90340-08002-00)
- 1 x Gasket (90430-08020-00)
Installation Notes
- Ensure the engine is turned off and secured in a tilted position to prevent oil spillage.
- Place a drain pan under the lower unit screw plug.
- Using an appropriate flathead screwdriver or socket, slowly loosen and remove the old screw plug.
- Clean the threads on the gearcase housing to remove any old sealant or debris.
- Place the new gasket on the new screw plug.
- Thread the new screw plug into the housing by hand to avoid cross-threading.
- Tighten the plug to the manufacturer's recommended torque specification. Do not overtighten.
- Check for leaks after running the engine.
Troubleshooting & FAQ
Will this plug fit my specific Yamaha engine model?
This kit is designed for a wide range of Yamaha 4-stroke outboards from F9.9 to 300HP. Please consult the compatibility table and verify your OEM part number (90340-08002-00) to ensure a perfect match.
Is this a magnetic or non-magnetic screw plug?
This product is available in both magnetic and non-magnetic variants. A magnetic plug can help capture fine metallic particles in the gear oil, providing an early indication of internal wear. The choice depends on user preference and service practices.
Why is replacing the gasket important?
The included gasket (90430-08020-00) is crucial for creating a watertight seal. Reusing an old, compressed gasket can lead to gear oil leaks and water intrusion, which can cause catastrophic gearcase failure.
How often should the screw plug and gasket be replaced?
It is best practice to replace the gasket with every gear oil change. The screw plug itself should be inspected for thread damage or corrosion and replaced as needed.
What are the signs that my old screw plug needs replacement?
Inspect your current plug for stripped threads, corrosion, or damage to the head that prevents proper tightening. If you notice any of these signs or persistent leaks despite a new gasket, the plug should be replaced.
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.
Payment & Security
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