Fuel Pump Diaphragm Kit – Fits Yamaha 25–90 HP Outboards (Replaces 663-24411-00-00, 692-24411-00-00)
Fuel Pump Diaphragm Kit – Fits Yamaha 25–90 HP Outboards (Replaces 663-24411-00-00, 692-24411-00-00) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Fuel Pump Diaphragm Kit – Fits Yamaha 25–90 HP Outboards (Replaces ...
Product Details
This Fuel Pump Diaphragm Kit is designed for a wide range of Yamaha 25–90 HP 2-Stroke outboard motors manufactured between 1995 and 2009, including C-series models from 1995–2003. It provides the essential components to restore fuel pump performance and prevent leaks.
It serves as a direct replacement for Yamaha part numbers 663-24411-00-00 and 692-24411-00-00, and interchanges with Sierra 18-7391 and 18-7787.
- Engineered for direct-fit installation.
- Compatible with standard marine gasoline.
- Meets or exceeds OEM quality specifications for reliable performance.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yamaha | 663-24411-00-00 |
| Yamaha | 692-24411-00-00 |
| Sierra | 18-7391 |
| Sierra | 18-7787 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This kit is designed for select Yamaha 2-stroke models. Please verify your specific engine details.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yamaha | 40 | 40 | 2-Stroke | 1995–2006 | 692-24411-00 | |
| Yamaha | 50 | 50 | 2-Stroke | 1995–2009 | 692-24411-00 | |
| Yamaha | 60 | 60 | 2-Stroke | 2001–2006 | 692-24411-00 | |
| Yamaha | 70 | 70 | 2-Stroke | 1995–2009 | 692-24411-00 | |
| Yamaha | 90 | 90 | 2-Stroke | 1995–2009 | 692-24411-00 | |
| Yamaha | B90 | 90 | 2-Stroke | 1997–1999 | 692-24411-00 | |
| Yamaha | C25 | 25 | 2-Stroke | 1996–1997 | 692-24411-00 | |
| Yamaha | C30/C80 | 30/80 | 2-Stroke | 1996–1997 | 692-24411-00 | |
| Yamaha | C40 | 40 | 2-Stroke | 1995–2003 | 692-24411-00 | |
| Yamaha | C50 | 50 | 2-Stroke | 1998–2001 | 692-24411-00 | |
| Yamaha | C60 | 60 | 2-Stroke | 1996–2001 | 692-24411-00 | |
| Yamaha | C70 | 70 | 2-Stroke | 2000–2001 | 692-24411-00 | |
| Yamaha | C75 | 75 | 2-Stroke | 1995–1999 | 692-24411-00 |
Technical Specs
- Product Type
- Fuel Pump Diaphragm Kit
- Installation
- Direct replacement
- Fuel Type
- Gasoline
- Dimensions
- 4.0" H x 5.13" W x 1.13" L
What’s in the Box
- 1 x Diaphragm (Replaces 663-24411-00-00)
- 1 x Diaphragm (Replaces 692-24411-00-00)
- 1 x Gasket (Replaces 648-24435-02-00)
- 2 x Gasket (Replaces 648-24434-01-00)
Installation Notes
- Disconnect the battery and relieve fuel system pressure before beginning work. Ensure the work area is well-ventilated.
- Locate the fuel pump on the engine block and disconnect the fuel lines. Note their orientation for reassembly.
- Remove the bolts securing the fuel pump assembly and carefully detach it from the engine.
- Disassemble the fuel pump housing, taking care to note the order and orientation of diaphragms, gaskets, and springs.
- Clean all housing surfaces to remove old gasket material and debris.
- Install the new diaphragms and gaskets from the kit, ensuring they are correctly seated.
- Reassemble the fuel pump and mount it back onto the engine block. Torque bolts to manufacturer specifications.
- Reconnect fuel lines, reconnect the battery, and prime the fuel system. Check for leaks before starting the engine.
Troubleshooting & FAQ
How do I know if my fuel pump diaphragm is failing?
Common signs of a bad diaphragm include poor engine performance, stalling, difficulty starting, visible fuel leaks from the pump housing, or fuel mixing with engine oil (on applicable models).
Will this kit fit models outside the listed year ranges?
We can only guarantee fitment for the Yamaha models and years specified in the compatibility table. Using this kit on other models is not recommended, as internal pump designs can vary.
Is any special sealant needed for the gaskets?
No, these gaskets are designed to be installed dry. Ensure the mating surfaces on the fuel pump housing are clean, dry, and free of old gasket material for a proper seal.
What is the recommended replacement interval for a fuel pump diaphragm?
There is no fixed interval, but it is good practice to inspect the fuel system annually. We recommend replacing the diaphragm and gaskets every 500 hours or every 5 years of service, or immediately if you notice signs of wear or fuel leaks.
What is the difference between the two diaphragms included?
The two included diaphragms (equivalent to OEM parts 663-24411-00-00 and 692-24411-00-00) are for different layers within the fuel pump assembly. It is critical to match them to the correct position during reassembly.
Why are there two different gaskets included?
The kit includes two of one gasket type and one of another to match the different sealing points on the fuel pump assembly. Be sure to replace each old gasket with its corresponding new one.
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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