Ignition Key Switch – Fits Yamaha Outboards 6–300 HP (Replaces 703-82510-43-00, 703-82510-42-00, 703-82510-44-00, Sierra MP51040)
Ignition Key Switch – Fits Yamaha Outboards 6–300 HP (Replaces 703-82510-43-00, 703-82510-42-00, 703-82510-44-00, Sierra MP51040) 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.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
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Ignition Key Switch – Fits Yamaha Outboards 6–300 HP (Replaces 703-...
Ignition Key Switch – Fits Yamaha Outboards 6–300 HP (Replaces 703-82510-43-00, 703-82510-42-00, 703-82510-44-00, Sierra MP51040) is backordered and will ship as soon as it is back in stock.
Product Details
This is a replacement Yamaha Ignition Key Switch assembly designed for a wide range of Yamaha outboards from 6 HP to 300 HP, including both 2-stroke and 4-stroke models manufactured between 1998 and 2013. It features a push-to-choke function integrated into the panel-mount design.
It serves as a direct interchange for Yamaha part numbers 703-82510-43-00, 703-82510-42-00, and 703-82510-44-00, as well as Sierra Marine part MP51040.
- Durable Construction: Built with a high-strength polyoxymethylene housing and copper core, fully sealed to be waterproof, dustproof, and insulated.
- Simple Installation: Connects directly to the original cable harness without requiring special tools.
- Push-to-Choke Functionality: The key can be pushed in to activate the engine choke for cold starts.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yamaha | 703-82510-43-00 |
| Yamaha | 703-82510-42-00 |
| Yamaha | 703-82510-44-00 |
| Sierra | MP51040 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This ignition switch fits a broad array of international and domestic Yamaha outboard models produced from 1998–2013.
| Brand | Model | Rated HP | Years | OEM Part No. |
|---|---|---|---|---|
| Yamaha | Outboard | 225, 250 | 2003 | 703-82510-43-00 |
| Yamaha | International | 6 | 2000–2001 | 703-82510-43-00 |
| Yamaha | International | 8 | 2000–2012 | 703-82510-43-00 |
| Yamaha | International | 9.9 | 2001–2013 | 703-82510-43-00 |
| Yamaha | International | 13.5 | 2005–2007 | 703-82510-43-00 |
| Yamaha | International | 15 | 2001–2007 | 703-82510-43-00 |
| Yamaha | International | 25 | 1999 | 703-82510-43-00 |
| Yamaha | International | 30 | 1999–2012 | 703-82510-43-00 |
| Yamaha | International | 40 | 1998–2012 | 703-82510-43-00 |
| Yamaha | International | 48 | 2003 | 703-82510-43-00 |
| Yamaha | International | 50 | 1999–2012 | 703-82510-43-00 |
| Yamaha | International | 55 | 2000–2006, 2008 | 703-82510-43-00 |
| Yamaha | International | 60 | 1999–2012 | 703-82510-43-00 |
| Yamaha | International | 70 | 2000–2012 | 703-82510-43-00 |
| Yamaha | International | 75 | 1999–2012 | 703-82510-43-00 |
| Yamaha | International | 80 | 2000–2008 | 703-82510-43-00 |
| Yamaha | International | 85 | 1999–2012 | 703-82510-43-00 |
| Yamaha | International | 90 | 2000–2012 | 703-82510-43-00 |
| Yamaha | International | 95 | 2005–2008 | 703-82510-43-00 |
| Yamaha | International | 100 | 2000–2006, 2008, 2011 | 703-82510-43-00 |
| Yamaha | International | 115 | 1999–2012 | 703-82510-43-00 |
| Yamaha | International | 130 | 2000–2007 | 703-82510-43-00 |
| Yamaha | International | 140 | 2001–2012 | 703-82510-43-00 |
| Yamaha | International | 150 | 1999–2012 | 703-82510-43-00 |
| Yamaha | International | 175 | 1999–2012 | 703-82510-43-00 |
| Yamaha | International | 200 | 1999–2013 | 703-82510-43-00 |
| Yamaha | International | 225 | 1999–2011 | 703-82510-43-00 |
| Yamaha | International | 240 | 2005–2007 | 703-82510-43-00 |
| Yamaha | International | 250 | 2001–2012 | 703-82510-43-00 |
| Yamaha | International | 300 | 2004–2007 | 703-82510-43-00 |
| Yamaha | International | VMAX | 2002–2013 | 703-82510-43-00 |
Technical Specs
- Product Type
- Ignition Main Key Switch Assembly
- Installation
- Panel Mount with Push to Choke
- Operation Mode
- ON-OFF-START
- Current Rating
- 12 Amps
- Operating Voltage
- 12 Volts DC
- Contact Type
- Normally Closed
- Connector Type
- Plug In
- Housing Material
- High-Strength Polyoxymethylene with Copper Core
- Construction
- Sealed Glue Process (Waterproof, Dustproof, Insulated)
- Installation Method
- Cable Connection (No Tools Required)
- Circuit Type
- 3-way
- Contact Material
- Copper
What’s in the Box
- 1 x Ignition Key Switch Assembly (Push to Choke)
Installation Notes
- Safety First: Ensure the engine is off and disconnect the boat's battery before beginning work.
- Access the Panel: Gain access to the back of the console or panel where the existing ignition switch is mounted.
- Disconnect: Carefully unplug the wiring harness connector from the back of the old switch assembly.
- Remove Old Switch: Unscrew the retaining nut on the front of the panel and remove the old switch.
- Install New Switch: Insert the new ignition switch into the panel, align it correctly, and tighten the retaining nut until snug.
- Reconnect: Plug the original wiring harness firmly into the connector on the new switch until it clicks into place.
- Test: Reconnect the battery. Test all key positions (OFF, ON, START) and the push-to-choke function to ensure proper operation before heading out on the water.
Troubleshooting & FAQ
Does this ignition switch work for both 2-stroke and 4-stroke engines?
Yes, this switch is confirmed to be compatible with both 2-stroke and 4-stroke Yamaha outboard engines within the specified horsepower and year ranges.
How does the "Push to Choke" feature work?
When the key is in the ON position (before starting), you can push the key inwards to activate the engine's choke circuit. This helps provide a richer fuel mixture for easier cold starts. Release the key once the engine starts to warm up.
What are the signs my old ignition switch is failing?
Common signs include difficulty turning the key, the engine not cranking when the key is turned to START, intermittent power loss to gauges, or the engine shutting off unexpectedly. Corrosion on the terminals is also a clear indicator.
Is this a direct plug-and-play replacement?
Yes, this assembly is designed to connect directly to the original factory wiring harness connector without any modification or splicing required.
My engine model isn’t listed, but the part number matches. Will it fit?
If your old part has one of the cross-referenced part numbers (e.g., 703-82510-43-00), this switch should be a compatible replacement. However, always verify by comparing our product photos against your original part to be certain.
What is the difference between an OEM and an aftermarket part?
This listing is for an aftermarket replacement, not an original equipment manufacturer (OEM) part. It has been engineered to meet or exceed OEM-level specifications using comparable, high-quality materials. Our parts are manufactured in an ISO 9002 certified facility and are batch-inspected for quality and consistency.
What are the shipping speed and cost?
We ship worldwide quickly, with typical transit times of 5–15 days for most regions. Standard shipping is free. Expedited shipping options, if available for your location, will be presented at checkout.
What is the warranty and return policy?
This product is covered by a 1-year warranty against manufacturing defects under normal marine use. Should an issue arise, please contact our support team with your order details. Returns are accepted within our standard return window for items that are unused and in their original condition. You can see our full policy page or reach out for specific 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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