ARCO 3451 Replacement Starter – Fits Yamaha Outboards 300-425 HP (Replaces 6AW-81800-00-00)
ARCO 3451 Replacement Starter – Fits Yamaha Outboards 300-425 HP (Replaces 6AW-81800-00-00) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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.).
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
ARCO 3451 Replacement Starter – Fits Yamaha Outboards 300-425 HP (R...
Product Details
This high-quality ARCO 3451 Replacement Starter is designed for Yamaha 4-stroke outboard engines from 300 HP to 425 HP, covering models from 2007 to 2022. It is engineered to fit F/LF series 300 HP engines (2007–2009) and all 350-425 HP models within the specified years.
It serves as a direct replacement for Yamaha part 6AW-81800-00-00 and interchanges with Mitsubishi M008T71771, M008T71772, and Sierra 18-55507.
- Engineered for direct OEM replacement installation.
- Features enhanced corrosion resistance with a nickel-coated and epoxy-painted housing.
- Designed to minimize water intrusion for long service life in marine environments.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yamaha | 6AW-81800-00-00 |
| Mitsubishi | M008T71771 |
| Mitsubishi | M008T71772 |
| Sierra | 18-55507 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This starter fits a wide range of Yamaha 4-stroke outboards from 300 to 425 HP.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yamaha | F300TUR | 300 | 4-Stroke | 2007–2009 | 6AW-81800-00-00 | |
| Yamaha | F300TXR | 300 | 4-Stroke | 2007–2009 | 6AW-81800-00-00 | |
| Yamaha | LF300TUR | 300 | 4-Stroke | 2007–2009 | 6AW-81800-00-00 | |
| Yamaha | LF300TXR | 300 | 4-Stroke | 2007–2009 | 6AW-81800-00-00 | |
| Yamaha | F350TUR | 350 | 4-Stroke | 2007–2009 | 6AW-81800-00-00 | |
| Yamaha | F350TXR | 350 | 4-Stroke | 2007–2009 | 6AW-81800-00-00 | |
| Yamaha | LF350TUR | 350 | 4-Stroke | 2007–2009 | 6AW-81800-00-00 | |
| Yamaha | LF350TXR | 350 | 4-Stroke | 2007–2009 | 6AW-81800-00-00 | |
| Yamaha | F350UCA/XCA | 350 | 4-Stroke | 2010–2011 | 6AW-81800-00-00 | |
| Yamaha | LF350UCA/XCA | 350 | 4-Stroke | 2010–2011 | 6AW-81800-00-00 | |
| Yamaha | F350UCB/XCB | 350 | 4-Stroke | 2012–2015 | 6AW-81800-00-00 | |
| Yamaha | LF350UCB/XCB | 350 | 4-Stroke | 2012–2015 | 6AW-81800-00-00 | |
| Yamaha | F350NCB | 350 | 4-Stroke | 2014–2015 | 6AW-81800-00-00 | |
| Yamaha | F350NCC/XCC | 350 | 4-Stroke | 2016–2019 | 6AW-81800-00-00 | |
| Yamaha | F350UCC | 350 | 4-Stroke | 2016–2019 | 6AW-81800-00-00 | |
| Yamaha | LF350UCC/XCC | 350 | 4-Stroke | 2016–2019 | 6AW-81800-00-00 | |
| Yamaha | F350AET1U/X | 350 | 4-Stroke | 2010 | 6AW-81800-00-00 | |
| Yamaha | FL350AET1U/X | 350 | 4-Stroke | 2010 | 6AW-81800-00-00 | |
| Yamaha | XF425NSA/NSA2/NSA7 | 425 | 4-Stroke | 2018–2020 | 6AW-81800-00-00 | |
| Yamaha | XF425NSB/NSB2/NSB7 | 425 | 4-Stroke | 2020–2022 | 6AW-81800-00-00 |
Technical Specs
- Product Type
- Outboard Engine Starter Motor
- Installation
- Direct OEM replacement
- Voltage
- 12 Volts
- Housing Material
- Metal with nickel coating/epoxy paint
- Product Dimensions
- 15.0" L x 10.0" W x 10.0" H
- Insulation Rating
- Tested to withstand 50 times operating voltages
- Corrosion Resistance
- Enhanced (nickel coated/epoxy painted)
- Water Intrusion
- Minimized design
- Performance
- Designed for long life and optimum performance
What’s in the Box
- 1 x Starter Motor Assembly (ARCO 3451)
Installation Notes
- Disconnect the negative battery cable to prevent electrical shorts.
- Identify and label all electrical wires connected to the old starter motor for correct reassembly.
- Carefully remove the electrical connections from the starter terminals.
- Unbolt and remove the old starter motor from the engine block.
- Visually compare the new starter with the old one to confirm an identical match in size, mounting points, and gear.
- Mount the new starter motor, ensuring it is flush against the engine block. Hand-tighten the mounting bolts first, then torque them to the manufacturer's specified values.
- Reconnect the electrical wiring to the correct terminals on the new starter as labeled earlier. Ensure all connections are secure.
- Reconnect the negative battery cable.
- Test the new starter by starting the engine. Listen for smooth engagement and proper operation.
Troubleshooting & FAQ
How do I know if this starter fits my engine?
This starter fits specific Yamaha 300-425 HP 4-stroke models from 2007–2022. Please check the "Engine & Model Compatibility" table on this page with your engine's model and year to confirm fitment.
What are the signs of a failing starter motor?
Common signs include a clicking sound when you turn the key, the engine turning over slowly, intermittent starting, or no response at all. Grinding noises can also indicate a problem with the starter or flywheel.
Is this a direct replacement for the Yamaha 6AW-81800-00-00?
Yes, this ARCO 3451 is designed as a direct, bolt-on replacement for the OEM Yamaha part 6AW-81800-00-00, requiring no modifications for installation.
What is the difference between this starter and the OEM version?
This is an aftermarket part built to meet or exceed original equipment specifications for performance and durability. It features enhanced corrosion resistance but is offered at a more competitive price point than the OEM part.
Can I install this starter myself?
While installation is straightforward for those with mechanical experience, we recommend professional installation to ensure safety, proper torque on all fasteners, and correct electrical connections.
How often should a starter motor be replaced?
There is no fixed replacement interval for a starter. It should be replaced when it shows signs of failure. Its lifespan depends on usage, environmental conditions (especially saltwater exposure), and battery health.
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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