Charging Coil - Fits Yamaha 2-Stroke 40HP Outboard Motors (Replaces 66T-85520-00)
Charging Coil - Fits Yamaha 2-Stroke 40HP Outboard Motors (Replaces 66T-85520-00) 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.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Charging Coil - Fits Yamaha 2-Stroke 40HP Outboard Motors (Replaces...
Product Details
This aftermarket Charging Coil – Fits Yamaha 2-Stroke 40HP Outboard Motors (Replaces 66T-85520-00) is engineered for specific Yamaha 2-Stroke 40HP E40X and 40X M(W/T)HS/L outboard models manufactured between 1998 and 2017.
It serves as a direct cross-reference for Yamaha part numbers 66T-85520-00-00, 66T-85520-00, and 66T-85520.
- Features a simple plug-and-play harness for direct replacement.
- Constructed with highest-grade copper windings for durability and performance.
- Designed to operate in high-temperature marine environments up to 200°C (392°F).
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yamaha | 66T-85520-00-00 |
| Yamaha | 66T-85520-00 |
| Yamaha | 66T-85520 |
Engine & Model Compatibility
Confirm your engine model and year in the table below.
This coil is a direct fit for the following Yamaha outboard models.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. |
|---|---|---|---|---|---|
| Yamaha | 40X M(W/T)HS/L | 40 | 2-Stroke | 1998–2013 | 66T-85520-00-00 |
| Yamaha | E40X M(W/T)HS/L | 40 | 2-Stroke | 1999–2009 | 66T-85520-00-00 |
| Yamaha | E40X MHL | 40 | 2-Stroke | 2010–2017 | 66T-85520-00-00 |
Technical Specs
- Product Type
- Charge Coil Assembly
- Installation
- Direct replacement, plug-and-play
- Fuel Type
- Gasoline
- Connection
- Wire harness with connector
- Housing Material
- Metal
- Housing Color
- Black
- Product Dimensions
- Height: 4.5 in; Width: 6.0 in; Length: 10.0 in
- Weight
- 0.380 kg (0.84 lb)
- Operating Temperature
- Up to 200°C (392°F)
- Warranty
- 1 Year
- Technical Attributes
- Generator stator coil type; highest grade copper windings
What’s in the Box
- 1 x Charge Coil Assembly (66T-85520-00-00)
Installation Notes
- Disconnect the battery terminals to prevent electrical hazards.
- Locate and access the existing charging coil on the engine.
- Carefully disconnect the wire harness connector from the old coil.
- Unbolt and remove the old charging coil assembly.
- Mount the new coil assembly, ensuring it is securely fastened.
- Connect the new coil's wire harness plug to the engine's electrical system.
- Reconnect the battery terminals.
- Start the engine and test the charging system to confirm proper operation.
Troubleshooting & FAQ
How do I know if this charging coil fits my motor?
Verify that your engine's model, horsepower, and year fall within the ranges specified in the "Engine & Model Compatibility" table. Also, visually compare the product photos and part numbers to your original coil before ordering.
What are the signs of a failing charging coil?
Common symptoms include difficulty starting the engine, weak or no spark, poor engine performance, stalling, and a battery that does not charge properly while the engine is running.
Is this a direct plug-and-play replacement?
Yes, this coil is designed as a direct plug-and-play unit. It uses a factory-style connector that requires no splicing or modification for the compatible models listed.
How does this aftermarket coil differ from the Yamaha OEM part?
While this is an aftermarket part, it is built to meet or exceed original equipment manufacturer (OEM) specifications for fit, form, and function. It uses high-grade copper windings and materials suitable for the marine environment, offering a reliable alternative to the OEM part.
What is the typical lifespan or replacement interval?
Charging coils do not have a fixed replacement interval. They are typically replaced only when they fail. Lifespan can be affected by factors like engine operating temperature, vibration, and exposure to moisture.
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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