7" Spark Plug Wire – Fits Mercury Marine 150-200 HP (Replaces 84-813715A1)
7" Spark Plug Wire – Fits Mercury Marine 150-200 HP (Replaces 84-813715A1) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
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7" Spark Plug Wire – Fits Mercury Marine 150-200 HP (Replaces ...
7" Spark Plug Wire – Fits Mercury Marine 150-200 HP (Replaces 84-813715A1) is backordered and will ship as soon as it is back in stock.
Product Details
This 7-inch spark plug ignition wire is engineered for Mercury Marine 150-200 HP V6 outboard motors manufactured between 1970–1988, including the V-150, V-175, and V-200 series. It establishes a secure, reliable electrical connection from the ignition coil or distributor to the spark plug, ensuring proper engine firing.
This component is a direct interchange for Mercury part numbers 84-813715A1, 90816A25, 93475A25, 99215A25, and 99215A29, as well as Sierra 18-8819.
- Designed for direct, hassle-free replacement.
- Constructed with silicone insulation and stainless steel components for durability.
- Features a terminal end for the coil/distributor and a boot for the spark plug.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 84-813715A1 |
| Mercury | 90816A25 |
| Mercury | 93475A25 |
| Mercury | 99215A25 |
| Mercury | 99215A29 |
| Sierra | 18-8819 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
Fitment is verified for the following Mercury Marine outboard engines.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | V-150 | 150 | 2-Stroke | 1970–1988 | 84-813715A1 | Serial range: 4868998-0A904645 |
| Mercury | V-150 Magnum | 150 | 2-Stroke | 1970–1988 | 84-813715A1 | Serial range: 5600162-0A904645 |
| Mercury | V-150 Marathon | 150 | 2-Stroke | 1970–1988 | 84-813715A1 | Serial range: 5600162-0A904645 |
| Mercury | V-150 Work | 150 | 2-Stroke | 1970–1988 | 84-813715A1 | Serial range: 4868998-0A904645 |
| Mercury | V-150-XR-2 | 150 | 2-Stroke | 1970–1988 | 84-813715A1 | Serial range: 4868998-0A904645 |
| Mercury | V-1500 | 150 | 2-Stroke | 1970–1988 | 84-813715A1 | Serial range: 4868998-0A904645 |
| Mercury | V-175 | 175 | 2-Stroke | 1970–1988 | 84-813715A1 | Serial range: 4301235-0C100860, 8058870-UP |
| Mercury | V-200 | 200 | 2-Stroke | 1970–1988 | 84-813715A1 | Serial range: 5239232-0C100860 |
Technical Specs
- Product Type
- Spark Plug Wire
- Installation
- Direct replacement
- Length
- 7 inches (178 mm)
- Compatible With
- Mercury Marine outboard engines
- Material
- Silicone insulation with stainless steel components
- Connection Type
- Terminal end connects to coil/distributor, boot end connects to spark plug
- Color
- Black
- Warranty
- 1 Year (retailer dependent)
What’s in the Box
- 1 x 7" Spark Plug Wire (Replaces 84-813715A1/90816A25/93475A25/99215A25/99215A29)
Installation Notes
- Ensure the engine is off and completely cool. For safety, disconnect the battery.
- Note the routing of the existing wire from the distributor/coil to the spark plug.
- Gently twist and pull the spark plug boot to remove it from the plug. Do not pull on the wire itself.
- Disconnect the wire's terminal end from the ignition coil or distributor cap.
- Lightly apply dielectric grease to the inside of the new wire's boots for a better seal and easier future removal.
- Securely connect the terminal end of the new wire to the corresponding post on the coil or distributor.
- Route the new wire along the original path, ensuring it is clear of hot or moving parts.
- Press the spark plug boot firmly onto the spark plug until you feel it click into place.
- Reconnect the battery, start the engine, and check for smooth operation.
Troubleshooting & FAQ
How do I know if this wire will fit my specific engine model?
This wire is designed for specific Mercury Marine V6 outboards from 1970–1988. The most reliable way to confirm fitment is by checking your engine's serial number against the ranges listed in the "Engine & Model Compatibility" table above. Cross-referencing your old part number with the "Part Number Matrix" is also an excellent verification step.
What are common signs of a failing spark plug wire?
Symptoms of a bad ignition wire include engine misfires (especially under load), rough idling, reduced power, poor acceleration, and decreased fuel economy. You might also notice visible damage to the wire, such as cracks, burns, or corrosion on the terminals.
How often should I replace my spark plug wires?
There is no universal replacement interval, as it depends on engine hours, operating conditions, and exposure to heat or chemicals. It's best practice to inspect them during regular maintenance (e.g., when changing spark plugs) and replace them if you notice any signs of wear, damage, or performance issues.
Can I test my old spark plug wire to see if it's bad?
Yes, you can test an ignition wire's resistance using a multimeter. Set the multimeter to ohms and measure from end to end. The acceptable resistance varies by wire length and type, but a reading of infinity (open circuit) or very high, fluctuating resistance indicates a faulty wire.
What is the difference between OEM and this aftermarket part?
This listing is an aftermarket replacement (not OEM). It's built to OEM-level specifications with comparable materials for fit and function. Our parts are manufactured in an ISO 9002 certified facility and are batch-inspected for quality and consistency, offering a reliable alternative at a better value.
What are your shipping speeds and costs?
We ship worldwide quickly—typical transit time is 5–15 days. Standard shipping is free for most orders, with expedited options available at checkout depending on your location.
What is the warranty and return policy on this part?
This part is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter an issue, please contact our support team with your order details. Returns are accepted within our standard window, provided the part is unused and in its original condition. Please see our full policy page or reach out for instructions.
Safety & Important Info
- Verify images and specifications against 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 thoroughly tested for real-world conditions.
- Fast Global Fulfillment — We offer free standard delivery to most regions with a typical transit time of 5–15 days.
- Manufacturer-Direct Value — Our direct-sourcing model allows us to provide fair pricing without compromising on materials or quality control.
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