Universal Spark Plug Wire Kit – Fits Mercury/Mariner Outboards (Replaces 84-813706A26)
Universal Spark Plug Wire Kit – Fits Mercury/Mariner Outboards (Replaces 84-813706A26) 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
Universal Spark Plug Wire Kit – Fits Mercury/Mariner Outboards (Rep...
Product Details
This Universal Spark Plug Wire Kit provides a high-quality replacement for Mercury/Mariner and other compatible outboard engines. The kit features 25 feet of durable 7mm Hypalon-coated wire with a metallic core, designed to be cut to the required lengths for a custom fit.
It serves as a direct interchange for Sierra 18-5225, Mallory 9-28120, and Mercury part numbers including 84-813706A26, 84-90816A26, 84-93212A1, 84-93475A26, and 84-99215A26.
- Requires cutting wires to length and crimping the included end fittings.
- Resistant to high temperatures, moisture, and abrasion for marine environments.
- Includes three different types of end fittings to accommodate various motor configurations.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Sierra | 18-5225 |
| Mallory | 9-28120 |
| Mercury | 84-813706A26 |
| Mercury | 84-90816A26 |
| Mercury | 84-93212A1 |
| Mercury | 84-93475A26 |
| Mercury | 84-99215A26 |
Engine & Model Compatibility
This is a universal kit designed for a wide range of outboard engines, primarily Mercury and Mariner models. Compatibility is determined by matching the required end fittings with your motor's existing connections. Please verify your requirements before installation.
Technical Specs
- Product Type
- Spark Plug Wire Kit
- Material
- Hypalon with Metallic Core
- Wire Size
- 7 mm
- Length
- 25 feet (7.6 m)
- Connection
- Three Different End Fittings Included
- Installation
- DIY (requires crimping ends to wire)
- Applications
- Outboard Motors
- Housing Color
- Black
- Product Height
- 13.0 in
- Product Width
- 9.0 in
- Product Length
- 2.38 in
What’s in the Box
- 1 x 25 ft (7.6 m) roll of 7mm Hypalon-coated spark plug wire
- 3 x Different sets of end fittings (for custom outboard motor applications)
Installation Notes
- Disconnect the battery before beginning work.
- Replace one spark plug wire at a time to avoid mixing up firing order.
- Remove the old wire and measure it against the new wire roll.
- Cut the new 7mm wire to the same length as the original.
- Select the correct end fittings for both the spark plug and distributor/coil ends.
- Firmly crimp the new fittings onto each end of the cut wire using a proper crimping tool.
- Apply a small amount of dielectric grease to the inside of each boot to seal against moisture and ease installation.
- Securely connect the new wire, ensuring a tight click at both connection points.
- Repeat the process for all remaining wires.
- Once complete, reconnect the battery and test the engine.
Troubleshooting & FAQ
How do I know if this universal kit will fit my engine?
Fitment for this universal kit depends on your ability to use the three included end fittings with your outboard motor's configuration. Compare the ends on your existing wires to the product images and part numbers to determine compatibility. It is designed primarily for Mercury/Mariner outboards but may fit others.
Do I need special tools for installation?
Yes, you will need a wire cutting tool and a specialized crimping tool to securely attach the new end fittings to the wires you cut to length. Dielectric grease is also highly recommended for a proper, moisture-proof seal.
What's the difference between this Hypalon wire and factory wires?
Hypalon is a high-performance synthetic rubber known for its excellent resistance to heat, oil, ozone, and abrasion. While many OEM wires are high quality, this kit's Hypalon coating provides robust durability specifically for the demanding marine environment, often meeting or exceeding factory specifications.
When should I replace my spark plug wires?
Inspect spark plug wires annually or as recommended by your engine manufacturer. Replace them if you find any signs of cracking, burning, or brittleness in the insulation. A general replacement interval is every 5-7 years, but this can vary based on usage and conditions.
What are the signs of failing spark plug wires?
Common symptoms include rough idling, engine misfires (especially under load), increased fuel consumption, difficulty starting the engine, and audible arcing or clicking sounds from the engine bay. A visual inspection may also reveal physical damage to the wires.
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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