Sierra 18-5228-1 MagForce 9 Inch 8mm Spark Plug Wire, Replaces Mercury 84-813715A1

The Sierra 18-5228-1 is a 9 inch, 8mm MagForce ignition wire built for Mercury and Mariner outboard ignition systems. It is designed as an electronics friendly replacement lead, meaning it shields onboard electronic engine controls and other electronic devices from RFI and EMI interference while still delivering the full voltage the ignition system needs to fire the plug reliably. The exact fit design matches the original wire's dimensions and connector style, so it installs the same way the factory lead did without any modification or splicing.

Each end terminates in a boot-style connector for a secure, weather-resistant seal at the spark plug and coil or distributor connection. This wire directly replaces Mercury part number 84-813715A1, making it a straightforward drop-in swap when an original equipment lead has cracked, arced, or lost continuity. Sierra builds each wire to meet or exceed the specifications of the original equipment part it replaces, so performance and durability match what the engine shipped with.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-5228-1
• Product Name: Wiring Plug Set
• Wire Length: 9 inches
• Wire Gauge: 8mm
• Connector Type: Boot Style
• Material: Nylon
• Item Dimensions: 0.39 x 0.39 x 0.39 inches
• Weight: 0.08 pounds
• Category: Mercury Outboard Spark Plug Wires
• Replaces (OEM): 84-813715A1

Fitment

• Outboard - Mercury/Mariner ignition system

Replaces (OEM)

• 84-813715A1

Frequently Asked Questions

What does the Sierra 18-5228-1 spark plug wire fit? The Sierra 18-5228-1 is built for the Mercury/Mariner outboard ignition system, matching the fit of the original equipment wire it replaces.

What OEM part number does the 18-5228-1 replace? It directly replaces Mercury part number 84-813715A1, so it can be ordered as a drop-in substitute for that original equipment wire.

How long is this spark plug wire? The Sierra 18-5228-1 measures 9 inches in length with an 8mm wire gauge.

What is the wire gauge of the 18-5228-1? It is an 8mm spark plug wire, sized to match the original 9 inch Mercury/Mariner lead it replaces.

What connector style does the 18-5228-1 use? This wire terminates in a boot-style connector at the spark plug end for a secure, weather-resistant fit.

What material is the 18-5228-1 made from? The connector housing on the Sierra 18-5228-1 is nylon, chosen for heat resistance and a snug seal over the plug.

How much does the 18-5228-1 weigh? The Sierra 18-5228-1 spark plug wire weighs 0.08 pounds.

Is the 18-5228-1 safe for electronic engine controls? Yes, Sierra's MagForce construction on the 18-5228-1 is designed to be electronics friendly, protecting electronic engine controls and other onboard electronics from RFI and EMI interference.

Is the Sierra 18-5228-1 an OEM part or aftermarket? The 18-5228-1 is a Sierra aftermarket replacement wire engineered to meet or exceed the quality of the original Mercury 84-813715A1 equipment it replaces.

How many of these wires do I need for my engine? The 18-5228-1 is sold as a single 9 inch, 8mm wire; the number required depends on how many spark plugs your Mercury/Mariner outboard has.

Will the 18-5228-1 install without modification? Yes, it uses an exact fit design matching the original Mercury/Mariner wire, so it installs the same way as the factory 84-813715A1 lead without cutting or splicing.

What is included when I order the 18-5228-1? Each order includes one Sierra 18-5228-1 plug wire with its boot-style connector attached, ready to install in place of the original Mercury 84-813715A1 lead.