Sierra 18-5231-1 Spark Plug Wire 9" Single

A single 9 in replacement spark plug wire for Johnson and Evinrude outboards. Plug wires are a maintenance item people ignore until a cylinder starts dropping under load, and on an outboard the failure is usually the boot or the terminal rather than the conductor, because both live in salt air and heat.

• Length: 9 in (228.6 mm), sold individually so you replace what you need.
• Terminals: corrosion-resistant stainless steel spark plug and distributor terminals for conductivity that holds up.
• Conductor: stainless steel wound, with RFI suppression for sensitive electronics. That matters when a fish finder or a chartplotter is picking up ignition noise.
• Jacket and boots: premium silicone for high temperature service.
• Interchanges with OMC 0582365, Johnson/Evinrude 582365, Mallory 9-28005 and Redline RL5231.

Pull the boot, not the wire. Yanking a plug wire by the cable separates the conductor from the terminal inside the boot and you end up with an intermittent miss that is very hard to chase.