Sierra 18-8807-1 Spark Plug Wire Set, Replaces OMC 503747, for OMC Sterndrive/Cobra 2.3L 4-Cylinder Engines

The Sierra 18-8807-1 is a premium MagForce spark plug wire set engineered for OMC Sterndrive/Cobra stern drive engines. Built with a Kevlar core for durability and long service life, the wires use a durable stainless steel wound conductor to support maximum horsepower and engine performance. Premium silicone jacketing and boots provide high-temperature protection at the plug and distributor connections, while the construction delivers superior RFI suppression for engines running sensitive electronic systems. Corrosion-resistant stainless steel spark plug and distributor terminals maintain reliable conductivity in the marine environment. This wire set is designed to replace OMC 503747 and is the correct plug wire set for OMC Sterndrive/Cobra 2.3L 4-cylinder engines from 1987 to 1990. The set includes one full set of wires sized for a 4-cylinder engine, ready to install as a direct replacement for worn, cracked, or misfiring original wires.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-8807-1
• Product Type: Spark Plug Wire Set
• Material: Kevlar, Silicone
• Conductor: Stainless steel wound conductor
• Terminals: Corrosion resistant stainless steel spark plug and distributor terminals
• Weight: 1.12 pounds
• Cylinder Count: 4
• OEM Cross Reference: OMC 503747

Fitment

• OMC Sterndrive/Cobra 2.3L, 4-cylinder, 1987-1990

Replaces (OEM)

• OMC 503747

Frequently Asked Questions

What engines does the Sierra 18-8807-1 spark plug wire set fit? The 18-8807-1 is designed for OMC Sterndrive/Cobra 2.3L, 4-cylinder engines built from 1987 to 1990.

Does this wire set replace OMC 503747? Yes, the Sierra 18-8807-1 is a direct replacement for OMC part number 503747.

What is the wire set made of? It is built with a Kevlar core and a durable stainless steel wound conductor, wrapped in premium silicone jacketing and boots for high-temperature protection.

How many spark plug wires are in the 18-8807-1 set? The set is sized for a 4-cylinder engine, providing one wire per cylinder to match the OMC Sterndrive/Cobra 2.3L application.

How much does the 18-8807-1 wire set weigh? This Sierra spark plug wire set weighs 1.12 pounds.

Are the terminals corrosion resistant? Yes, the 18-8807-1 uses corrosion resistant stainless steel spark plug and distributor terminals for reliable conductivity in marine conditions.

Does this wire set help with RFI interference? Yes, the silicone jacketing and construction of the 18-8807-1 provide superior RFI suppression, which benefits engines with sensitive electronic systems.

Is the Sierra 18-8807-1 an OEM or aftermarket part? The 18-8807-1 is a Sierra-branded aftermarket wire set manufactured as a direct replacement for OMC 503747.

Why would I replace my spark plug wires with the 18-8807-1? Cracked, worn, or degraded silicone jacketing on original wires can cause misfires and RFI interference; the 18-8807-1 restores proper spark delivery with new Kevlar-core, stainless steel wound wires.

Can I use the 18-8807-1 on a 6-cylinder or 8-cylinder OMC engine? No, the 18-8807-1 is sized specifically for the 4-cylinder 2.3L OMC Sterndrive/Cobra application; other cylinder counts require a different Sierra plug wire set.