Quicksilver 816761Q17 Spark Plug Wire Kit for MerCruiser V8 LH | Thunderbolt IV (1993–2003)

Reliable ignition for MerCruiser V8 engines

The Quicksilver 816761Q17 Spark Plug Wire Kit is crafted as a marine-grade replacement for MerCruiser V8 LH powerplants using Thunderbolt IV ignition systems from 1993 through 2003. This kit offers a complete, factory-style wiring solution designed to support steady starts and smooth idle in demanding sea conditions.

What you get

• Complete set of spark plug wires with boots at the spark plug end
• Tailored to reach the correct plug location without stressing the harness
• Designed for efficiency, endurance and durability in a marine engine environment

Key compatibility and design details

The kit targets MerCruiser V8 LH configurations (305 and 350 CID) with Thunderbolt IV ignition, spanning model years 1993–2003. It aligns with original equipment expectations, offering a practical replacement option when wiring and boots reach the end of their service life.

Why choose Quicksilver

• 65 years of marine industry experience and testing in harsh environments
• Leader in Mercury Marine Original Equipment replacement parts and accessories
• Quality you can feel in fit, finish, and durable construction designed to withstand waves, vibration, and salt spray

Real-world use and expectations

Whether you're cruising at sunset or navigating a choppy afternoon, this kit aims to support reliable ignition and steady running. It offers a practical option when regular maintenance calls for renewed wiring and boots. Benefits are described as possibilities, not guarantees, and will vary with upkeep and operating conditions.

Consider this kit as part of a routine maintenance plan for engines from the Thunderbolt IV era, especially if you value a factory-style wiring solution that aligns with original equipment expectations and marine-duty durability.