Mercury – Quicksilver NGK IZFR6J Laser Iridium Spark Plug | Marine Ignition Component | Sold Individually | 843220Q

Overview

The Quicksilver 843220Q NGK IZFR6J Laser Iridium Spark Plug is built to give your Mercury outboard dependable starts, smooth power, and long service life. It’s the same high-quality plug trusted by Mercury Marine for factory performance, designed to handle the heat and vibration of real-world boating. Each plug comes pre-gapped and ready to install, so you can get back on the water quickly and know your engine is firing right every time.

Key Features

• Purpose: Provides consistent spark for reliable ignition, smooth idle, and efficient fuel burn.
• Material: Built with a laser-welded iridium tip and copper core for better conductivity and heat control.
• Performance: Delivers cleaner combustion, longer life, and easier starts compared to standard plugs.
• Design: Features a ribbed ceramic insulator that helps prevent flashover and reduces misfires under load.
• Ease of Use/Install: Pre-gapped to OEM specs and installs easily with a common spark plug socket.

Compatibility

• Engines: Mercury Marine outboards and compatible marine engines (verify with your owner’s manual)
• Replaces: NGK IZFR6J Spark Plug
• Use On: Outboards | Sterndrives | Jet Boats | Powersports Engines

Performance & Real-World Benefits

Boaters who switch to the IZFR6J Iridium plug often notice faster starts, smoother throttle response, and better fuel efficiency. The iridium tip holds its edge far longer than standard electrodes, meaning more reliable spark over time. NGK’s ceramic insulator helps the plug stay cooler and cleaner, even after long days on the water. It’s the kind of part you install once and don’t have to think about again for a long while.

Why Choose OEM

Choosing Quicksilver and NGK OEM parts means you’re using components designed exactly for your engine—not a close copy. OEM plugs match Mercury’s exact heat range, thread depth, and gap settings to keep performance consistent. Aftermarket versions can fall short on fit or wear faster, which affects power and efficiency. With OEM, you’re getting the same dependable quality your motor was built with, and that’s worth keeping.

FAQ

Q1: Are these plugs pre-gapped and ready to go?
Yes, they come pre-gapped at the correct setting for Mercury outboards. Just double-check your manual to be sure.

Q2: Can I mix these with other plug types?
It’s best not to. Replacing all your plugs at once with the same type ensures smooth, even performance.

Q3: How long will these last compared to standard plugs?
Iridium plugs last much longer—often two to three times the lifespan of traditional copper ones.

Q4: Do they resist corrosion in saltwater?
Yes, the trivalent metal plating keeps them from seizing and helps protect against rust in marine use.

Q5: What’s in the package?
Each box includes one NGK Laser Iridium spark plug, ready for installation.