Mercury – Quicksilver 816336Q NGK BPR6EFS Standard Spark Plug | Sold Individually | Marine Engine OEM Plug | 816336Q

Overview

A fresh set of plugs can make your engine feel brand new. The Quicksilver 816336Q NGK BPR6EFS Standard Spark Plug delivers consistent ignition, better combustion, and long-lasting performance for your Mercury Marine engine. Pre-gapped to factory specifications, it’s ready to drop in and get your motor firing crisp and clean.

Whether you’re running a quiet cruise or throttling hard, reliable spark makes all the difference. Built with NGK’s trusted marine design and backed by Mercury’s engineering, this plug gives you steady starts, smoother idling, and strong top-end performance every time you head out.

Key Features

• Purpose: Provides consistent, reliable spark for optimum engine performance and fuel efficiency.
• Fitment: For Mercury and Mariner outboards and inboards that specify NGK BPR6EFS spark plugs — always confirm in your owner’s manual.
• Pre-Gapped: Comes set to factory gap specs, but it’s recommended to double-check before installation.
• Construction: Features a copper core for superior heat transfer and efficient combustion.
• Durability: Trivalent metal plating prevents corrosion and seizing, making removal easier after long use.
• Insulator Design: NGK’s alumina silicate ceramic insulator offers strength and excellent heat control.

Engine & Boat Compatibility

• Used across multiple Mercury and Mariner outboards and MerCruiser inboards that require NGK BPR6EFS plugs
• Common on fishing boats, cruisers, and performance rigs where reliability is key

Performance & Practical Benefits

A new spark plug can transform how your engine feels. The 816336Q ensures each cylinder fires cleanly, reducing misfires and improving fuel economy. The copper core design helps move heat away from the firing tip, extending plug life and maintaining proper temperature across a wide RPM range.

The plug’s ribbed ceramic insulator prevents flash-over and misfire, while the triple-sealed construction keeps moisture and combustion gases out. You’ll get easier starts, steady throttle response, and stronger acceleration — even after long hours on the water.

Why Buy OEM

Using the correct spark plug isn’t optional; it’s critical. Mercury’s OEM-approved NGK plugs are matched exactly to your engine’s compression and ignition system. Aftermarket or “equivalent” plugs may have different heat ranges or materials that can cause pre-ignition or poor performance.

With a genuine Quicksilver NGK plug, you’re installing the same part your engine was designed to run on — tested in marine conditions and trusted by professionals worldwide. It’s an inexpensive tune-up item that protects your motor and helps it perform at its best.

FAQ

Q1: What engines use the Quicksilver 816336Q NGK BPR6EFS plug?
A: It fits Mercury and Mariner outboards and some MerCruiser inboards that call for NGK BPR6EFS. Always confirm in your owner’s manual.

Q2: Are these pre-gapped?
A: Yes, they come pre-gapped to Mercury specs, but it’s best to verify before installation.

Q3: What makes these different from automotive plugs?
A: Marine plugs are built to resist corrosion and operate under heavier loads and cooler engine temps typical of marine use.

Q4: Should I replace all plugs at once?
A: Yes. Replacing all plugs together ensures balanced performance across every cylinder.

Q5: How often should I change spark plugs?
A: Inspect yearly and replace every 100 hours or sooner if you notice rough running or poor starting.