NGK Spark Plug – BR6ES

The NGK BR6ES is a standard copper-core nickel spark plug used in select marine outboards, motorcycles, ATVs, small engines, and utility equipment where the manufacturer specifies the BR6ES / NGK 4922 plug profile. It features a resistor design to help reduce ignition-related RFI noise and a gasket-seat 14 mm body for engines that require this plug style.

Key Features

• NGK part number: BR6ES
• NGK stock number: 4922
• Copper-core nickel construction
• Built-in resistor for RFI suppression
• Thread diameter: 14 mm
• Thread reach: 19 mm / 3/4 in.
• Hex size: 13/16 in. / 21 mm
• Seat style: flat / gasket seat
• Heat range: 6
• Factory preset gap reference: 0.035 in. / 0.9 mm
• Standard non-projected firing-end design

Application Compatibility

Common application context includes engines where the factory plug chart calls for NGK BR6ES / 4922, including:

• Select Mercury / Mariner outboard applications where specified
• Select powersports and ATV engines where specified
• Select vintage motorcycle applications where specified
• Select small-engine, generator, saw, and utility equipment applications where specified

Use this plug only where the manufacturer’s application chart lists BR6ES, 4922, or an approved equivalent.

Fitment Notice

Confirm fitment by exact engine model, serial number, year, service manual, and factory spark plug chart before ordering. Spark plugs with the same thread size can still differ in reach, heat range, seat style, projection, terminal type, resistor design, and required gap.

When This Part Needs Replacement

Replace spark plugs during scheduled tune-up service or when the plug is worn, fouled, oil-contaminated, fuel-soaked, corroded, cracked, or causing hard starting, rough idle, hesitation, misfire, or poor low-speed running.

Installation Notes

Check the required gap before installation. Install into clean, undamaged threads and tighten to the engine manufacturer’s torque specification. Because this is a gasket-seat plug, confirm the sealing washer is present and seats correctly. Avoid anti-seize unless the manufacturer specifically calls for it.

Alternate/Superseded Part Numbers

• NGK BR6ES
• NGK 4922
• Mercury 33-813471 1 marine reference; verify by engine serial number and plug chart
• BR6EIX iridium-style upgrade reference; verify by application
• BR6EG fine-wire/racing-style reference; verify by application

Parts Desk Insight

The BR6ES should be matched by exact plug number and engine chart, not by thread size alone. Correct reach, gasket-seat design, heat range, and gap are critical for reliable ignition and cylinder-head safety.

Shipping: Ships same or next day for fast Canada wide shipping.