NGK Spark Plug 4838 (BP8HN-10) V-Power Replacement for Mercury Outboards 1980-2002 and Mariner Outboards 1985-2002
NGK Spark Plug 4838 (BP8HN-10) V-Power Replacement for Mercury Outboards 1980-2002 and Mariner Outboards 1985-2002
NGK spark plug 4838 (NGK part number BP8HN-10) is a V-Power spark plug built as a replacement for Mercury and Mariner outboard engines. The V-Power design uses a "V" cut in the center electrode to help direct the ignition spark to the edge of the electrode, aiding spark development and improving ignitability compared to a standard flat electrode. The plug uses a copper center electrode core for efficient heat dissipation and conductivity, with a nickel center electrode tip and a nickel ground electrode for durability under marine operating conditions. The threaded terminal design allows for straightforward installation and removal during routine maintenance. Electrical resistance is rated at 1 Ohm with a standard ground configuration. Thread size is 14mm x 1.25mm, matching the mounting thread of the outboard powerheads it is designed for. NGK 4838 (BP8HN-10) is intended for Mercury Outboards built 1980-2002 and Mariner Outboards built 1985-2002; always check your engine and maintenance manual to confirm the correct spark plug for your specific powerhead, and only use plugs recommended by your engine's original equipment manufacturer, since using the wrong plug can reduce performance, reduce fuel economy, or damage the engine. This plug is packaged in a standard pack of 10.
Specifications
- Brand: NGK
- Manufacturer Part Number: 4838
- NGK Part Number: BP8HN-10
- Spark Plug Type: V-Power
- Thread Size: 14mm x 1.25mm
- Resistance: 1 Ohm
- Ground Configuration: Standard
- Center Electrode Core Material: Copper
- Center Electrode Tip Material: Nickel
- Ground Electrode Core Material: Nickel
- Package Quantity: 10 count
- Weight: 0.15 pounds
- UPC: 087295176450
Fitment
- Mercury Outboards, 1980-2002
- Mariner Outboards, 1985-2002
Replaces (OEM)
- Quicksilver / Mercury 33-816737Q
- Yamaha BP8-HS-100-00-00
- Johnson / Evinrude 0509569
Frequently Asked Questions
What engines does NGK spark plug 4838 (BP8HN-10) fit? NGK 4838 (BP8HN-10) is designed for Mercury Outboards built 1980-2002 and Mariner Outboards built 1985-2002. Always confirm against your engine's maintenance manual before ordering.
What OEM part numbers does the NGK BP8HN-10 replace? The NGK BP8HN-10 (stock number 4838) replaces Quicksilver/Mercury 33-816737Q, Yamaha BP8-HS-100-00-00, and Johnson/Evinrude 0509569.
Is NGK 4838 a genuine NGK plug or an aftermarket copy? NGK 4838 is a genuine NGK V-Power spark plug carrying the NGK part number BP8HN-10, not a third-party aftermarket copy of an OEM design.
What is the thread size on the NGK BP8HN-10 spark plug? The NGK BP8HN-10 (part 4838) has a 14mm x 1.25mm thread, matching the mounting thread on the Mercury and Mariner outboard powerheads it is built for.
What electrode materials does NGK 4838 use? NGK 4838 uses a copper center electrode core with a nickel center electrode tip and a nickel ground electrode, a combination chosen for heat dissipation and conductivity.
How many spark plugs come in a pack of NGK 4838? NGK spark plug 4838 (BP8HN-10) is packaged in a standard pack of 10.
What does the "V" cut in the NGK BP8HN-10 electrode do? The V-Power design in the NGK BP8HN-10 (4838) cuts a "V" into the center electrode to help direct the ignition spark to the electrode edge, aiding spark development and ignitability.
Is NGK BP8HN-10 the same as NGK BP7HS-10? No. NGK 4838 (BP8HN-10) is a V-Power plug fit for Mercury Outboards 1980-2002 and Mariner Outboards 1985-2002, while BP7HS-10 is a separate NGK Standard plug listed for different Mercury, Nissan, and Tohatsu outboard applications; they are not interchangeable part numbers.
What is the electrical resistance rating of NGK 4838? NGK spark plug 4838 (BP8HN-10) has a resistance rating of 1 Ohm with a standard ground configuration.
How do I install the NGK BP8HN-10 spark plug? The NGK BP8HN-10 (4838) uses a threaded terminal for straightforward installation and removal; check your engine's maintenance manual for correct torque and gap before installing.
Can using the wrong spark plug damage my outboard? Yes. Using a plug other than the one recommended by your engine manufacturer, in place of NGK 4838 where it is specified, can reduce performance, lower fuel economy, or cause engine damage.
How much does the NGK 4838 spark plug weigh? NGK spark plug 4838 (BP8HN-10) weighs 0.15 pounds.