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Engine & Drive Parts

Engine & Drive Parts

  • Sold Out, please call for ETA.
    NGK Spark Plugs 3961 Spark Plug Solid 3961

    NGK Spark Plugs 3961 Spark Plug Solid 3961

    NGK Spark Plugs

    $4.09 $0.00
    NGK Spark Plugs 3961 Spark Plug Solid 3961Chosen by more automotive, and marine engine manufacturers than any other. The unique copper core and exclusive electrode design assure fast starts, peak performance and long life.•?Triple gasket sealing process...
    Part Number:
    41-BR8ESST
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    3961
    Pack:
    10
    Pkg.:
    Boxed
  • NGK Spark Plugs 3981 Spark Plug 3981

    NGK Spark Plugs 3981 Spark Plug 3981

    NGK Spark Plugs

    $17.29 $9.36
    NGK Spark Plugs 3981 Spark Plug 3981Designed specifically for the performance enthusiast. Iridium IX offers extreme ignitability, improved throttle response and superior anti-fouling.Fine-tipped iridium-center electrode ensures high durability and...
    Part Number:
    41-BR9EIX
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    3981
    Pack:
    4
    $17.29 $9.36
  • NGK Spark Plugs 4043 Spark Plug 4043

    NGK Spark Plugs 4043 Spark Plug 4043

    NGK Spark Plugs

    $6.19 $4.28
    NGK Spark Plugs 4043 Spark Plug 4043V-Power plugs offer economical performance and improved ignitability over nickel spark plugs. OEM and racer approved.Lowers ignition system voltage requirementsIncreased fuel economyHigh durability resists electrical...
    Part Number:
    41-ZFR4F11
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4043
    Pack:
    4
    Pkg.:
    Boxed
    $6.19 $4.28
  • Sold Out, please call for ETA.
    NGK Spark Plugs 4076 Spark Plug 4076

    NGK Spark Plugs 4076 Spark Plug 4076

    NGK Spark Plugs

    $13.49 $9.25
    NGK Spark Plugs 4076 Spark Plug 4076Racing plugs feature a center electrode with a V-groove and a thicker ceramic shell for the high-heat applications in racing engines.Special center electrode designs and configurations to ensure durability and...
    Part Number:
    41-R6254K105
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4076
    Pack:
    4
  • Sold Out, please call for ETA.
    NGK Spark Plugs 4177 Spark Plug 4177

    NGK Spark Plugs 4177 Spark Plug 4177

    NGK Spark Plugs

    $5.29 $3.84
    NGK Spark Plugs 4177 Spark Plug 4177V-Power plugs offer economical performance and improved ignitability over nickel spark plugs. OEM and racer approved.Lowers ignition system voltage requirementsIncreased fuel economyHigh durability resists electrical...
    Part Number:
    41-TR6
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4177
    Pack:
    4
    Pkg.:
    Boxed
  • Sold Out, please call for ETA.
    NGK Spark Plugs 4210 Spark Plug 4210

    NGK Spark Plugs 4210 Spark Plug 4210

    NGK Spark Plugs

    $4.09 $0.00
    NGK Spark Plugs 4210 Spark Plug 4210Chosen by more automotive, and marine engine manufacturers than any other. The unique copper core and exclusive electrode design assure fast starts, peak performance and long life.•?Triple gasket sealing process...
    Part Number:
    41-B5HS
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4210
    Pack:
    4
    Pkg.:
    Boxed
  • NGK Spark Plugs 4291 Spark Plug 4291

    NGK Spark Plugs 4291 Spark Plug 4291

    NGK Spark Plugs

    $6.19 $4.28
    NGK Spark Plugs 4291 Spark Plug 4291V-Power plugs offer economical performance and improved ignitability over nickel spark plugs. OEM and racer approved.Lowers ignition system voltage requirementsIncreased fuel economyHigh durability resists electrical...
    Part Number:
    41-ZFR6F11
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4291
    Pack:
    4
    Pkg.:
    Boxed
    $6.19 $4.28
  • Sold Out, please call for ETA.
    NGK Spark Plugs 4322 Spark Plug Br8Hs

    NGK Spark Plugs 4322 Spark Plug Br8Hs

    NGK Spark Plugs

    $4.09 $0.00
    NGK Spark Plugs 4322 Spark Plug Br8HsChosen by more automotive, and marine engine manufacturers than any other. The unique copper core and exclusive electrode design assure fast starts, peak performance and long life.•?Triple gasket sealing process...
    Part Number:
    41-BR8HS
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4322
    Pack:
    10
    Pkg.:
    Boxed
  • NGK Spark Plugs 4522 Spark Plug 4522

    NGK Spark Plugs 4522 Spark Plug 4522

    NGK Spark Plugs

    $5.89 $4.13
    NGK Spark Plugs 4522 Spark Plug 4522Chosen by more automotive, and marine engine manufacturers than any other. The unique copper core and exclusive electrode design assure fast starts, peak performance and long life.•?Triple gasket sealing process...
    Part Number:
    41-BR9HS
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4522
    Pack:
    10
    Pkg.:
    Boxed
    $5.89 $4.13
  • NGK Spark Plugs 4548 Spark Plug 4548

    NGK Spark Plugs 4548 Spark Plug 4548

    NGK Spark Plugs

    $19.79 $10.26
    NGK Spark Plugs 4548 Spark Plug 4548Chosen by more automotive, and marine engine manufacturers than any other. The unique copper core and exclusive electrode design assure fast starts, peak performance and long life.•?Triple gasket sealing process...
    Part Number:
    41-CR9EK
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4548
    Pack:
    10
    Pkg.:
    Boxed
    $19.79 $10.26
  • Sold Out, please call for ETA.
    NGK Spark Plugs 4549 Spark Plug 4549

    NGK Spark Plugs 4549 Spark Plug 4549

    NGK Spark Plugs

    $4.29 $0.00
    NGK Spark Plugs 4549 Spark Plug 4549Chosen by more automotive, and marine engine manufacturers than any other. The unique copper core and exclusive electrode design assure fast starts, peak performance and long life.•?Triple gasket sealing process...
    Part Number:
    41-CR7HSA
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4549
    Pack:
    10
    Pkg.:
    Boxed
  • NGK Spark Plugs 4551 Spark Plug 4551

    NGK Spark Plugs 4551 Spark Plug 4551

    NGK Spark Plugs

    $5.89 $4.13
    NGK Spark Plugs 4551 Spark Plug 4551Chosen by more automotive, and marine engine manufacturers than any other. The unique copper core and exclusive electrode design assure fast starts, peak performance and long life.•?Triple gasket sealing process...
    Part Number:
    41-BR9HS10
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4551
    Pack:
    10
    Pkg.:
    Boxed
    $5.89 $4.13
  • NGK Spark Plugs 4554 Spark Plug 4554

    NGK Spark Plugs 4554 Spark Plug 4554

    NGK Spark Plugs

    $12.09 $6.73
    NGK Spark Plugs 4554 Spark Plug 4554Racing plugs feature a center electrode with a V-groove and a thicker ceramic shell for the high-heat applications in racing engines.Special center electrode designs and configurations to ensure durability and...
    Part Number:
    41-R5671A8
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4554
    Pack:
    4
    $12.09 $6.73
  • Sold Out, please call for ETA.
    NGK Spark Plugs 4578 Spark Plug 4578

    NGK Spark Plugs 4578 Spark Plug 4578

    NGK Spark Plugs

    $8.89 $0.00
    NGK Spark Plugs 4578 Spark Plug 4578Chosen by more automotive, and marine engine manufacturers than any other. The unique copper core and exclusive electrode design assure fast starts, peak performance and long life.•?Triple gasket sealing process...
    Part Number:
    41-CR7E
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4578
    Pack:
    10
    Pkg.:
    Boxed
  • NGK Spark Plugs 4623 Spark Plug 4623

    NGK Spark Plugs 4623 Spark Plug 4623

    NGK Spark Plugs

    $5.89 $4.13
    NGK Spark Plugs 4623 Spark Plug 4623Chosen by more automotive, and marine engine manufacturers than any other. The unique copper core and exclusive electrode design assure fast starts, peak performance and long life.•?Triple gasket sealing process...
    Part Number:
    41-DR5HS
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4623
    Pack:
    10
    Pkg.:
    Boxed
    $5.89 $4.13
  • Sold Out, please call for ETA.
    NGK Spark Plugs 4629 Spark Plug 4629

    NGK Spark Plugs 4629 Spark Plug 4629

    NGK Spark Plugs

    $4.29 $0.00
    NGK Spark Plugs 4629 Spark Plug 4629Chosen by more automotive, and marine engine manufacturers than any other. The unique copper core and exclusive electrode design assure fast starts, peak performance and long life.•?Triple gasket sealing process...
    Part Number:
    41-C7HSA
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4629
    Pack:
    10
    Pkg.:
    Boxed
  • NGK Spark Plugs 4644 Spark Plug Vpower 4644

    NGK Spark Plugs 4644 Spark Plug Vpower 4644

    NGK Spark Plugs

    $6.19 $4.21
    NGK Spark Plugs 4644 Spark Plug Vpower 4644V-Power plugs offer economical performance and improved ignitability over nickel spark plugs. OEM and racer approved.Lowers ignition system voltage requirementsIncreased fuel economyHigh durability resists...
    Part Number:
    41-BKR7E
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4644
    Pack:
    4
    Pkg.:
    Boxed
    $6.19 $4.21
  • NGK Spark Plugs 4677 Spark Plug 4677

    NGK Spark Plugs 4677 Spark Plug 4677

    NGK Spark Plugs

    $16.59 $8.41
    NGK Spark Plugs 4677 Spark Plug 4677Chosen by more automotive, and marine engine manufacturers than any other. The unique copper core and exclusive electrode design assure fast starts, peak performance and long life.•?Triple gasket sealing process...
    Part Number:
    41-BR9ECS
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4677
    Pack:
    10
    Pkg.:
    Boxed
    $16.59 $8.41
  • Sold Out, please call for ETA.
    NGK Spark Plugs 4684 Spark Plug 4684

    NGK Spark Plugs 4684 Spark Plug 4684

    NGK Spark Plugs

    $0.00
    NGK Spark Plugs 4684 Spark Plug 4684Chosen by more automotive, and marine engine manufacturers than any other. The unique copper core and exclusive electrode design assure fast starts, peak performance and long life.•?Triple gasket sealing process...
    Part Number:
    41-BR10ESSLD
    Availability:
    In Stock - Ships same or next business day.
    Model #:
    4684
    Pack:
    10
    Pkg.:
    Boxed

Spark Plugs for Power Boats

Keep your engine performing at its best with high-quality boat spark plugs designed for outboards, inboards, and sterndrives. At PowerBoatSupply.com, we carry a full selection of NGK spark plugs, AC Delco spark plugs, and other trusted marine brands to fit a wide variety of engines. Whether you’re replacing a single spark plug for a boat motor or outfitting an entire set, you’ll find durable, OEM-recommended options that deliver reliable ignition, smooth starts, and long-lasting performance on the water.

Why Spark Plugs Matter for Marine Engines

Spark plugs are a small but critical part of your boat’s ignition system. They provide the spark that ignites the fuel-air mixture, powering your engine forward. Worn or fouled boat motor spark plugs can lead to misfires, poor fuel economy, hard starts, or even engine damage. That’s why routine replacement with the right spark plug type is essential for keeping your boat running smoothly all season long.

Our Spark Plug Selection

We stock a wide range of marine spark plugs to cover all your needs, including:

  • Standard spark plugs – affordable and dependable for routine use
  • V-Power spark plugs – improved ignitability for better performance
  • Iridium spark plugs – advanced durability and longer service life
  • OEM-specific plugs – designed to fit Mercury, MerCruiser, and other popular marine engines

From Mercury outboards to MerCruiser sterndrives, our inventory includes the correct Mercury boat motor spark plugs to keep your engine running at peak efficiency.

When to Replace Your Spark Plugs

Most marine experts recommend inspecting and replacing spark plugs every season, or at least every 100 hours of operation. Signs that your plugs need replacement include difficulty starting, engine hesitation, reduced fuel efficiency, or visible carbon buildup on the electrodes. Swapping them out regularly is an inexpensive way to protect your boat engine and prevent costly repairs.

Shop Spark Plugs Online With Confidence

PowerBoatSupply.com makes it easy to find the exact boat spark plugs you need. With fast shipping, competitive pricing, and our decades of marine parts experience, we’re your trusted source for boat motor spark plugs and engine tune-up parts. Order today and get back on the water with confidence.