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3/8DR TORQUE RATCHET F/SPARK PLUG - Koken

Part #: 3751J-25

Ensure precise and damage-free spark plug installation with the Koken 3751J-25 3/8" Drive Torque Ratchet. Engineered for professional technicians, this specialized tool delivers a fixed 25Nm of torque, meticulously calibrated to prevent over-tightening, safeguarding delicate spark plug threads and cylinder heads. This professional-grade ratchet is an essential addition for reliable automotive maintenance.

Key Features

  • Fixed Torque Setting: Pre-set at 25Nm (Newton-meters) to provide the exact torque required for most spark plug installations, eliminating guesswork and preventing costly damage.
  • Over-Torque Protection: Features a unique slipping mechanism where the gear disengages once 25Nm is reached, ensuring no additional torque is transmitted and protecting cylinder heads and spark plugs from excessive force.
  • Durable Construction: Manufactured in Japan, this Koken ratchet is built from high-quality materials, including a polished finish and robust Acrylonitrile Butadiene Styrene components, ensuring longevity and consistent performance in demanding workshop environments.
  • Optimized for Spark Plugs: Specifically designed for spark plug applications, offering the control and precision needed for critical engine components.

Applications

The Koken 3751J-25 Torque Ratchet is ideal for professional mechanics and technicians performing routine maintenance or engine repair. Its precise torque control makes it indispensable for installing spark plugs in various vehicle types, ensuring proper seating and preventing common issues like stripped threads or cracked insulators.

Specifications

  • Manufacturer: Koken
  • Model Number: 3751J-25
  • Drive Size: 3/8 inch square drive
  • Torque: 25Nm (fixed)
  • Length: 178mm (7 inches)
  • Weight: 0.32 kg (0.71 lb)
  • Country of Origin: Japan
Only 6 left in stock - order soon
List: $139.99 Save: $32.86

$107.13

Free shipping on orders over $250
Lower 48 states and DC. Excludes freight and oversize items.
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  • Model: 423945
  • Shipping Weight: 0.68lbs
  • Manufacturers Part #: 3751J-25
  • Manufactured by: Koken
  • Also Known As: KKN3751J-25

This product was added to our catalog on Tuesday 12 May, 2026.

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