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98141 - Pro-Thread 14mm Spark Plug Repair Kit - Tapered Seat

SKU 98141
Original price $53.45 - Original price $53.45
Original price
$53.45 - $53.45
Current price $53.45

Orders placed before 12:00pm EST Mon-Fri ship same day. Orders placed after 12:00pm EST ship next business day.

  • Repairs 14mm tapered seat and gasketed spark plug ports in aluminum and cast iron heads
  • No drilling required
  • Includes: tap, expanding tool & one each of 3 sizes of inserts.
    • 98142 - 1/4” Insert
    • 98143 - 3/8” Insert
    • 98144 - 5/8” Insert
  • Pro-Thread Kit MTC 14 - 1.25
  • Hex head with internal 3/8" drive

TAP: Pilot nose taps require no pre-drilling. Lubricate the tap with o suitable lubricant. Hand start tap and then turn with 19mm or ¾” socket wrench. Tap entire length of port.

SELECT INSERT: Ensure selected insert is the same length as the thread on the spark plug. The knurled end of the insert should be at the top of the spark plug port.

INSTALL INSERT: Wind the correct insert on to the spark plug. Coat outside threads with hi-temp silicone. Wind assembly into spark plug port until fully seated. Wind spark plug out.

COMPLETE INSTALLATION: Place swage tool into insert and hit several times to expand knurl. Install spark plug to recommended torque. Do not run engine until sealant has cured (refer to manufacturers instructions).

*Individual Inserts are also available separately