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Tapping Thread In SPARKPLUG Hole

Fig 1: Identifying Tap, Reamer, And Steering (A, B And C)

Courtesy of VOLVO CARS CORPORATION

Use combination tap 998 5823-5 and thread repair inserts for spark plug thread M14x1.25 .

NOTE: Do not drill out spark plug threads.

Combined tap

A: Tap.

B: Reamer.

C: Steering.