Repairing Threads In Block For Cylinder Head Bolts

NOTE: Use 12 x 1.75 mm Heli-Coil or suitable equivalent thread repair equipment.

1. Remove cylinder head.
2. Widen bore.
3. Tap Heli-Coil thread
4. Screw In Heli-Coil thread.

Specifications
Size "a" Diameter: 14.00 - 14.27 mm
Twist Drill Diameter: 12.5 mm
Core Hole Depth From Contact Surface: 35 mm
Heli-Coil threaded insert below contact surface: 5.3 mm
Heli-Coil thread length screwed in: 26 mm
Heli-Coil thread length block size: 23.1 mm