Bolt Re-Usability

Cylinder Head Bolt (12-pt Socket with "Closed-Deck")
Thread Diameter "D" 12 mm
Stretch Shank Diameter "d":
When New 10.75 ± 0.05 mm
Thread Length "a" 135 mm
Bolt Length "L":
When New 160 ± 0.8 mm
Maximum Bolt Length 162.70 mm

Cylinder Head Bolt (12-pt Socket with "Open-Deck")
Thread Diameter "D" 12 mm
Stretch Shank Diameter "d":
When New 10.75 ± 0.05 mm
Thread Length "a":
Short Bolt 135 mm
Long Bolt 190 mm
Bolt Length "L":
When New:
Short Bolt 160 ± 0.8 mm
Long Bolt 218 ± 0.9 mm
Maximum Bolt Length:
Short Bolt 162.70 mm
Long Bolt 221.60 mm

Bolt Diagram:

"Closed-Deck" Cylinder Head Bolts Numbers 1 to 10 = M12 x 160 mm
"Open-Deck" Cylinder Head Bolts:
Numbers: 1, 3 and 5 = M12 x 218 mm
Numbers: 2, 4, 6, 7, 8, 9, 10 = M12 x 160 mm

NOTE: Cylinder head bolts: Cylinder head bolts match with washers. "Closed-Deck" cylinder head bolts are phosphatized, washers chrome-plated. "Open-Deck" cylinder head bolts are chrome plated, washers are phosphatized.
No "HELI-COIL inserts are installed in crankcase of "open-deck version. HELI-COIL inserts may be used when performing repairs.