Cylinder Head Bolt Torque

CYLINDER HEAD BOLT TORQUE/SEQUENCE





Head Bolt Torque Sequence






Cylinder Head Bolt Identification


Tighten the engine cylinder head bolts in sequence according to the following procedure.

CAUTION: During the final tightening sequence, bolt No. 11 will be tightened to a lower torque than the rest of the bolts. DO NOT overtighten bolt No. 11.

a. Tighten all bolts in sequence (1 through 14) to 30 Nm (22 ft. lbs.) torque.
b. Tighten all bolts in sequence (1 through 14) to 61 Nm (45 ft. lbs.) torque.
c. Check all bolts to verify they are set to 61 Nm (45 ft. lbs.) torque.
d. Tighten bolts in sequence:
- Bolts 1 through 10 to 149 Nm (110 ft. lbs.) torque.
- Bolt 11 to 135 Nm (100 ft. lbs.) torque.
- Bolts 12 through 14 to 149 Nm (110 ft. lbs.) torque.
- All bolts are 12 point drives for rocker cover clearance
e. Check all bolts in sequence to verify the correct torque.
f. If not already done, clean and mark each bolt with a dab of paint after tightening. Should you encounter bolts which were painted in an earlier service operation, replace them.





MANIFOLDS TO HEAD PROCEDURE
Tighten the fasteners in sequence and to the specified torque.
- Fastener Nos. 1 - 5: Tighten to 33 Nm (24 ft. lbs.) torque.
- Fastener Nos. 6 - 7: Tighten to 31 Nm (23 ft. lbs.) torque.
- Fastener Nos. 8 - 11: Tighten to 33 Nm (24 ft. lbs.) torque.



CYLINDER HEAD BOLT RE-USABILITY

Cylinder head bolts should be carefully examined before reuse. If the threads are necked down, the bolts should be replaced.





NOTE: Necking can be checked by holding a scale or straight edge against the threads. If all the threads do not contact the scale, the bolt should be replaced.

CYLINDER HEAD SURFACE VARIATION

Maximum Allowable Surface Variation .008"

Use a straightedge and feeler gauge to check the flatness of the engine cylinder head and block mating surfaces.