Method of fastening intake manifold in internal combustion engine having two cylinder banks

摘要

A method of fastening an intake manifold to cylinder heads of an internal combustion engine having two cylinder banks in order to reduce the deformations of cylinder bores in the cylinder heads. The method includes steps of (1) temporarily fastening the cylinder heads to the cylinder block using cylinder head bolts with a fastening torque of 1.0 kgfm (9.8 Nm), (2) temporarily fastening the intake manifold to the cylinder heads using intake-manifold bolts with a fastening torque of 1.6+/-0.1 kgfm (15.7+/-0.98 Nm), (3) loosening the fastening torque of the int-manif. bolts up to 0 kgfm (0 Nm; see h of FIG. 3), (4) fixing the cylinder heads to the cylinder block using the cylinder head bolts with a fastening torque of e.g. 3.0 kgfm+60 DEG (29.4 Nm+60 DEG ) and (5) fixing the intake manifold to the cylinder heads using the intake-manifold bolts with a fastening torque of 0.9+/-0.1 kgfm (8.8+/-0.98 Nm).