Cylinder Head Assembly: Specifications
CYLINDER HEAD SPECIFICATIONS:Torque Specifications:
V6 Cylinder Head Bolt-Tightening Sequence:
Tighten Bolts In A 2 Step Process:
1st Step: 68 Nm (50 ft. lbs.)
2nd Step: 143 Nm (105 ft. lbs.)
INTAKE MANIFOLD SPECIFICATIONS:
Plenum Pan Bolts
Tighten the bolts, in sequence, as follows:
^ Step 1-Tighten bolts to 2.7 Nm (24 inch lbs.) torque.
^ Step 2-Tighten bolts to 5.4 Nm (48 inch lbs.) torque.
^ Step 3-Tighten bolts to 9.5 Nm (84 inch lbs.) torque.
^ Step 4-Check that all bolts are tighten to 9.5 Nm (84 inch lbs.) torque.
Manifold Bolts
Install the intake manifold bolts and tighten as follows:
^ Step 1-Tighten bolts 1 and 2 to 8 Nm (72 inch lbs.) torque. Tighten in alternating steps 1.4 Nm (12 inch lbs.) torque at a time.
^ Step 2-Tighten bolts 3 through 12, in sequence, to 8 Nm (72 inch lbs.) torque.
^ Step 3-Check that all bolts are tighten to 8 Nm (72 inch lbs.) torque.
^ Step 4-Tighten all bolts, in sequence, to 16 Nm (12 ft. lbs.) torque.
^ Step 5-Check that all bolts are tighten to 16 Nm (12 ft. lbs.) torque5.4 Nm (48 inch lbs.) torque.
^ Step 3-Tighten bolts to 9.5 Nm (84 inch lbs.) torque.
EXHAUST MANIFOLD SPECIFICATIONS:
To Head Bolts/Nuts 34 Nm (25 ft. lbs.)
To Exhaust Pipe 26 Nm (19 ft. lbs.)
CAMSHAFT GEAR/SPROCKET SPECIFICATIONS:
Mounting Bolt 68 Nm (50 ft. lbs.)
CYLINDER HEAD BOLT RE-USABILITY:
1. 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:
Inspect all surfaces with a straightedge if there is any reason to suspect leakage. If out-of-flatness exceeds 0.00075 mm/mm (0.00075 inch/inch) times the span length in any direction, either replace head or lightly machine the head surface.
FOR EXAMPLE:-A 305 mm (12 inch) span is 0.102 mm (0.004 inch) out-of flat. The allowable out-of-flat is 305 x 0.00075 (12 x 0.00075) equals 0.23 mm (0.009 inch). This amount of out-of-flat is acceptable.
The cylinder head surface finish should be 1.78-3.00 microns (70-125 microinches).