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Home >> Subaru >> 1998 >> Impreza RS Coupe AWD F4-2.5L DOHC >> Repair and Diagnosis >> Specifications >> Mechanical Specifications >> Engine >> Cylinder Head Assembly >> System Specifications >> Torque Specifications
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Torque Specifications

Cylinder Head Components











Cylinder Head Removal and Installation

Cylinder Head Bolt Removal Sequence:






Cylinder Head Bolt Installation Sequence:






1. Apply a coat of engine oil to washers and bolt threads.
2. Tighten all bolts to 29 Nm (3.0 kg-cm, 22 ft. lbs.) in alphabetical sequence. Then tighten all bolts to 69 Nm (7.0 kg-cm, 51 ft. lbs.) in alphabetical sequence.
3. Back off all bolts by 180° first; back them off by 180° again.
4. Tighten all bolts to 39 Nm (4.0 kg-cm, 29 ft. lbs.).
5. Tighten all bolts by 80° to 90° in alphabetical sequence.
6. Further tighten all bolts by 40° to 45° in alphabetical sequence.

CAUTION: Do not tighten bolts more than 45°.

7. Tighten bolts (A) and (B) by 40° to 45°.

CAUTION: Ensure that the total "re-tightening angle" [in the two previous steps] do not exceed 90°.
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