Rocker Shafts

REMOVAL & INSTALLATION

WARNING
This operation should only be performed when the engine is cold!

1.3L, 1.4L, 1.5L and 1979–82 2.0L Engines

1. Remove the rocker arm cover, as previously described.
2. Loosen the cylinder head retaining bolts using several stages using of the sequence indicated by the illustration.

   NOTE: Although the cylinder head need not be removed, the same bolts which retain the cylinder head to the block also secure the rocker shaft assembly.

   Fig. 1: Cylinder head bolt loosening sequence — 1.3L, 1.4L, 1.5L and 1979–82 2.0L engines

   Fig. 2: Position the rocker assembly on 1979–82 2.0L engines so that the oil passages align as shown

   Fig. 3: On 1978–85 GLCs and 1979–82 626s, position the rocker assembly so that the adjusting studs are offset 0.039 in. (1mm) from the centers of the exhaust valve stems

   Fig. 4: Cylinder head bolt tightening sequence — 1.3L, 1.4L, 1.5L and 1979–82 2.0L engines

3. Remove the rocker shaft and bolts as an assembly. Stuff a rag in the drain hole to prevent the valve keepers from falling into the oil pan.

   To install:

4. Remove the rag. Align the dowels and place the rocker shaft assembly on the cylinder head.
5. Make sure that all the spherical valve operators at the outer ends of the rocker levers are positioned so that the flat surface is against the top of the valve stem.
6. Position the rocker assembly so that the exhaust valve rocker arms are offset 0.039 in. (1mm) from the centers of the valve stems (see illustration).
7. Torque the cylinder head retaining bolts using several stages of the appropriate sequence, as illustrated. For all but the 2.0L engine, tighten the bolts to 56–59 ft. lbs. (78–82 Nm). On the 1981 2.0L engine, tighten the bolts to 59–64 ft. lbs. (80–87 Nm); on the 1982 2.0L engine, tighten the bolts to 65–69 ft. lbs. (88–93.5 Nm).
8. Adjust the valve clearances, as described later in this section.
9. Install the rocker arm cover, as previously described.

1.6L, 1983–87 2.0L, and 2.2L Engines

1. Remove the cylinder head cover, as previously described.
2. Loosen the rocker shaft bolts, a little at a time, in the sequence indicated by the illustration.

   NOTE: Do not remove the rocker shaft bolts.

   Fig. 5: Rocker shaft bolt loosening sequence — 1.6L engine

   Fig. 6: Rocker shaft bolt loosening sequence — 2.2L and 1983–87 2.0L engines

   Fig. 7: If applicable, unfasten the retaining nuts and bolts . . .

   Fig. 8: . . . then remove the rear housing and gasket

   Fig. 9: Loosen (but do not withdraw) the rocker shaft bolts, then lift the shaft assembly from the head

   Fig. 10: On 2.2L and 1983–87 2.0L engines, coat each end of the cylinder head with sealer (as indicated by the shaded areas), before installing the rocker shaft assembly

   Fig. 11: After positioning the rocker shaft assembly, tighten the bolts to specification

   Fig. 12: Rocker shaft bolt tightening sequence — 1.6L engine

   Fig. 13: Rocker shaft bolt tightening sequence — 2.2L and 1983–87 2.0L engines

3. On the 2.0L engine, the rear housing and gasket may have to be removed before the rocker shaft assembly can be separated (if a stud extends from the assembly's end cap through the rear housing). If applicable, unfasten the appropriate nuts and bolts, then remove the rear housing and gasket.
4. Remove the rocker shaft assembly with the bolts. Stuff a rag in the drain hole to prevent the valve keepers from falling into the oil pan.

   To install:

5. Remove the rag. On 2.2L and 1983–87 2.0L engines, apply a thin coating of sealant to the ends of the cylinder head, as illustrated, before installing the rocker shaft assembly.
6. Position the rocker shaft assembly. Make sure that all the spherical valve operators at the outer ends of the rocker levers are situated so that the flat surface is against the top of the valve stem.
7. If applicable, position the rear housing with a new gasket, then install the retaining nuts and bolts.
8. Torque the rocker shaft bolts in two or three steps using the appropriate pattern, as illustrated. On 1986 1.6L engines, torque the bolts evenly to 14–17 ft. lbs. (19–23 Nm) in the order shown. On 1987–89 1.6L non-turbo engines, torque the bolts evenly to 16–21 ft. lbs. (22–28 Nm), using the same torque pattern as for 1986. On 2.2L and 1983–87 2.0L engines, torque the bolts evenly in the order shown to 13–20 ft. lbs. (18–27 Nm).
9. On 2.0L and 1.6L engines through 1987, adjust the valve clearances as described later in this section.
10. Install the cylinder head cover, as previously described.

3.0L Engine

NOTE: The following procedure applies to both cylinder banks.

1. Remove the cylinder head cover, as previously described.
2. Loosen the rocker shaft bolts, a little at a time, in the sequence indicated by the illustration.

   NOTE: Do not remove the rocker shaft bolts.

   Fig. 14: Rocker arm shaft loosening sequence — 3.0L engine

   Fig. 15: Rocker arm shaft tightening sequence — 3.0L engine

3. Remove the rocker shaft assembly and bolts as an assembly. Stuff a rag in the drain hole to prevent the valve keepers from falling into the oil pan.

   To install:

4. Remove the rag and position the rocker shaft assembly. Make sure all the spherical valve operators at the outer ends of the rocker levers are positioned so the flat surface is against the top of the valve stem.
5. Torque the rocker shaft bolts, in two or three steps using the illustrated sequence, to 14–19 ft. lbs. (19–26 Nm). Be careful not to catch the rocker arm shaft spring between the shaft and the mounting boss during installation.
6. Install the cylinder head cover, as previously described.