Rocker Arm Assembly: Service and Repair

Fig. 6 Camshaft sprocket & timing chain timing mark alignment. 2600cc engines:

REMOVAL

1. If rocker assembly and camshaft are being removed with cylinder head in place, proceed as follows:
a. Remove necessary hoses cables and wiring to permit rocker cover removal, then remove cover and gasket.
b. Rotate crankshaft clockwise until No. 1 cylinder is at TDC on compression stroke and camshaft sprocket timing mark and plated link on timing chain are aligned as shown in.
c. Remove distributor cap and spark plug wires, mark position of distributor rotor and installation position of distributor, then remove distributor. Do not rotate crankshaft with distributor removed.
d. Remove camshaft sprocket bolt and distributor drive gear.
e. Separate camshaft sprocket leaving timing chain on sprocket, then seat sprocket and chain assembly on sprocket holder inside timing cover. Maintain tension on chain and do not allow chain to come off sprocket. Do not rotate crankshaft with camshaft sprocket removed.

Fig. 23 Hydraulic lash adjuster & retaining clip installation. 1985-88 2000cc & 2600cc engines:

2. Evenly loosen bolts securing camshaft bearing caps in crossing pattern, then remove caps, rockers and rocker shafts as an assembly. On 1985-88 models with hydraulic lash adjusters, install suitable retainer clips over adjusters, Fig. 23, prior to removing rocker assembly.

Fig. 25 Rocker arms, rocker shafts & camshaft exploded view. 2600cc engines:

3. Remove parts in numerical order as shown, Fig. 25.

INSTALLATION

1. Insert left and right rocker shafts into front bearing cap, noting that rear end of intake shaft (left) has a notch.
2. Align mating mark of rocker arm shaft front end with mating mark of front bearing cap, then insert and tighten shaft to bearing cap attaching bolts.

Fig. 26 Rocker shaft waved washer installation. 2600cc engines:

Fig. 27 Assembling rocker arms & rocker arm shafts. 2600cc engine:

3. Install waved washers as shown, Fig. 26, then assemble rocker arm and shaft assembly as shown, Fig. 27.
4. Lubricate camshaft lobes and bearing journals with engine oil, then position camshaft on cylinder head and align camshaft so that intake and exhaust valves for No. 1 cylinder will be fully closed (TDC on compression stroke for No. 1 cylinder).

Fig. 28 Semicircular packing installation:

5. Apply sealant to O.D. of circular packing, then assemble circular packing to cylinder head as shown, Fig. 28.
6. Install rocker assembly onto cylinder head, then torque bearing cap bolts to specifications.
7. Install camshaft sprocket and timing chain assembly, and the distributor drive gear, then ensure timing marks are properly aligned and torque sprocket bolt to specifications.
8. Reverse procedure to complete installation, noting the following:
a. Install distributor, aligning matching marks made during disassembly.
b. On 1984 models, adjust valve clearances as outlined.
c. Install semi-circular packing to front of cylinder head, then apply a suitable sealant to top of packing.
d. Install rocker cover and gasket, then torque to 3.7 - 5 ft. lbs.