1.2.1 Valve Operating Mechanism
DETROIT DIESEL 53
4. Align the fuel pipes and connect them to the injectors
and the fuel connectors. Tighten the fuel pipe nuts to
12-15 Ib-ft torque with socket J 8932-01.
Install Rocker Arms and Rocker Arm Shaft
CAUTION : Do not bend the fuel pipes
1. Install the cylinder head, if removed, as outlined in
Section 1.2.
and do not exceed the specified torque.
2. Apply clean engine oil to the surface of the rocker
Excessive tightening will twist or
arm shaft.
fracture the flared ends of the fuel pipes
3. Install the rocker arms and rocker arm shaft by
and result in leaks.
Lubricating oil
reversing the sequence of operations for removal.
diluted by fuel oil can cause serious
Tighten the rocker arm shaft bracket bolts to 50-55 Ib- ft
damage to the engine bearings.
torque. After tightening the bolts, check for some side
clearance to prevent bind between the rocker arms.
5. Fill the cooling system.
CAUTION : There is a possibility of
6. Adjust the exhaust valve clearance and time the fuel
damaging the exhaust valves if the valve
injector as outlined in Section 14.1 and 14.2 before
bridges are not resting on the ends of
starting the engine.
the valves when tightening the rocker
7. Start the engine and check for leaks in the fuel,
arm shaft bracket bolts (Fig. 12).
cooling and lubrication systems.
Therefore, note the position of the
8. Tune-up the engine, as outlined in Section 14, after
exhaust valve bridges before, during and
the engine reaches normal operating temperature.
after tightening the rocker arm shaft
bracket bolts.
1972 General Motors Corp.
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