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