b. Rocker Arm Installation
Note that injector rocker arm (center rocker arm) is slightly different from exhaust rocker arms.
Boss for shaft on valve rocker arms is longer on one side of the arm than the other. The extended
boss on valve rocker arms must face injector rocker arm.
When a push rod has been disconnected from rocker arm clevis, push rod must be threaded into
clevis until end of rod is flush with, or above inner side of clevis yoke at time of reassembly,
before valve clearance is adjusted. If this is not accomplished, valve may strike piston (due to the
small clearance between valve head and piston head when piston is at top dead center) and cause
(1) Apply clean engine oil to rocker arm shafts.
(2) Install rocker arm and shaft assemblies as illustrated in Figure 5-27.
(3) Tighten rocker arm shaft bracket bolts to 50-55 lb ft torque. After tightening bolts, check for some side
clearance to prevent binding between rocker arms.
(4) Align fuel pipes and connect them. Tighten pipe nuts to 12-15 lb ft torque.
Do not bend fuel pipes and do not exceed specified torque. Excessive tightening will twist or
fracture ends of fuel pipes and result in leaks.
Fill cooling system.
Adjust exhaust valve clearance.
Adjust rocker arms.
Time fuel injectors.
Install rocker arm cover.
5-67 Rocker arm and valve adjustment
a. General. Operate engine until water temperature reaches 160° to 180°F before adjusting valve clearance. Stop
engine to make adjustment. Since adjustments are made with engine stopped, it may be necessary to run engine
between valve adjustments to prevent it from cooling off. All valve clearances can be adjusted in sequence of firing
order during one full revolution of crankshaft.
(1) Remove rocker arm cover.
(2) Adjust rocker arms as illustrated in Figure 5-29.