TM 9-2330-356-14
h.
Disconnect pressure gage from Number 1
cylinder nozzle and holder assembly. Attach fuel inlet and
return lines, and then repeat above procedures to test and
adjust Number 2 cylinder nozzle and holder assembly.
i.
Repeat step
h
for Number 3 and Number 4
cylinder nozzle and holder assemblies.
7-88. Valve Rocker Arm Adjustment
NOTE
Readjust rocker arm-to-valve clearance after
the first 50 hours of operation on a new or
rebuilt engine.
a.
Check and adjust the rocker arm to proper valve
clearance every 500 operating hours.
b.
Always check and adjust the valve tappet
clearance when the engine is at an ambient temperature
of approximately 70°F. Remove rocker cover and proceed
as follows:
CAUTION
Turn blower wheel clockwise only.
(1) Using a 5/8-inch socket wrench and extension,
turn the blower wheel clockwise until Number 1 cylinder
is on its compression stroke, which follows the closing of
its intake valve. See figure 7-80 for identification of intake
valve assembly.
(2) Continue clockwise rotation until TC (top
center) mark on flywheel lines up with timing pointer on
gear cover (fig. 7-78). Then turn flywheel in a clockwise
direction for an additional 10°-450. The timing mark for
this position must be established. In this position, the
piston will be in its power stroke with both valves
completely closed.
(3) Using a feeler gage, check the clearance
between the rocker arm and the valve stem cap (fig. 7-80).
Increase or reduce the clearance until the proper gap is
established, adjusting the lock nut which secures the
rocker arm to the cylinder head. Correct valve clearance is
0.009-inch for intake valves and 0.007-inch for exhaust
valves.
(4) To adjust the valve clearance for Number 2
cylinder, turn the blower wheel clockwise 180° until the
flywheel is 10°-450 past the BC (bottom center) mark and
adjust valves as given in step (3).
7-89. Cylinder Head Compression Test, On
Equipment
a.
Remove shroud door panel on engine to gain
access to the air intake manifold.
Figure 7-80. Checking and Adjusting Rocker Am-to- Valve Clearance.
7-69