Generac Power Systems GN190H, Руководство по обслуживанию и ремонту

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2. Install the valve spring washers, valve springs and valve
spring retainers over the valve guides.
a. Hold the valves with your fingers and use your thumbs to
compress the spring (see Figure 9.12).
b. When the spring has been compressed sufficiently, slide
the retainer’s small opening over the valve stem and release
the spring.
3. After both valves have been properly installed, position a new
head gasket and install the cylinder head.
NOTE: The head gasket is coated with a special sub-
stance for better sealing. It must be free of nicks, scratches
and other defects, or leakage will result.
4. Install the cylinder head bolts and tighten them in the
sequence shown in Figure 9.13 and to the first torque spec-
ification listed below. Then, tighten in the same sequence
again to the second torque specification.
TORQUE SPECIFICATION
CYLINDER HEAD BOLTS — First Sequence
• TORQUE = 15 foot-pounds or 180 inch-pounds
CYLINDER HEAD BOLTS — Second Sequence
• TORQUE = 22 foot-pounds or 264 inch-pounds
Figure 9.13 — Head Bolt Tightening Sequence
5. Position the push rod guide plate on the head. Install the
rocker arm and pivot ball stud. Install the jam nut far enough
to hold the guide plate in position. Valve clearance will be
adjusted later.
6. Install the push rod with either end resting on the tappet
(Figure 9.15).
a. Place the push rod between the guide plate tabs, then place
the rocker arm onto the end of the push rod.
b. Push rod alignment is correct when the push rod ball rests
in the rocker arm socket.
Installation of valve train parts is now complete. Valve clearance
must be adjusted before the rocker arm cover is installed.
Figure 9.14 — Install Rocker Arm and Pivot Ball Stud
Figure 9.15 — Installing the Push Rods
SECTION 9: VALVE TRAIN
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