Generac Power Systems OHVI GSH 190, Service Manual, Page: 28 / 72

SeCTIoN 6: CYlINder HeAd ANd vAlveS
6-
INTAKE
VALVE
EXHAUST
VALVE
Figure 6-12. Intake and Exhaust Valves
1
2
3
4
Figure 6-13. Head Bolt Tightening Sequence
ROCKER
ARM
JAM NUT
PIVOT
BALL
STUD
PUSH ROD
GUIDE PLATE
Figure 6-14. Install Rocker Arm and Pivot Ball Stud
Figure 6-15. Install Push Rods
AdjuSTING vAlve CleArANCe
Adjust valve clearance with the engine at room temperature.
The piston should be at top dead center (TDC) of its compres-
sion stroke (both valves closed). Adjust valve clearance as
follows:
. Loosen the rocker arm jam nut. Use an allen wrench to
turn the pivot ball stud while checking the clearance
between rocker arm and valve stem with a feeler gauge
(see Figure 6-6). Refer to "SPECIFICATIONS" in the back
of this manual for proper clearance.
2. When clearance is correct, hold the pivot ball stud with
the allen wrench and tighten the rocker arm jam nut to
the specified torque with a crow's foot. After tightening
the jam nut, recheck valve clearance to make sure it did
not change.
0.076mm (0.003”)
GAUGE
Figure 6-16. Adjusting Valve Clearance
0C1103Arev0.indd 4 6/22/2006 10:50:41 AM