Generac Power Systems 941-2, 940-2 Rocker Arm Cover Installation, Adjusting Valve Clearance

Section 2.2

VALVE TRAIN

VALVE CLEARANCE GV-220 ENGINE

INTAKE VALVE: 0.001-0.0022 inch (0.03-0.056mm) EXHAUST VALVE: 0.0018-0.003 inch (0.046-0.07mm)

Adjust the valve clearance as follows:

1.Rotate the crankshaft until the piston is at top dead center (TDC) of its compression stroke. Both valves should be closed.

2.Loosen the rocker arm jam nut.

3.Use an alien wrench to turn the pivot ball stud while checking the clearance between the rocker arm and the valve stem with a feeler gauge.

Figure 16. Adjusting Valve Clearance

4.When valve clearance is correct, hold the pivot ball stud with the alien wrench while tightening the rocker arm jam nut with a crow's foot. Tighten the jam nut to the specified torque. After tightening the jam nut, recheck the valve clearance to make sure it did not change.

JAM NUT TIGHTENING TORQUE

GV-220: 6.3 foot-pounds

Figure 17. Tightening Pivot Ball Jam Nut

Figure 18. Rocker Arm Cover Installation

ROCKER ARM COVER INSTALLATION

Place a new rocker arm cover gasket into place. Then, install the rocker arm cover. Finally, retain the cover with M6-1.00 x 12mm screws.

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