Generac Power Systems 941-2, 940-2 Valve Components Installation, Valve Guides, Valve Tappet

Section 2.2

VALVE TRAIN

NOTE: After the valve guides have been over- sized, be sure to recut the valve seats so they will align with the guides.

Figure 8. Valve Guides

VALVE TAPPETS:

Valve tappets can be removed during removal of the engine camshaft. Intake and exhaust valve tappets are identical. However, once a wear pattern has been established the two tappets should not be Interchanged.

Figure 10. Valve Tappet

VALVE SPRINGS:

Inspect the valve springs. Measure the spring free length. Also, check the amount of force required to compress the spring to a length of 1.39 inch (35.2 mm). Replace any damaged or defective spring.

Figure 10. Valve Spring

VALVE SPRING FREE LENGTH

GV-220: 2.0741inch (52.69mm)

FORCE REQUIRED TO COMPRESS SPRING TO 1.39

INCH (35.2MM)

GV-220:19.8-21.81lbs (9.0-9.9kg)

VALVE COMPONENTS INSTALLATION

After the valve train parts have been inspected and (if necessary) serviced, install them as follows:

1.Lubricate the valve stems and the valve guides with engine oil.

2.Install the intake and exhaust valves through their respective valve guides In the cylinder head.

a.The exhaust valve has the smaller head with a diameter of 1.053 inches (26.75mm).

b.The intake valve has the larger head, having a diameter of 1.171 inches (29.75mm).

c.Valve seat sizes in the cylinder head will match their respective head sizes.

NOTE: The exhaust valve stem Is also smaller than that of the Intake valve.

Figure 11. Installation of Intake and Exhaust Valves

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