Generac — Valve Clearance Adjustment

Adjustments

From a Generac owner's manual — check it applies to your exact model before use.

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Procedure

1. Remove spark plug wire(s) and position away from plugs.
2. Remove spark plug(s).
3. Remove the four screws attaching the valve cover.
4. Remove and discard the valve cover gasket.
5. Make sure the piston is at top dead center (TDC) of its compression stroke.
6. Remove the intake screen at the front of the engine to access the flywheel nut.
7. Use a large socket and wrench to rotate the flywheel nut clockwise to position the piston at TDC.
8. Loosen the rocker jam nut using a 13 mm wrench.
9. Turn the pivot ball stud using a 10 mm Allen wrench while checking clearance.
10. Adjust clearance to 0.002–0.004 in using a feeler gauge.
11. Hold the pivot ball stud in place with a wrench and tighten the rocker arm jam nut to 174 in-lbs (19.68 Nm).
12. Recheck valve clearance to verify it did not change.
13. Install new valve cover gasket.
14. Install the valve cover and tighten fasteners in a cross pattern to 60 in-lbs (6.8 Nm).
15. Install spark plugs and torque to 18 ft-lbs (25 Nm).

Source: Generac owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.

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