Valve Lash Adjustment

WARNING: This page is about a different variant/trim than selected.

Rotate the crankshaft to bring the number 1 cylinder at the top dead center of the compression stroke. The number 1 cylinder is the front cylinder on the right bank. The mark on the crankshaft balancer should be aligned with the mark on the engine.

Fig 1: View Of Crankshaft Balancer Mark Aligned With Engine Mark
Courtesy of GENERAL MOTORS CORP.
Loosen the valve adjusting screws.
Insert a feeler gauge between the tip of the rocker arm and the valve bridge.

Fig 2: Measuring Rocker Arm Clearance
Courtesy of GENERAL MOTORS CORP.

NOTE: Refer to FASTENER NOTICE .

Fig 3: Identifying Valves To Adjust When #1 Cylinder Is At TDC Of Compression Stroke

Courtesy of GENERAL MOTORS CORP.

Adjust the valve lash to 0.3 mm (0.012 in). Refer to Valve Clearance Adjustment Specifications to determine which valves that can be adjusted when the engine is at Top Dead Center.
Tighten: Tighten the valve lash lock nut to 22 N.m (16 lb ft).
Rotate the crankshaft one revolution to bring the number 1 cylinder at Top Dead Center of the exhaust stroke.

Fig 4: View Of Crankshaft Balancer Mark Aligned With Engine Mark
Courtesy of GENERAL MOTORS CORP.
Adjust the valve lash to 0.3 mm (0.012 in). Refer to Valve Clearance Adjustment Specifications to determine which valves that can be adjusted when the engine is at Top Dead Center.

Fig 5: Identifying Valves To Adjust When #1 Cylinder Is At TDC Of Exhaust Stroke
Courtesy of GENERAL MOTORS CORP.
Tighten: Tighten the valve lash lock nut to 22 N.m (16 lb ft).