Lash Adjuster, Camshaft, and Bearing Cap Installation

Fig 1: Intake & Exhaust Camshaft, Bearing Cap & Lash Adjuster Components (LKW)

Courtesy of GENERAL MOTORS COMPANY

Callout	Component Name
Preliminary Procedures Lubricate the hydraulic valve lash adjusters prior to installation in the cylinder head bores. Lubricate the valve tips prior to installing the rocker arm assemblies. Lubricate the roller bearings prior to installing the rocker arm assemblies. Apply lubricant to all camshaft lobes and journals prior to installing the camshafts. Refer to Adhesives, Fluids, Lubricants, and Sealers (LTG) , Adhesives, Fluids, Lubricants, and Sealers (LKW) .
1	Dual Feed Hydraulic Valve Lash Adjuster (Qty: 8) NOTE: Pre-fill the low pressure chamber with engine oil. Maintain a vertical orientation of the assembly to retain the oil in the reservoir and high pressure chamber. Do not install the lash adjusters without pre-filling the low pressure chamber. Apply engine oil to the outer diameter surface of all adjusters.
2	Dual Lift Valve Rocker Arm Assembly (Qty: 8) NOTE: Used rocker arms must be returned to the original position on the camshaft. If the camshaft is being replaced, the rocker arms actuated by the camshaft must also be replaced. NOTE: Position the valve rocker arm on the tip of the valve stem and on the lash adjuster and lubricate. Refer to Adhesives, Fluids, Lubricants, and Sealers (LTG) , Adhesives, Fluids, Lubricants, and Sealers (LKW) .
3	Hydraulic Valve Lash Adjuster (Qty: 8) NOTE: Pre-fill the low pressure chamber with engine oil. Maintain a vertical orientation of the assembly to retain the oil in the reservoir and high pressure chamber. Do not install the lash adjusters without pre-filling the low pressure chamber. Apply engine oil to the outer diameter surface of all adjusters.
4	Valve Rocker Arm Assembly (Qty: 8) NOTE: Used rocker arms must be returned to the original position on the camshaft. If the camshaft is being replaced, the rocker arms actuated by the camshaft must also be replaced. NOTE: Position the valve rocker arm on the tip of the valve stem and on the lash adjuster and lubricate. Refer to Adhesives, Fluids, Lubricants, and Sealers (LTG) , Adhesives, Fluids, Lubricants, and Sealers (LKW) .
5	Camshaft Bearing Lower Cap
6	Camshaft Bearing Lower Cap Bolt (Qty: 7) CAUTION: Refer to Fastener Caution . Procedure Tighten the bolts in the sequence shown. Tighten 10 (89 lb in)
7	Exhaust Camshaft NOTE: Set the exhaust camshaft on top of the rocker arms in the camshaft bearing journals with the notch at the front of the camshaft in the 11 O'clock position. Ensure that the oil seal near the front of the camshaft is rotated so that the split line on the oil seal is aligned with the notch.
8	Intake Camshaft NOTE: Set the intake camshaft on top of the roller followers in the camshaft bearing journals with the notch at the front of the camshaft in the 12 O'clock position. Ensure that the oil seal near the front of the camshaft is rotated so that the split line on the oil seal is aligned with the notch.
9	Camshaft Bearing Upper Cap NOTE: To properly position the camshaft caps, install the camshaft cap bolts into the camshaft caps prior to installing the camshaft caps on the camshafts.
10	Camshaft Bearing Cap Bolt (Qty: 18) Procedure Install the camshaft cap bolts into the camshaft caps. NOTE: Use only the two outer bolts for the front upper camshaft cap. Hand install the two bolts and loosely tighten only. The remaining two bolts, the timing chain guide, and final torque are performed during the timing procedure. Install the camshaft caps and hand start the camshaft cap bolts. Tighten the camshaft cap bolts in sequence using the following procedure: Tighten the camshaft cap bolts in sequence to 8 (71 lb in). Loosen both bolts in each cap in sequence 180 degrees. Tighten the camshaft cap bolts in sequence to 10 (89 lb in) twice.
11	Camshaft Bearing Upper Cap
12	Camshaft Bearing Cap
13	Camshaft Bearing Cap