Chevrolet Silverado / GMC Sierra. Service manual — part 280

Fig. 155: Identifying Alignment Hole & Locating Pin
Courtesy of GENERAL MOTORS CORP.

2. Identify the alignment hole (1) in the rear face of the CMP actuator and the locating pin (2)

on the front face of the camshaft.

IMPORTANT:

Properly locate the CMP actuator on the locating pin of
the camshaft.

The sprocket teeth and timing chain must mesh.

The camshaft and the crankshaft sprocket alignment
marks MUST be aligned properly.

DO NOT use the CMP solenoid valve again. Install a NEW
valve during assembly.

2008 Hummer H2

2008 ENGINE Engine Mechanical - 6.2L - H2

Fig. 156: Proper Installation Of CMP Actuator
Courtesy of GENERAL MOTORS CORP.

2008 Hummer H2

2008 ENGINE Engine Mechanical - 6.2L - H2

3. Install the CMP actuator and timing chain. Align the hole in the rear face of the CMP

actuator with the locating pin on the front face of the camshaft. If necessary, rotate the
camshaft or crankshaft sprockets in order to align the timing marks. Use care to install the
actuator completely onto the front of the camshaft. Position your fingers onto the face of the
actuator sprocket and push the actuator onto the front of the camshaft. Never push on the
reluctor wheel when attempting to install the actuator.

CAUTION: Do not push or pull on the reluctor wheel of the camshaft

position (CMP) actuator during removal or installation.
The reluctor wheel is retained to the front of the CMP
actuator by 3 roll pins. Pushing or pulling on the wheel
may dislodge the wheel from the front of the actuator. The
actuator return spring is under tension and may rotate the
dislodged reluctor wheel, causing personal injury.

2008 Hummer H2

2008 ENGINE Engine Mechanical - 6.2L - H2

Fig. 157: Inspecting For Proper Installation Of CMP Actuator & Timing Chain
Courtesy of GENERAL MOTORS CORP.

4. Place a straight edge across the front face of the engine block and inspect for proper

installation of the CMP actuator and timing chain. With the CMP actuator properly and
completely installed onto the front of the camshaft, the timing chain will not protrude

2008 Hummer H2

2008 ENGINE Engine Mechanical - 6.2L - H2