Timing Chain and Sprockets Cleaning and Inspection

WARNING: This page is about a different car, the 2004 GMC Envoy XUV, 2004 GMC Envoy XL, 2004 Chevrolet TrailBlazer, and 2004 Buick Rainier. However, it is still accessible from the selected car via links, so may be relevant.

Clean the components with cleaning solvent.

CAUTION: Refer to Safety Glasses Caution in Cautions and Notices.

Dry the components with compressed air.

Fig 1: View Of Camshaft & Crankshaft Sprockets Timing Marks Aligned

Courtesy of GENERAL MOTORS CORP.

Inspect the timing chain for binding or wear.

Fig 2: Identifying Damaged Sprocket Teeth

Courtesy of GENERAL MOTORS CORP.

Inspect the camshaft and crankshaft sprockets for:
- Worn teeth (1)
- Damaged teeth (2)
- Chipped teeth (3)
- Worn valleys between the sprocket teeth

Fig 3: View Of Crankshaft Sprocket

Courtesy of GENERAL MOTORS CORP.

Inspect the crankshaft sprocket keyway for wear.
Inspect the crankshaft sprocket oil pump drive splines for wear.