GM 24577247
Timing Chain

Anyone replacing the Timing Chain and sprockets should begin by taking away the engine front cover together with the Crankshaft position sensor's reluctor ring. Install a 1 inch long 7/16-20 x 1 inch bolt into the Crankshaft end for rotation but never use this bolt as the Crankshaft balancer bolt or extend beyond one inch to prevent damage. The Crankshaft needs to be rotated for the timing marks on both sprockets to become aligned when the number four cylinder reaches top dead center (TDC) of compression stroke position. Begin by uninstalling the camshaft sprocket bolts then proceed to take out both the camshaft sprocket and camshaft Timing Chain. Use Crankshaft gear remover tool j 5825-a to remove Crankshaft sprocket before extracting Crankshaft balancer key. First clean all components then check the camshaft Timing Chain together with both sprockets for any signs of wear or damage. When installing the Crankshaft balancer key should be placed into the Crankshaft keyway while keeping it both parallel and gently angled upward. Use the Crankshaft gear installer (J 5590) to align the keyway on the Crankshaft sprocket with the balancer key before installation. Install the camshaft sprocket with its alignment mark facing the 6 o'clock position as you position the Crankshaft sprocket toward 12 o'clock. Secure the camshaft sprocket bolts at 25 nm (18 ft. Lbs.) before replacing the Crankshaft position sensor reluctor ring by directing its keyway towards the balancer key while using the Crankshaft gear installer (J 5590) for complete insertion. Now install the engine front cover by finished installing the Crankshaft bolt.

The alignment mark should be at the 6 o'clock position, ensuring the crankshaft sprocket is at the 12 o'clock position.