GM 24506089
Camshaft Gear

Open the front cover of the engine to change the timing chain, sprockets or tensioner. Position the #1 Piston at top dead center (#4 firing position) and align the mark on the camshaft sprocket with the timing mark on the bottom of the timing chain dampener . Take of the camshaft sprocket bolt and after the camshaft sprocket follow by the timing current and the timing chain dampener. If the sprocket is not easy to remove, you can gently tap the bottom edge of it using the plastic mallet to knock it loose. Use the j 5825- a (Crankshaft Gear Puller). Pull off the crankshaft sprocket. For installation, apply the j 38612 (Crankshaft Sprocket Installer) to install a crankshaft sprocket with a prelude gm p/n 1052365 or an equivalent on the crankshaft sprocket thrust surface. Install the timing chain dampener and bolt with a torque of 21 nm (15 ft. Lbs.). Line up the crankshaft timing mark with the timing mark at the top of the timing chain dampener . While supporting the camshaft sprocket with timing chain hanging toward the bottom, fit the timing chain to the crankshaft gear. Set the timing mark on the camshaft gear with the timing mark on top of timing chain dampener and make sure the dowel in the camshaft fits the dowel hole in the camshaft sprocket. Mount the camshaft sprocket on the camshaft with the help of the mounting bolt, oil the crankshaft and camshaft sprocket using engine oil and tighten the camshaft sprocket bolt to 140 nm (103 ft. Lbs.). At last, replace the engine front cover.

Standard procedure to replace a timing chain and its associated sprockets and tensioner starts with removing the engine front cover. Position the #1 Piston at top dead center (#4 firing position) and align the mark on the camshaft sprocket with the timing mark on the bottom of the timing chain dampener . Start by removing the camshaft sprocket bolt then the camshaft sprocket followed by removing the timing chain and timing chain dampener. A gentle blow with a plastic mallet on the sprocket's lower edge will help loosen it if removal proves difficult. Use crankshaft gear puller (J5825-A) to extract crankshaft sprocket. To install the crankshaft sprocket apply prelude gm p/n 1052365 or equivalent to the crankshaft sprocket thrust surface then use the crankshaft sprocket installer (J38612) as directed. Fit the timing chain dampener followed by tightening its bolts to 21 nm (15 ft. Lbs.). Place the crankshaft timing mark opposite the timing mark appearance on the bottom surface of the timing chain dampener . After holding the camshaft sprocket in place with the timing chain below, mount the timing chain on the crankshaft gear. Place the timing mark from the camshaft gear so it matches the timing mark on top of the timing chain dampener while also making sure the camshaft dowel slides into its dedicated hole in the camshaft sprocket. Use the fitting bolt to place the camshaft sprocket in position on the camshaft before applying engine oil to both sprockets followed by a 140 nm (103 ft. Lbs.) bolt torque. As the final step install the engine front cover.

Align the crankshaft timing mark with the timing mark on the bottom of the timing chain dampener and align the timing mark on the camshaft gear with the timing mark on the top of the chain dampener.