Timing Chain and Sprocket Installation 6.2L LS3

Special Tools

For equivalent regional tools, refer to Special Tools

1. Install the key into the crankshaft keyway, if previously removed.



2. Tap the key (122) into the keyway until both ends of the key bottom onto the crankshaft.



3. Install the crankshaft sprocket (207) onto the front of the crankshaft. Align the crankshaft key with the crankshaft sprocket keyway.



4. Use the J 41478 installer  (1) and the J 41665 installer  (2) in order to install the crankshaft sprocket.

Install the sprocket onto the crankshaft until fully seated against the crankshaft flange.

5. Rotate the crankshaft sprocket until the alignment mark is in the 12 o'clock position.



6. Compress the timing chain tensioner guide and install the EN 46330 pin .

Caution: Refer to Fastener Caution in the Preface section.




7. Install the timing chain tensioner (232) and bolts (231). Tighten the timing chain tensioner bolts to 25 N·m (18 lb ft).




Note: 

•	The sprocket teeth and timing chain must mesh.

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

8. Install the camshaft sprocket (205), timing chain (208), and bolt (206).



9. Inspect the sprockets for proper alignment. The mark on the camshaft sprocket (1) should be located in the 6 o'clock position and the mark on the crankshaft sprocket (2) should be located in the 12 o'clock position.



10. Remove the EN 46330 pin .

Note: Do not apply threadlock to the flex plate bolts at this time.

11. Temporarily install the automatic transmission flex plate or manual transmission flywheel and bolts. Refer to Engine Flywheel Installation.



12. Install the J 42386-A holding tool and bolts. Use 1 M10-1.5 x 120 mm bolt and 1 M10-1.5 x 45 mm bolt for proper tool operation. Tighten the J 42386-A holding tool bolts to 50 N·m (37 lb ft).



13. Tighten the camshaft sprocket bolt.

•	Tighten the camshaft sprocket bolt a first pass to 75 N·m (55 lb ft) .

•	Tighten the camshaft sprocket bolt a final pass an additional 50 degrees using the J 45059 meter .

14. Remove the J 42386-A holding tool and bolts.
15. Remove the automatic transmission flex plate or manual transmission flywheel and bolts. Refer to Engine Flywheel Removal.

Timing Chain and Sprocket Installation 6.2L LS9

Special Tools

1. Install the key into the crankshaft keyway, if previously removed.



2. Tap the key (122) into the keyway until both ends of the key bottom onto the crankshaft.



3. Install the crankshaft sprocket (207) onto the front of the crankshaft. Align the crankshaft key with the crankshaft sprocket keyway.



4. Use the EN-47812 bolt  (1) and the J 41665 installer  (2) in order to install the crankshaft sprocket.

Install the sprocket onto the crankshaft until fully seated against the crankshaft flange.

5. Rotate the crankshaft sprocket until the alignment mark is in the 12 o'clock position.

Caution: Refer to Fastener Caution in the Preface section.




6. Install the timing chain tensioner (2) and bolts (1) and tighten to 25 N·m (18 lb ft).




Note: 

•	Properly locate the camshaft sprocket onto 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.

Position the camshaft sprocket alignment mark in the 6 o'clock position.

7. Install the camshaft sprocket (2) and timing chain (3). If necessary, rotate the camshaft or crankshaft sprockets in order to align the timing marks.



8. Inspect the sprockets for proper alignment. The mark on the camshaft sprocket (1) should be located in the 6 o'clock position and the mark on the crankshaft sprocket (2) should be located in the 12 o'clock position.
9. Install the camshaft sprocket bolts and tighten to 30 N·m (22 lb ft).