GM 12556582
Timing Gear

To change the Timing Chain and sprockets, first unmount the Oil Pump and rotate the Crankshaft so that timing dots of the Crankshaft and camshaft sprockets will align and not rotate the Crankshaft assembly while the Timing Chain has been unmounted to avoid damage to the piston assemblies or valves. Then, unscrew the camshaft sprocket bolts, the camshaft sprocket, and the Timing Chain. Apply the j8433 (Two Jaw Puller), j41816-2 (Crankshaft End Protector), as well as the j41558 (Crankshaft Sprocket Remover) and remove the Crankshaft sprocket, followed by the removal of the Crankshaft sprocket itself and the Crankshaft sprocket key if required. If necessary, clean and check the Timing Chain and sprockets. For installation, the first step is to install the key in the Crankshaft kayway, tap it in until both ends are seated. Then, mount the Crankshaft sprocket on the front of the Crankshaft, aligning the Crankshaft key with the sprocket keyway, and using the j41665 (Crankshaft Balancer and Sprocket Installer) to seat the sprocket fully against the Crankshaft flange. Rotate the Crankshaft sprocket to 12 o'clock position, and that the camshaft sprocket locating pin is aligned with camshaft sprocket alignment hole and teeth of sprocket and Timing Chain are meshed correctly. Discover the camshaft sprocket mark at the 6 o'clock position, then mount the camshaft sprocket & timing chain as needed to fit the timing marks. Lastly, install the cam shaft sprocket bolts with 35 nm (26 ft. Lbs) and reinstall the Oil Pump.

To service and repair the Crankshaft Gear/sprocket as well as replace the Timing Chain and sprockets workers must have these tools: engine technicians need four tools to perform Crankshaft Gear/sprocket replacement and Timing Chain repairs: pulley puller (J8433), crankshaft sprocket remover (J41558), crankshaft balancer and sprocket installer (J41665), and crankshaft end protector (J41816-2). Pulley puller (J8433), crankshaft sprocket remover (J41558), crankshaft balancer and sprocket installer (J41665), and crankshaft end protector (J41816-2). Start the procedure by taking out the Oil Pump followed by removal of camshaft sprocket bolts (206) and sprocket (205) and Timing Chain (208). Move on to remove bolts numbered 231 together with chain guide 232. Begin the crankshaft sprocket removal with the pulley puller (J8433), crankshaft end protector (J41816-2), and crankshaft sprocket remover (J41558). Then follow by withdrawing the crankshaft sprocket key as needed. An inspection of the Timing Chain and sprockets must precede their installation process. First reinstall the key into the crankshaft keyway before using tool (122) for key tapping from both sides until proper seat is achieved. Use crankshaft balancer and sprocket installer (J41665) to properly position the crankshaft sprocket on the crankshaft front where it must align crankshaft key with sprocket keyway. Turn the crankshaft sprocket to line up its alignment mark directly at the top position. Fasten the Timing Chain Guide (232) together with its bolts (231) until they achieve 25 nm (18 ft. Lbs.) torque while keeping bolt tops even with or below the guide surface. To install the camshaft sprocket properly you should position it correctly onto the camshaft locating pin alongside verifying that the sprocket teeth interlock with the Timing Chain then you must position the camshaft and crankshaft sprocket timing marks to align their respective alignment marks at the 6 o'clock position. Set the camshaft sprocket (205) and Timing Chain (208) into place while adjusting either the camshaft or crankshaft sprockets until the timing marks match up. Then bolt the camshaft sprocket (206) with a torque of 25 nm (18 ft. Lbs.). Check how the camshaft matches up with the crankshaft sprocket timing marks (1, 2) as the final step before reinstalling the Oil Pump.

To remove the timing chain, crankshaft sprocket, camshaft position actuator and solenoid valve you have to first remove the Oil Pump and Starter motor while the teeth of the j 42386-a ( Flywheel Holding Tool ) engage with the engine Flywheel. Mount the j 42386-a with one m10-1.5 x 120 mm and one m10-1.5 x 45 mm bolt and tighten to 50 nm (37 lb ft). Rotate crankshaft until the timing marks on crankshaft and camshaft sprockets match one another, be careful not to rotate the crankshaft assembly once the timing chain removed. Next, take out the camshaft sprocket bolt (206), camshaft sprocket (205), timing chain (208), timing chain tension bolts (231), and tensioner (232). Remove the crankshaft sprocket (207) and its key if necessary, using the j 41816-2 (Crankshaft End Protector), j 41558 (Crankshaft Sprocket Remover), bolts, and j 8433 (Puller Bar). For installation, locate the key (122) in crankshaft keyway and tap until both ends of the key are seated and install the crankshaft sprocket (207) to align with the keyway. Using the j 41478 (Crankshaft Front Oil Seal Installer) and j 41665 (Crankshaft Balancer and Sprocket Installer) positions the sprocket into the crankshafts flange. Compress the Timing Chain Tensioner and install en 46330 (Timing Chain Tensioner Retaining Pin) followed by the Timing Chain Tensioner (232) and bolts (231) with 25 nm (18 lb ft). Allow the sprocket teeth to emulate for camshaft and crankshaft sprockets along with the alignment marks, if any. Install camshaft sprocket (205) in the 6 o'clock and attach it to timing chain (208) along with the bolt (206) and check for the correct alignment. Remove the en 46330 tighten the camshaft sprocket bolt firstly to 90 nm (66 lb ft) and then to turn an additional 40 degrees using j 45059 (Angle Meter). Lastly, uninstall the j 42386-a and bolts and reinstall the Starter motor, and the Oil Pump.

Begin by eliminating the Oil Pump followed by Crankshaft rotation for alignment with Crankshaft and camshaft sprocket timing marks before performing any further work since post-timing chain removal Crankshaft movement endangers piston assemblies and valves. Start by removing the camshaft sprocket bolts then move to disconnect the camshaft sprocket and Timing Chain. A three-jaw puller (J 8433) along with a Crankshaft end protector (J 41816-2) and Crankshaft sprocket remover (J 41558) should be used to detach the Crankshaft sprocket. After sprocket removal, remove the Crankshaft sprocket key if present. A thorough cleaning process should precede sprocket inspecting before you install either component. Index the Crankshaft key in its keyway before tapping both ends to proper position. Position the Crankshaft sprocket at the Crankshaft front by matching the Crankshaft key with the sprocket keyway before fully locking it into position using the j 41665 Crankshaft balancer and sprocket installer (J 41665). Rotate the Crankshaft sprocket until the alignment mark is at the 12 o'clock position, ensuring the camshaft sprocket locating pin aligns with the camshaft sprocket alignment hole, and that the sprocket teeth mesh with the Timing Chain. Align the camshaft and Crankshaft sprocket marks by positioning the camshaft sprocket alignment mark at the 6 o'clock position before installing both sprocket and Timing Chain. Before tightening the camshaft sprocket bolts to 35 nm (26 ft. Lbs.), users can rotate the camshaft or Crankshaft sprockets to achieve proper timing mark alignment. Finally, reinstall the Oil Pump.

Before starting the exchange of the timing chain and crankshaft sprocket with camshaft position actuator and solenoid valve replacement workers must remove the Oil Pump and Starter motor while ensuring the j 42386-a (Flywheel Holding Tool) teeth properly fit the engine Flywheel. Install the j 42386-a (Flywheel Holding Tool) and bolts by using one m10-1.5 x 120 mm and one m10-1.5 x 45 mm bolt then torque them to 50 nm (37 lb ft). Use the crankshaft sprocket to rotate it until the alignment marks between the cmp actuator and crankshaft sprocket become visible. To begin disconnect the cmp actuator solenoid valve (234), separate the cmp actuator (235) from the timing chain (208) while maintaining the reluctor wheel's original position. The timing chain and cmp actuator must be separated while securing a tie strap from the actuator center to the reluctor wheel to prevent damage. Grasp the crankshaft sprocket (207) and key if needed using the j 41816-2 (Crankshaft End Protector), j 41558 (Crankshaft Sprocket Remover), bolts , and j 8433 (Puller Bar). Remove the timed components with these tools after releasing the timing chain tension bolts (231) and tensioner (232). Installation begins by inserting key (122) into the crankshaft keyway, letting it tap in before mounting the crankshaft sprocket (207) to the crankshaft and matching the key position with the sprocket keyway. Use j 41478 (Crankshaft Front Oil Seal Installer) together with j 41665 (Crankshaft Balancer and Sprocket Installer) to carefully push the sprocket into its complete seat. Slip the en 46330 (Timing Chain Tensioner Retaining Pin) between the Timing Chain Tensioner guide while in its compressed state. The Timing Chain Tensioner (232) should be installed manually along with bolts (231), where torque must reach 25 nm (18 lb ft). Set the cmp actuator onto the camshaft's locating pin while maintaining correct sprocket mesh with alignment marks in position. Reinstall the cmp actuator (235) with the timing chain (208) in place without moving the reluctor wheel position. Check that the timing chain sits inside the engine block area during inspection. Fix a new cmp actuator valve (234) while tightening it securely then inspect all sprocket alignments. Perform the removal of en 46330 followed by applying 65 nm (48 lb ft) torque to the cmp actuator solenoid valve in the first operation and another additional 90-degree turn during the final stage using the j 45059 (Angle Meter). To complete the procedure detach the j 42386-a and bolts before installing the Starter motor alongside the Oil Pump.

To remove the timing chain, crankshaft sprocket, camshaft position actuator and solenoid valve you have to first remove the Oil Pump and Starter motor while the teeth of the j 42386-a ( Flywheel Holding Tool ) engage with the engine Flywheel. Mount the j 42386-a with one m10-1.5 x 120 mm and one m10-1.5 x 45 mm bolt and tighten to 50 nm (37 lb ft). Rotate crankshaft until the timing marks on crankshaft and camshaft sprockets match one another, be careful not to rotate the crankshaft assembly once the timing chain removed. Next, take out the camshaft sprocket bolt (206), camshaft sprocket (205), timing chain (208), timing chain tension bolts (231), and tensioner (232). Remove the crankshaft sprocket (207) and its key if necessary, using the j 41816-2 (Crankshaft End Protector), j 41558 (Crankshaft Sprocket Remover), bolts, and j 8433 (Puller Bar). For installation, locate the key (122) in crankshaft keyway and tap until both ends of the key are seated and install the crankshaft sprocket (207) to align with the keyway. Using the j 41478 (Crankshaft Front Oil Seal Installer) and j 41665 (Crankshaft Balancer and Sprocket Installer) positions the sprocket into the crankshafts flange. Compress the Timing Chain Tensioner and install en 46330 (Timing Chain Tensioner Retaining Pin) followed by the Timing Chain Tensioner (232) and bolts (231) with 25 nm (18 lb ft). Allow the sprocket teeth to emulate for camshaft and crankshaft sprockets along with the alignment marks, if any. Install camshaft sprocket (205) in the 6 o'clock and attach it to timing chain (208) along with the bolt (206) and check for the correct alignment. Remove the en 46330 tighten the camshaft sprocket bolt firstly to 90 nm (66 lb ft) and then to turn an additional 40 degrees using j 45059 (Angle Meter). Lastly, uninstall the j 42386-a and bolts and reinstall the Starter motor, and the Oil Pump.