Timing Chain: Service and Repair

Timing Chain and Sprockets Replacement

- Tools Required
- J 22888-20A Crankshaft Gear Puller
- J 5590 Crankshaft Gear Installer

Removal Procedure





1. Remove the engine front cover.

Notice: In order to rotate the engine install a bolt with the same threads as the crankshaft, but do not use the crankshaft balancer bolt or a bolt longer than 1 inch, in the crankshaft. Failing to do so will cause damage to the bolt threads and the crankshaft threaded hole when removing the bolt.

2. Install a bolt in the end of the crankshaft.

Notice: Align the timing marks before removing the timing chain. If it is necessary to turn either the camshaft or the crankshaft with the timing chain removed, loosen or remove the valve rocker arms. Turning either the crankshaft or camshaft with the timing chain removed may cause the pistons to contact the valves, resulting in damage.

3. Rotate the crankshaft until the number 1 piston is at Top Dead Center (TDC) of the compression stroke.
Make sure the camshaft sprocket alignment mark, which is an 8 mm (0.31 inch) hole, and the stamped circle in the crankshaft sprocket align with the tabs on the timing chain tensioner.





Important: Before removing the timing chain, measure the distance between the hole in the bracket and the unworn surface of the timing chain tensioner shoe.
If the distance between the hole and the unworn surface of the timing chain tensioner shoe is more than 8 mm (0.314 inch), replace the tensioner, timing chain, and both sprockets.

4. Remove the timing chain tensioner bolts.





Notice: Do not replace only the tensioner or the chain to correct a noise condition caused by the camshaft drive components. When replacing the tensioner or chain to correct a noise condition all of the camshaft drive components must be replaced.

5. Remove the timing chain, the timing chain tensioner, and the camshaft sprocket at the same time.
6. If replacing camshaft, remove the camshaft position sensor.





7. Remove the crankshaft sprocket. Use the J 22888-20A.
8. Clean and inspect the timing chain and sprockets.


Installation Procedure

Important: If any of the camshaft drive components are being replaced to correct a noise condition, replace all of the components in the camshaft drive system.

Important: Install crankshaft sprocket alignment key.
If any of the camshaft drive components are being replaced to correct a noise condition, replace all of the components in the camshaft drive system.





1. Install crankshaft sprocket alignment key.
2. Install the crankshaft sprocket using J 5590. Make sure that the crankshaft sprocket is seated against the crankshaft.
3. Install the timing chain and install the timing chain tensioner.





4. Compress the timing chain tensioner spring.
5. Insert a cotter pin or a nail into the hole in the tensioner to retain the timing chain tensioner shoe.





6. Install the timing chain tensioner. Do not tighten the timing chain tensioner bolts.





7. Align the crankshaft sprocket timing mark with the tab on the timing chain tensioner.
8. Align the camshaft sprocket timing mark with the tab on the timing chain tensioner.

Notice: Refer to Fastener Notice in Service Precautions.

9. Install the camshaft sprocket and install the timing chain.
- Tighten the timing chain tensioner bolts to 24 Nm (18 ft. lbs.).
- Tighten the camshaft sprocket bolt to 130 Nm (96 ft. lbs.).





10. Remove the cotter pin or nail from the hole in the timing chain tensioner.
11. Remove the bolt from the end of the crankshaft.
12. Install the engine front cover.