Diesel Data: Automotive Repair

Timing Chain Replacement

Fig. 12 Measuring timing chain stretch:





1. Remove timing chain cover as described under ``Timing Chain Cover, Replace.''
2. Before removing timing chain, check timing chain stretch as follows:
a. Rotate crankshaft until one of the three camshaft sprocket bolts is located at top of crankshaft and camshaft center lines.
b. Using a suitable size socket and torque wrench, apply torque in direction of crankshaft rotation to the camshaft sprocket bolt, Fig. 12. Apply 30 ft. lbs. of torque if cylinder head is installed on engine and 15 ft. lbs. of torque if cylinder head is removed from engine. Do not allow engine to turn while applying torque.
c. Hold a ruler alongside a link in the chain and apply same torque as described previously in opposite direction and note amount of chain movement, Fig. 12. If movement exceeds 1-8 inch, timing chain must be replaced.
3. Remove camshaft sprocket attaching bolts, sprocket and chain.


Fig. 13 Crankshaft sprocket removal:




Fig. 14 Timing mark alignment:





4. Remove crankshaft sprocket using tools C-4760 (adapter) and C-3894-A (puller) or equivalent, Fig. 13.
5. Align crankshaft sprocket with key and drive firmly onto crankshaft.
6. Loosely install camshaft sprocket onto camshaft.
7. Rotate crankshaft and camshaft until timing marks on both sprockets are on a line passing through crankshaft and camshaft center lines, Fig. 14.
8. Remove camshaft sprocket without disturbing timing marks, then reinstall sprocket and timing chain making sure marks are aligned as described previously.
9. Install camshaft sprocket bolts and torque to 113 inch lbs.
10. Reverse remainder of procedure to assemble.