Camshaft Timing Chain, Sprocket, and Tensioner Installation SOHC

1. Assemble the timing chain, sprockets, guides and tensioner:
2. Verify that the crankshaft is positioned 90 degrees clockwise past top dead center (TDC), viewed from the accessory drive belt end of the crankshaft. The crankshaft key way sprocket timing mark must be aligned with the cylinder block main bearing cap split line to prevent piston and valve damage.



3. If required, bring the camshaft up to number one top dead center (TDC). The camshaft can be verified at TDC by loosely installing the sprocket and rotating the sprocket until the timing pin (3/16 in drill) can be installed. The dowel pin in the camshaft will be located at the 12 o'clock position. Wrench flats 21 mm (7/8 in) are installed on the camshaft to assist with rotating the cam slightly or by installing the sprocket and bolt. Only turn the camshaft clockwise to prevent intake and exhaust valve damage. The camshaft sprocket and bolt will have to be installed if the camshaft must be rotated more than a few degrees.



4. Rotate the crankshaft 90 degrees counterclockwise, (viewed from accessory drive belt end of crankshaft, up to number one TDC. The crankshaft sprocket timing mark will align with cylinder block timing mark.




Important: 

•	One silver link plate aligns with the pip mark on the camshaft sprocket and the other aligns with the crankshaft sprocket tooth that is pointed directly downward at the 6 o'clock position. The pip mark on the crankshaft sprocket must be aligned with the timing mark on the cylinder block.

•	Excess slack in the chain must be kept to the tensioner side of the cylinder block.

5. Place the timing chain over the camshaft sprocket, and under the crankshaft sprocket. Slide the camshaft sprocket onto the camshaft. The letters FRT on the camshaft sprocket must face forward away from the cylinder head.



6. Install the camshaft sprocket timing pin (3/16 in drill).




Notice: Do not torque the camshaft retaining bolts against the 3/16 in. timing pins as it will damage the cylinder head.

7. Install the camshaft washer and bolt. Wrench flats 22 mm (7/8 in) are located on the cam to hold it.

Tighten
Tighten the camshaft sprockets-to-camshafts to 100 N·m (74 lb ft).





Important: The timing chain should be snug against the fixed guide.

8. Install the fixed chain guide and check for clearance between the guide to cylinder block and head. The guide must be installed with the word FRONT facing forward away from the cylinder block.

Tighten
Tighten the timing chain fixed block-to-head to 26 N·m (19 lb ft).




9. Install the pivoting chain guide. Check for clearance between the block and head. Torque the bolt and make sure the guide pivots freely.

Tighten
Tighten the timing chain pivot guide-to-head to 26 N·m (19 lb ft).




10. Retract the tensioner plunger and pin the ratchet lever using a 3.18 mm (1/8 in No 31) drill. Install the chain tensioner and torque the two bolts. Remove the drill and allow the tensioner plunger to extend.

Tighten
Tighten the timing chain tensioner-to-block 19 N·m (168 lb in).

11. Verify all timing marks for accuracy. Remove the camshaft timing pins 4.77 mm (3/16 in) drill.



12. Camshaft timing verification procedure with engine assembled (front cover on):

12.1.

Remove the rocker cover.

12.2.

Turn the crankshaft until the mark on the crankshaft pulley aligns with the pip mark on the front cover.

Important: The camshaft sprocket timing pin hole is located below the front cover upper gasket surface and cannot be used as a reference. It may be necessary to remove the right-hand road wheel and splash shield to observe timing marks on front cover and crankshaft pulley.

12.3.

The letters FRT on the camshaft sprocket should align with the upper gasket surface of the front cover and only the pip mark on the cam sprocket should be at the 12 o'clock position. If the letters and pip mark don't align, rotate the crankshaft an additional 360 degrees. If the letters FRT and pip mark do not align, the crankshaft and camshaft are not timed.

Camshaft Timing Chain, Sprocket, and Tensioner Installation DOHC

Assemble the timing chain, the sprockets, the guides and the tensioners:

1. Verify that the crankshaft is positioned at 90 degrees past top dead center (TDC). The crankshaft keyway and sprocket must be aligned with the cylinder block main bearing cap split line, as viewed from the accessory drive end, to prevent piston and valve damage.




Notice: Do not torque the camshaft retaining bolts against the 3/16 in. timing pins as it will damage the cylinder head.

2. Install the camshaft timing gears, the retaining bolts and washers. The letters FRT on the sprockets must face forward, away from the cylinder head. Wrench flats 24 mm are provided to hold the camshafts from rotating while torquing the bolts.

Tighten
Tighten the camshaft sprockets-to-camshafts to 100 N·m (74 lb ft).




3. Bring the camshafts up to the number one TDC by rotating the camshaft and sprocket until the timing pins 4.77 mm (3/16 in) drill can be installed. Wrench flats are installed on the camshafts to assist with rotation.



4. Rotate the crankshaft counterclockwise, as viewed from the accessory drive end, until the number one cylinder is TDC. The crankshaft sprocket timing mark will align with cylinder block timing mark.




Caution: The camshaft can rotate during timing chain installation when the timing pins (4.77 mm (3/16 in) drill) have not been installed. Do not place fingers between the camshaft sprockets and the chain during the timing chain installation.

5. Place the timing chain over the camshaft sprockets and under the crankshaft sprocket.




Notice: Excess slack in the chain must be kept to the chain tensioner side (movable guide) of the cylinder block when installing the timing chain or the camshaft sprockets will not be correctly timed to the crankshaft sprocket.

Important: Two separated black link plates align the pip marks on the camshaft sprockets and another 2 paired link plates align the crankshaft sprocket tooth that is located at the six o'clock position. The pip mark on the crankshaft sprocket must be aligned with the timing mark on the cylinder block.

Important: Alignment of both timing pin holes, crankshaft sprocket pip mark with cylinder block mark, black links with camshaft and crankshaft sprockets must be correct to make sure the engine is properly timed.

6. Ensure that the black colored link plates are located over the pip mark on the cam sprockets only. The crankshaft sprocket tooth must be pointed directly downward at the 6 o'clock position between the 2 silver colored links. The pip mark on the crankshaft sprocket will be aligned with the timing mark on the cylinder block.




Important: The timing chain should be snug against the fixed guide.

7. Install the fixed guide.

Tighten
Tighten the timing chain fixed guide-to-block to 26 N·m (19 lb ft).




8. Install the pivoting chain guide. Inspect for clearance between the block and the head. Torque the bolt and ensure the guide pivots freely.

Tighten
Tighten the timing chain pivot guide-to-head to 26 N·m (19 lb ft).

Important: The camshafts must be positioned fully forward prior to bearing cap installation.

9. Install the 2 forward remaining camshaft bearing caps and timing chain guide.

Tighten
Tighten the camshaft bearing cap-to-head (LL0) to 14 N·m (10 lbs ft).




10. Retract the tensioner plunger and pin the ratchet lever using a 3.18 mm (1/8 in) or No 31 drill. Install the chain tension and torque the 2 bolts. Remove the drill and allow the tensioner plunger to extend.

Tighten
Tighten the timing chain tensioner-to-block to 19 N·m (14 lb ft).

11. Verify all timing marks for accuracy. Remove the camshaft timing pins.