Setting Camshaft Timing

SETTING CAMSHAFT TIMING

Setting camshaft timing is necessary whenever the cam drive system has been disturbed such that the relationship between any chain and sprocket has been lost. Even when only one sprocket is involved the following procedure should he observed since one crankshaft rotation will not provide conditions where correct timing can be confirmed.

Setting Camshaft Timing:

The camshafts and crankshaft events are correctly timed when the relationships shown exists. The following procedure explains how to establish this condition. Correct timing exits when the crank sprocket and intermediate shaft sprocket have their timing marks aligned and all four camshaft drive pins are perpendicular (90°) to the cylinder head surface.

1. Remove the following components to allow access:
^ Both cam covers.
^ Front cover.
^ Three chain tensioners (tensioners may he in their installed positions but must be fully retracted).
^ Oil pump

Camshaft Secondary Drive Chain:

Primary Chain Tensioner:

2. Primary and secondary chain guides should he reinstalled if previously removed.
3. Rotate crankshaft until sprocket drive key is at approximately the 1 o'clock position. Use J 39946 to rotate crankshaft.

Setting Camshaft Timing:

4. Install the crankshaft and intermediate shaft sprockets to the primary drive chain with their timing marks adjacent to each other.
5. Install crank and intermediate sprockets over their respective shafts.
6. Rotate the crankshaft as necessary to engage the crankshaft key in the sprocket without changing the relationship of the timing marks to each other. Use J 39946 to rotate crankshaft.
7. Install intermediate sprocket retainer bolt. Tighten bolt to 60 Nm (44 lbs. ft.).

Primary Chain Tensioner:

8. Install primary chain tensioner or release tensioner shoe.
^ Tighten tensioner mounting bolts to 25 Nm (18 lbs. ft.).
9. Install flywheel holder J 39411 to lock crankshaft in this position. If engine is on a stand an alternate method should be devised.
10. Route secondary drive chain for LH cylinder head over inner row of intermediate shaft teeth.

Setting Camshaft Timing:

11. Route secondary drive chain over chain guide and install exhaust cam sprocket to chain such that camshaft drive pin engages the sprocket notch marked LE (left head exhaust). There should be no slack in the lower section of the chain and the cam drive pin must be perpendicular to the cylinder head face.

IMPORTANT: The RE (right head exhaust) cam sprocket must contain the cam position sensor pick-up.

Setting Camshaft Timing:

Rotating Camshaft:

12. Install the intake cam sprocket into the chain so that the sprocket notch marked LI (left head intake) engages the cam drive pin while the pin remains perpendicular to the cylinder head face. A hex is cast into the camshafts behind the lobes for cylinder 1 (or 2, LH) so that an open end wrench may be used to provide minor repositioning of the cams.
13. Loosely install exhaust cam sprocket retainer bolt.
14. Loosely install intake cam sprocket retainer bolt.
15. Install chain tensioner or release tension on shoe.
^ Tighten tensioner mounting bolts to 25 Nm (18 lbs. ft.).
^ Tighten cam sprocket bolts to 120 Nm (90 lbs. ft.).
16. Route secondary drive chain for RH cylinder head over outer row of intermediate shaft teeth and repeat steps 11 through 15 for RH cams. RH cam sprockets are identified RI (right intake) and RE (right exhaust). In addition the RE sprocket must contain the cam position sensor pickup.