Camshaft Gear/Sprocket: Service and Repair

REMOVAL

CAUTION: When camshaft sprocket bolts are loosened or removed, the camshafts must be re-timed to the engine. Also, the camshaft sprocket bolts must NOT be reused. Refer to camshaft timing and timing belt.

1. Hold camshaft sprocket with 36 mm (1 7/16 inch) box wrench loosen and remove bolt and washer. To remove the bolt with engine in the vehicle it may be necessary to lift that side of the engine because the right bolt is 213 mm (8 3/8 inch) long and the left bolt is 255 mm (10.0 inch) long.

2. Remove camshaft sprocket from camshaft. Each sprocket has a D shaped hole that allows it to rotate several degrees in each direction on it's shaft. This design must be timed with the engine to ensure proper performance of the engine. Refer to camshaft and timing belt.

TIMING PROCEDURE-3.2L

Figure 48-Camshaft Sprocket Identification:

CAUTION: The camshaft sprockets are not interchangeable from side to side.

Figure 49 Timing Belt System:

1. Place crankshaft sprocket to the TDC mark on the oil pump housing.

Figure 54-Dial Indicator Locating Piston At TDC:

2. Install a dial indicator in number 1 cylinder to check TDC of the piston. Rotate the crankshaft until the piston is at exactly TDC. This is important for good engine performance.

Figure 50 Camshaft Alignment Special Tools 6642:

3. Install the camshaft alignment Special Tools 6642 to the rear of each cylinder head.

CAUTION: Compress the tensioner slowly, as damage to the tensioner could result.

Figure 51 Compressing Timing Belt Tensioner:

4. Slowly pre-load the tensioner with a vise and install locking pin.

NOTE: Once pin is installed, the tensioner must be stored with the plunger facing upward until it is ready to be reinstalled.

Figure 52-Camshaft Sprocket Timing Marks:

5. Install camshaft sprockets onto the camshafts. Install NEW sprocket attaching bolts into place. The 255 mm (10 inch) bolt is to be installed in the left camshaft and the 213 mm (8 3/8 inch) bolt is to be installed into the right camshaft. Do not tighten the bolts. Camshaft sprocket mark should be positioned between the marks OI1 the cover at both sprocket.

Figure 53-Timing Belt-Installation:

6. Install the timing belt starting at the crankshaft sprocket going in a counterclockwise direction. Install the belt around the last sprocket. Maintain tension on the belt as it is positioned around the tensioner pulley. Each camshaft sprockets mark should still fall between the cover marks.
7. Holding the tensioner pulley against the belt, install the tensioner into the housing and tighten to 28 Nm (250 inch lbs.).
8. When tensioner is in place pull retaining pin to allow the tensioner to extend to the pulley bracket.

Figure 54-Dial Indicator Locating Piston At TDC:

9. With number 1 piston at TDC, hold the camshaft sprocket hex with a 36 mm (1 7/16 inch) wrench and tighten the camshaft bolts to 102 Nm (75 ft. lbs.) plus a 90 degree turn for the Right side and 115 Nm (85 ft. lbs.) plus a 90 degree turn for the Left side.
10. Remove dial indicator and install spark plug.
11. Remove camshaft alignment Special Tools 6642 and install cam covers and O-rings. Tighten fasteners to 28 Nm (250 inch lbs.).
12. Install timing belt covers. Refer to Timing Belt Cover.
13. Install crankshaft damper.
14. Install accessory drive belts. Refer to Cooling System.
15. Fill cooling system. Refer to Cooling System.
16. Start engine and allow to idle for approximately 1 minute. Then, operate the engine at speed of 1200 - 1500 RPM for 5 minutes. This will help to bleed out any possible air in the timing belt tensioner.