Contents: Sprocket of the camshaft controlling…↡ Sprocket of the camshaft controlling…↡ Intermediate shaft sprocket (engine…↡ Crankshaft sprocket ↡
Sprocket of the camshaft controlling the exhaust valves
Removal
Unscrewing the camshaft sprocket mounting bolts
Removal the sprocket from the camshaft that controls the exhaust valves
1. Remove the cylinder head cover.
2. Rotate the engine crankshaft until the 30° BTDC mark on the crankshaft pulley aligns with the side of the crankshaft angle sensor bracket.
3. Remove the upper drive chain cover.
4. Using paint, make alignment marks on the drive chain link and sprocket, then remove the sprocket mounting bolts (see fig. Unscrewing the camshaft sprocket mounting bolts). To prevent the camshaft from turning, use a wrench on the flats behind the fifth camshaft bearing cap.
5. Remove the sprocket from the camshaft (see Fig. Removing the sprocket from the camshaft controlling the exhaust valves). Remove the woodruff key or dowel pin from the front end of the camshaft.
6. Remove the sprocket from the drive chain and secure the chain, keeping it under constant tension.
Examination
1. Check the condition of the teeth on the sprocket. The teeth on the sprocket are symmetrical and if the teeth on one side are worn out, the sprocket must be replaced.
Installation
1. Check that the engine crankshaft is in a position 30° before top dead center of the piston of the first cylinder.
2. Install the woodruff key or dowel pin onto the front end of the camshaft.
3. Install the sprocket into the chain, aligning the marks made earlier.
4. Install the sprocket onto the camshaft and secure with bolts, tightening them to the required torque.
5. Install the upper chain guide and tensioner.
6. Install the cylinder head cover.
Sprocket of the camshaft controlling the intake valves
The operations for removing and installing the camshaft sprocket that controls the intake valves are part of the process for removing and installing the camshaft adjustment mechanism that controls the intake valves.
Intermediate shaft sprocket (engine 3.0)
Removal
Caution! The intermediate sprocket mounting bolt has a left-hand thread.
Removal the intermediate sprocket of the drive chain
1. Remove the upper drive chain cover.
2. Place a wrench on the flats of the camshaft behind the No.5 bearing cap and turn the camshaft controlling the intake valves counterclockwise to relieve the tension on the drive chain on the intermediate sprocket.
3. To ensure correct reinstallation of the sprocket, place a mark on the outer end of the sprocket.
4. Unscrew the intermediate sprocket mounting bolt (left hand thread) remove the sprocket and support sleeve (see Fig. Removing the intermediate sprocket of the drive chain).
Examination
1. Check the condition of the teeth on the sprocket. The teeth on the sprocket are symmetrical and if the teeth on one side are worn out, the sprocket must be replaced.
Installation
1. Install the support sleeve, intermediate sprocket and secure it with the bolt, tightening it to the required torque.
2. Using a wrench, turn the camshaft that controls the intake valves clockwise by the flats until the drive chain is tensioned on the intermediate sprocket.
3. Install the upper drive chain cover.
Crankshaft sprocket
Removal
Unscrewing the oil pump sprocket mounting bolt
Removal the oil pump sprocket
Removal the crankshaft sprocket
1. Remove the oil pan.
2. Remove the lower chain guide and tensioner shoe.
3. Place a mark on the face of the oil pump sprocket, unscrew the bolt and remove the oil pump sprocket together with the chain (see fig. Unscrewing the oil pump sprocket mounting bolt, Removing the oil pump sprocket).
4. Remove the oil pump drive chain tensioner shoe, spring and bushing from the pivot pin.
5. Place alignment marks on the drive chain link and crankshaft sprocket and remove the drive chain from the sprocket.
6. Remove the woodruff key from the front end of the crankshaft.
7. Using a puller, remove the sprocket from the crankshaft (see fig. Removing the crankshaft sprocket).
Examination
1. Check the condition of the teeth on the sprocket. The teeth on the sprocket are symmetrical and if the teeth on one side are worn out, the sprocket must be replaced.
Installation
Location of ends of oil pump drive chain tensioner spring
1. Install the woodruff key.
2. When installing a new sprocket, place alignment marks on it in the same locations as on the old sprocket.
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3. Heat the crankshaft sprocket to 50°C, align the sprocket hub groove with the woodruff key and install the sprocket onto the crankshaft. Install the drive chain onto the sprocket, aligning the marks on the sprocket and chain.
4. Install the bushing, spring and tensioner shoe onto the pivot pin.
5. Pass the oil pump drive chain around the tensioner shoe, install the sprocket with the chain on the oil pump and secure it with the bolt, tightening it to the required torque. The convex side of the sprocket should be on the oil pump side.
6. Check that the oil pump drive chain tensioner spring is installed correctly (see Fig. Location of ends of oil pump drive chain tensioner spring).
7. Install the drive chain tensioner shoe and lower chain guide.
8. Install the oil pan.