Timing Belt: Service and Repair

REMOVAL





1. Remove the crankshaft pulley, coolant pump pulley and drive belt.





2. Remove the timing belt cover.





3. Remove the timing belt tensioner pulley.
4. Remove the timing belt.





NOTE: If the timing belt is reused, make an arrow indicating the turning direction (or the front of the engine) to make sure that the belt is reinstalled in the same direction as before.

5. Remove the idler pulley.





6. Remove the camshaft sprocket.

NOTE: Be careful not to damage the cylinder head with the wrench.

7. Remove the crankshaft sprocket from crankshaft.

INSPECTION
Sprockets and Tensioner pulley, and Idler pulley
1. Check the camshaft sprocket, crankshaft sprocket, tensioner pulley, and idler pulley for abnormal wear, cracks, or damage. Replace as necessary.





2. Inspect the tensioner pulley and the idler pulley for easy and smooth rotation and check for play or noise. Replace as necessary.
3. Replace if there is a new grease leak.

Timing belt





1. Check the belt for oil or dust deposits. Replace if necessary. Small deposits should be wipe away with a dry cloth or paper. Do not clean with solvent.
2. When the engine is overhauled or belt tension adjusted, check the belt in detail. If the following flaws are evident, replace the belt with a one.

Description





1. Hardened back surface rubber





2. Cracked back surface rubber





3. Cracked or separated canvas





4. Badly worn teeth (initial stage)





5. Badly worn tooth (last stage)





6. Cracked tooth bottom





7. Missing tooth





8. Side of belt badly worn





9. Side of belt cracked

Flaw conditions
Back surface glossy. Non-elastic and so hard that when a fingernail is forced into it, no mark is reduced.
Canvas on load side tooth flank worn (Fluffy canvas fibers, rubber gone and color changed to white, and unclear canvas texture)
Canvas on load side tooth flank worn down and rubber exposed (tooth width reduced)

NOTE: Normal belt should have precisely cut sides as if produced by a sharp knife.

INSTALLATION





1. Install the flange and crankshaft sprocket as shown. Pay close attention to their mounting direction.
2. Install the camshaft sprocket and tighten the bolt, to the specified torque.
Tightening torque
Camshaft sprocket bolt 100 - 120 Nm (1000 - 1200 kg.cm, 74 - 89 ft. lbs.)





3. Align the timing marks of the camshaft sprocket and crankshaft sprocket with the No. 1 piston placed at top dead center and its compression stroke.
4. Install the timing belt tensioner and idler pulley.
5. Install the timing belt on the camshaft.
6. Install the timing belt on the crankshaft.
When the timing belt is installed on the camshaft sprocket, make sure that the tension side is tight then tighten the timing belt tensioner pulley pushing toward the coolant pump.
7. Turn the crankshaft one turn in operating direction (clockwise) and realign crankshaft sprocket timing mark.

CAUTION: Do not turn the crankshaft in a counterclockwise direction. The crankshaft should turn smoothly.

Tightening torque
Tensioner pulley installing bolt 43 - 55 Nm (430 - 550 kg.cm, 32 - 41 ft. lbs.)
8. Then recheck the belt tension. The tension side of timing belt is pushed in horizontally with a moderate force [approx. 2 kg (20 N, 5 lb.)], the timing belt cog end is approx. 4 - 6 mm (0.16 - 0.24 inch) away.





9. Install the timing belt cover.
Tightening torque
Timing belt cover bolt 8 - 10 Nm (80 - 100 kg.cm, 6 - 7.4 ft. lbs.)
10. Install the crankshaft pulley. In this case, make sure that the crankshaft sprocket pin fits the small hole in the pulley.
Tightening torque
Crankshaft pulley bolt 170 - 180 Nm (1700 - 1800 kg.cm, 125 - 133 ft. lbs.)
11. Install the coolant pump pulley.





12. Install the drive belt and adjust the belt tension.