Timing Belt

REMOVAL AND INSTALLATION

REMOVAL SERVICE POINTS
[A] TIMING BELT REMOVAL





1. Mark the belt running direction for reference in reinstallation.

NOTE: Water or oil on the belt shortens its life drastically, so the removed timing belt, sprocket, and tensioner must be kept free from oil and water. Do not immerse parts in cleaning solvent.

NOTE: If there is oil or water on any part, check the front case oil seal, camshaft oil seal and water pump for leaks.





[B] CAMSHAFT SPROCKET BOLT LOOSENING

INSTALLATION SERVICE POINTS





]A[ CAMSHAFT SPROCKET BOLT TIGHTENING

]B[ AUTO-TENSIONER INSTALLATION





If the auto-tensioner rod is fully extended, set it in the retracted position with the following procedure.
1. Set the auto-tensioner in a vice.





2. Slowly close the vice to force the rod in until the set hole (A) of the rod is lined up with the set hole (B) of the cylinder.
3. Insert a wire [1.4 mm (0.055 inch) in diameter] into the set holes.
4. Remove the auto-tensioner from the vice.
5. Install the auto-tensioner to the engine.

CAUTION: Do not remove the setting wire from the auto-tensioner.

]C[ TIMING BELT INSTALLATION





1. Move the timing mark of the crankshaft sprocket three teeth counter-clockwise to slightly lower the piston below the top dead center on the compression stroke of the No. 1 cylinder.

CAUTION: If the camshaft sprocket is rotated with the piston at the top dead center on the compression stroke of the No. 1 cylinder, the valve and piston might interfere.





2. Line up the timing marks of the left bank camshaft sprockets.
3. Line up the timing marks of the right bank camshaft sprockets.

CAUTION: Since the camshaft sprocket readily turns because of spring action, use care to make sure that your finger is not caught.





4. Line up the timing marks of the crankshaft sprocket.
5. Install the timing belt on each sprocket in the following sequence.
1. Install the timing belt on the crankshaft sprocket and then on the idler pulley, while tightening it to prevent slackness.
2. Install the timing belt on the left bank camshaft sprocket.
3. Install the timing belt on the water pump pulley, while taking up the slack.
4. Install the timing belt on the right bank camshaft sprocket.
5. Install the timing belt on the tensioner pulley.





6. Lightly press the tensioner pulley against the belt and temporarily tighten the center bolt.
7. Check to see that the timing marks of all the sprockets are in alignment.








8. Using special tool to rotate the crankshaft a quarter of a turn counter-clockwise. Then rotate it back clockwise to verify that all the timing marks are in alignment.





9. Loosen the center bolt of the tensioner pulley. Use the special tool and torque wrench to apply the standard tensioning torque to the timing belt. Tighten the center bolt to the specified torque.
Standard value: 4.4 Nm (3.3 ft. lbs.)

CAUTION: When tightening the center bolt, ensure that the tensioner pulley does not turn with the bolt.

10. Remove the setting wire from the auto-tensioner.
11. Rotate the crankshaft two turns clockwise and let it stand for approximately 5 minutes.





12 Check that the auto-tensioner pushrod profusion is within the range of the standard value.
Standard value (A): 4.8 - 6.0 mm (0.189 - 0.236 inch)
13. If the profusion is out of specification, repeat steps (8) to (11).
14. Check again that the timing marks on all sprockets are aligned.

]D[ ENGINE SUPPORT BRACKET





1. Tighten bolts to specified torque in the sequence shown.

INSPECTION
TIMING BELT
Replace belt if any of the following conditions exist.





1. Hardening of back rubber-back side is glossy without resilience and leaves no indent when pressed with fingernail.





2. Cracks on rubber back
3. Cracks or peeling of canvas
4. Cracks on tooth bottom
5. Cracks on side of belt





6. Abnormal wear of belt sides. The sides are normal if they are sharp as if cut by a knife.





7. Abnormal wear on teeth
8. Tooth missing and canvas fiber exposed.

TENSIONER





1. Turn the pulley. If it does not rotate smoothly, develops noise or excessive play, replace the timing belt tensioner.

AUTO-TENSIONER





1. Check for oil leaks. If oil leaks are evident, replace the auto-tensioner.
2. Check the rod end for wear or damage and replace the auto-tensioner if necessary.
3. Measure the rod projection length. If the reading is outside the standard value, replace the auto-tensioner.
Standard value: 11.7 - 12.3 mm (0.461 - 0.484 inch)





4. Press the rod with a force of 98 to 196 N (22 to 44 lbs.) and measure the movement of rod.
If the measured value is more than the standard value, replace the auto-tensioner.
Standard value: 1 mm (0.0393 inch) or less.