Timing Belt: Service and Repair

TIMING BELT

REMOVAL AND INSTALLATION

Pre-removal and Post-installation Operation:

Removal Steps 1-11:

Removal Steps 12-13:

Required Special Tools:
^ MB990767: End Yoke Holder
^ MD998716: Crankshaft Wrench
^ MD998719: Pin

REMOVAL SERVICE POINTS

[[A]] DRIVE BELT AUTO-TENSIONER/GENERATOR DRIVE BELT REMOVAL

CAUTION: When the generator drive belt is reused, draw an arrow indicating the rotating direction on the back of the belt using chalk to install the same direction.





1. Turn the drive belt auto-tensioner to counterclockwise, and insert the L-shaped hexagon wrench to the auto-tensioner hole in order to fix the auto-tensioner.
2. Remove the generator drive belt.
3. Remove the drive belt auto-tensioner.

[[B]] CRANKSHAFT PULLEY REMOVAL

CAUTION: Use only the specified special tools, or a damaged pulley damper could result.





Use special tools MB990767 and MD998719 to remove the crankshaft pulley from the crankshaft.

[[C]] TIMING BELT AUTO-TENSIONER REMOVAL





1. Remove the upper tightening bolt of the auto-tensioner.

CAUTION: The auto-tensioner rotates centering on the flange bolt due to the rod thrust, so please make sure your finger is not trapped.

2. Loosen the lower tightening bolt of the auto-tensioner slowly and slide the auto-tensioner slightly. Remove the rod from the tensioner arm.
3. Remove the lower tightening bolt of the auto-tensioner.

[[D]] TIMING BELT REMOVAL

CAUTION: Never turn the crankshaft counterclockwise.





1. Turn the crankshaft clockwise to align each timing mark and to set the number 1 cylinder to compression top dead center.
2. If the timing belt is to be reused, chalk an arrow on the flat side of the belt, indicating the clockwise direction.
3. Loosen the center bolt of the tensioner pulley, then remove the timing belt.

INSTALLATION SERVICE POINTS

]]A[[ TIMING BELT/TIMING BELT AUTO-TENSIONER INSTALLATION

CAUTION: Always bleed the auto-tensioner of air before installing the auto-tensioner.

Insert the pin into the rod of the auto-tensioner under the following procedures.





CAUTION: Notable factors for inserting pin
^ Always use the vertical press and put the auto-tensioner vertically.
^ Do not apply the load of 5,000 N (1,124 pound) or more to the rod.
^ Do not press the rod beyond the dimension shown in the illustration.

1. Put the auto-tensioner vertically to the vertical press not to be in the sideways direction.





2. Slowly close the vice to force the rod in until the hole (A) of the rod is lined up with set hole (B) of the cylinder.
3. Insert a pin into the set holes.
4. Remove the auto-tensioner from the vice.








5. Align the timing marks on the camshaft sprockets with those on the timing belt rear cover and the timing mark on the crankshaft sprocket with that on the engine block as shown in the illustration.

CAUTION: The camshaft sprocket (right bank) can turn easily due to the spring force applied, so be careful not to get your fingers caught.





6. Install the timing belt by the following procedure so that there is no deflection in the timing belt between each sprocket and pulley.
1) Crankshaft sprocket
2) Water pump pulley
3) Camshaft sprocket (Left bank)
4) Idler pulley
5) Camshaft sprocket (Right bank)
6) Tensioner pulley
7. Turn the camshaft sprocket (Right bank) counterclockwise until the tension side of the timing belt is firmly stretched. Check all the timing marks again.





8. Use special tool MD998716 to turn the crankshaft 1/4 turn counterclockwise, then turn it again clockwise until the timing marks are aligned.
9. Remove the setting pin that has been inserted into the auto-tensioner.
10. Turn the crankshaft clockwise twice to align the timing marks.





11. Wait for at least five minutes, then check that the auto-tensioner pushrod extends within the standard value range.

Standard value (A): 9.1 - 13.4 mm (0.36 - 0.52 inch)

12. If not, repeat the operation in steps 1 to 6 above.
13. Check again that the timing marks of the sprockets are aligned.

]]B[[ CRANKSHAFT PULLEY INSTALLATION





Use special tools MB990767 and MD998719 to install the crankshaft pulley.

INSPECTION

TIMING BELT AUTO-TENSIONER CHECK
1. Check for oil leak from seal, and replace it if leak is detected.
2. Check for wear or damage at the top of the rod. Replace it, if required.

AIR BLEEDING METHOD

CAUTION:
^ Always use the vertical press and put the auto-tensioner vertically.
^ Do not apply the load of 5,000 N (1,124 pound) or more to the rod.
^ Do not press the rod beyond Dimension "A" shown in the illustration.





1. Set the auto-tensioner as shown in the illustration.
2. Press the rod slowly down to the lowest point "A" shown in the illustration.
3. Repeat the procedure 2 three times.
4. While the rod is projected at the point "B" shown in the illustration, push the rod with 100 - 200 N (22 - 44 pound). Check the enough stiffness. If the stiffness is not enough, replace the auto-tensioner.
5. Press down the rod slowly. Put the pin through the hole and secure it.