Drive Belt: Service and Repair

WM 137819 Removing and installing drive belt on V6 DFI engines

Preliminary work

1. Remove front engine compartment cover. For details, see => 700219 Removing and installing front trim (engine compartment) - section on "Removing"
2. Remove intake manifold between the air cleaner and throttle housing. For details, see => 243519 Removing and installing air box for throttle housing on DFI engines (intake pipes upstream of throttle valve) - section on "Removing"

Removing and installing drive belt

CAUTION

Risk of damage.

- If the drive belt is removed when it is hot, it may become deformed and damaged.

-> Never remove the drive belt when it is hot - let the engine cool down.

CAUTION

Drive belt breaks and becomes jammed

- Risk of damage to components (trim panels, electric cables, etc.)
- Sealing ring on crankshaft vibration balancer can start to leak
- Vibration balancer can overheat and lose its strength

-> Following belt breakage, check adjacent components and the interior of the engine compartment for damage, and repair or replace damaged parts if necessary.
-> Find out why the belt broke. Check deflection rollers or crankshaft vibration balancer for prior damage.
-> If the drive belt is jammed, replace vibration balancer.

Information

- If the drive belt is to be re-used, mark the rolling direction with chalk so that the belt can be re-installed later in the same rolling direction.

1. Mark the rolling direction of the drive belt with chalk. -arrow-





Rolling direction of drive belt

2. Slacken the belt tensioner. To do this, screw an M8 x 50 screw into the belt tensioner. Do not turn the belt tensioner as far as it will go; only slacken the tensioner until the drive belt is loose and easily accessible. -arrow-





Loosening the belt tensioner

3. Remove the drive belt from all pulleys.





Drive belt threading course





4. Place drive belt around the vibration balancer and loop in direction of travel going left. => Vibration damper





Vibration damper

5. Guide the top end of the belt around the coolant pump. Then, position the belt vertically (turn by 90°) and guide it in behind the belt tensioner. => Belt threading course at coolant pump





Belt threading course at coolant pump

6. Guide the lower end of the belt from the vibration balancer around the air-conditioning compressor and then around the hydraulic pump (power-steering pump/tandem pump). Push the belt upwards from there. => Belt threading course at air-conditioning compressor





Belt threading course at air-conditioning compressor

7. Guide the drive belt over the drive roller of the generator and then pull a loop down around the deflection roller and lay into position. => Belt threading course at generator





Belt threading course at generator

8. Check that the drive belt is positioned correctly and is placed correctly on the rollers.
9. Tighten the belt tensioner. To do this, remove the M8 x 50 screw on the belt tensioner. -arrow-





Belt tensioner

Subsequent work

1. Fit intake manifold between the air cleaner and throttle housing. For details, see => 243519 Removing and installing air box for throttle housing on DFI engines (intake pipes upstream of throttle valve) - section on "Installing"
2. Fit front engine compartment cover. For details, see => 700219 Removing and installing front trim (engine compartment) - section on "Installing"