Drive Belt: Testing and Inspection
DRIVE BELT (FOR THE GENERATOR, WATER PUMP, POWER STEERING PUMP (CHECK CONDITION)Required Special Tools:
- MB991502: Scan Tool (MUT-II)
- MB991668: Belt Tension Meter Set
CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
1. Connect special tool MB991668 to the scan tool MB991502.
2. Connect scan too MB991502 to the data link connector.
3. Turn the ignition switch to the "ON" and select scan tool MB991502 "Belt Tension Measurement" from the menu screen.
4. Hold special tool MB991668 (microphone) to the middle of the drive belt between the pulleys (at the place indicated by the arrow), about 10 - 20 mm (0.4 - 0.8 inch) away from the rear surface of the belt and so that it is perpendicular to the belt (within an angle off 15 degree angle).
CAUTION:
- The temperature of the surface of the belt should be as close as possible to underhood temperature.
- Do not let any contaminants such as water or oil get onto the microphone.
- If strong gusts of wind blow against the microphone or if there are any loud sources of noise nearby, the values measured by the microphone may not correspond to actual values.
- If the microphone is touching the belt while the measurement is being made, the values measured by the microphone may not correspond to actual values.
- Do not take the measurement while the vehicle's engine is running.
Standard Value:
5. Gently tap the middle of the belt between the pulleys (the place indicated by the arrow) with your finger as shown in the illustration, and check that the vibration frequency of the belt is within the standard value.
Standard Value:
Use a belt tension gauge to check that the belt tension is within the standard value.
Standard Value:
Apply 98 N (22 pound) of force to the middle of the drive belt between the pulleys (at the place indicated by the arrow) and check that the amount of deflection in within the standard value.
GENERATOR DRIVE BELT TENSION ADJUSTMENT
1. Loosen the tensioner pulley fixing nut.
Standard Value:
2. With the tensioner pulley fixing nut temporarily tightened to 15 ± 5 Nm (11 ± 4 ft-lb), set the belt tension or defection amount to the standard value using the adjusting bolt.
3. Tighten the tension pulley fixing nut.
Tightening torque: 49 ± 10 Nm (36 ± 7 ft-lb)
POWER STEERING OIL PUMP DRIVE BELT TENSION CHECK AND ADJUSTMENT
Check the drive belt tension by the following procedure.
Required Special Tools:
- MB991502: Scan Tool (MUT-II)
- MB991668: Belt Tension Meter Set
Gently tap the middle of the belt between the pulleys (the location indicated by the arrow) with your finger as shown in the illustration, and check that the vibration frequency of the belt is within the standard value.
NOTE: Refer to for details on the method of measuring the vibration frequency using the scan tool.
Use a belt tension gauge to check that the belt tension is within the standard value.
Standard Value:
Standard Value:
Apply 98 N (22 pound) of force to the middle of the drive belt between the pulleys (at the place indicated by the arrow) and check that the amount of deflection is within the standard value.
If the tension or deflection is outside the standard value, adjust by the following procedure.
1. Loosen the tension pulley fixing nut and bolt.
2. Adjust the belt tension using the adjusting bolt.
3. Tighten the fixing nut and bolt.
Tightening torque: 44 ± 10 Nm (33 ± 7 ft-lb)
CAUTION: Check after turning the crankshaft one or more rotation clockwise.
4. Check the belt deflection amount and tension, and readjust if necessary.