DRIVE BELT TENSION CHECK AND ADJUSTMENT


M11102000906ENG0000010001



ALTERNATOR DRIVE BELT TENSION CHECK



Check the drive belt tension in the following procedure.
Item
When checked
When adjusted
When replaced
Vibration frequency Hz
150 - 201
164 - 190
190 - 232
Tension N
245 - 441
294 - 392
392 - 588
Deflection mm (Reference)
9.1 - 12.7
9.8 - 11.7
7.2 - 9.8

<When the vibration frequency is measured {Special tool (MB992080) is used}: Recommendation>


noteThe vibration frequency measuring method is recommended for check and adjustment of the drive belt tension.

1. Connect the Special tool microphone assembly (MB992082) to the Special tool belt tension meter (MB992081) of the Special tool belt tension meter set (MB992080).
2. Press the "POWER" button to turn on the power supply.
3. Press number key 1. Check to ensure that "No. 01" appears on the upper left of the display and that the following numeric values are displayed for individual items (M, W, and S):
M 000.9 g/m
W 010.0 mm/R
S 0100 mm
If numeric values have not been entered (new tool), set them according to the belt specifications as shown below. Once you set them, you do not have to set them again. The settings remain undeleted even after battery replacement.
noteThis operation is to temporarily set the preset data such as the belt specifications, because if the measurement is taken without input of the belt specifications, conversion to tension value (N) cannot be made, resulting in judgement of error.
<Setting procedure>
(1)Press down the "MASS" button till the belt mass select display appears.
(2)Press the "UP" or "DOWN" button to select "01 1.5GT 0.9" and press the "MEASURE" button to decide it.
Check to ensure that "M 000.9 g/m" is displayed.
(3)Press the "WIDTH" button to change to the belt width input display.
(4)Press number keys 0, 1, 0, and 0 sequentially, and press the "SELECT" button to apply them. Check to ensure that "W 010.0 mm/R" appears on the display.
(5)Press the "SPAN" button to change to the span length input display.
(6)Press number keys 0, 1, 0, and 0 sequentially, and press the "SELECT" button to apply them. Check to ensure that "S 0100 mm" appears on the display.
4. Press "Hz" button twice to change the display to the frequency display (Hz).

5.
caution
  • The temperature of the surface of the belt should be as close as possible to normal 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 is 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.
Hold the microphone to the middle of the drive belt between the pulleys (at the place indicated by the arrow), about 10 - 15 mm away from the rear surface of the belt and so that it is perpendicular to the belt (within an angle of ± 15 °).
6. Press the "MEASURE" button.
7. 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.
noteTo take the measurement repeatedly, fillip the belt again.
8. After the completion of the measurement, press and hold the "POWER" button to turn off the power supply.

<When using the tension gauge>



Use a belt tension gauge to check that the belt tension is within the standard value.


<Belt deflection check>



Apply approximately 100 N 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 not within the standard value, adjust the belt tension by the following procedure.
1. Loosen the nut of the alternator pivot bolt.
2. Loosen the alternator fixing bolt.
3. Use the adjusting bolt to adjust the belt tension and belt deflection to the standard values.
4. Tighten the nut for alternator pivot bolt.
Tightening torque: 47 ± 9 N·m
5. Tighten the alternator fixing bolt.
Tightening torque: 24 ± 4 N·m
6. Tighten the adjusting bolt.
Tightening torque: 5.0 ± 1.0 N·m
7.
cautionWhen checking the belt tension, turn the crankshaft clockwise one turn or more.
Check the belt tension, and readjust if necessary.
8. When the belt tension is adjusted by measuring the deflection, adjust it with a tool for vibration frequency measurement or tension measurement afterward.
cautionAlways replace the two V-belts together as a set, and do not apply any oil to the belts.

A/C COMPRESSOR DRIVE BELT TENSION CHECK




Check the drive belt tension by the following procedures.
Standard value:
Vibration frequency Hz
173.2 - 195.2
Tension N
337 - 428
Deflection mm (Reference)
6.5 - 7.6

When the vibration frequency is measured {Special tool (MB992080) is used}: Recommendation


noteThe vibration frequency measuring method is recommended for check and adjustment of the drive belt tension.
With your finger tip lightly tap the center of the drive belt between the pulleys in the location shown by the arrow in the illustration and then measure the belt vibration frequency.
noteRefer to alternator drive belt tension check, for information regarding the vibration frequency measurement method using the special tool (MB992080.)

When using the tension gauge


Use a belt tension gauge to check that the belt tension is within the standard value at the center of the drive belt between the pulleys in the location shown by the arrow in the illustration.

Belt deflection check


Apply approx. 100 N of force to the middle of the center of the drive belt between the pulleys in the location shown by the arrow in the illustration and check that the amount of deflection is within the standard value.
When the belt tension is adjusted by measuring the belt deflection, adjust it with a tool for vibration frequency measurement or tension measurement afterward.