ALTERNATOR DRIVE BELT AUTO-TENSIONER CHECK



OPERATION CHECK


1.Turn off the engine from the idle state then check to see that the alternator and others belt are not protruding from the pulley width of the alternator drive belt auto-tensioner.
2.Remove the alternator and others belt (Refer to ).

3.Set an offset wrench [recommendation: 45 degrees, a long offset wrench (5/8 x 11/16 inches)] to the pulley bolt of the alternator drive belt auto-tensioner, and check that no binding is present by turning the alternator drive belt auto-tensioner in the left and right directions.
4.If there are any problems in the procedure 1 or 3, replace the alternator drive belt auto-tensioner (Refer to ).
5.Install the alternator and others belt (Refer to ).

FUNCTION CHECK


The alternator drive belt auto-tensioner can be checked whether it is in good condition by checking its tension.

<When the vibration frequency is measured: Recommendation>


note The vibration frequency measuring method is recommended for check and adjustment of the drive belt tension.
1.Check the tension of the alternator and others belt (Refer to ).


2.Check the tension of the alternator and others belt in the following procedures.
(1) Connect special tool microphone assembly (MB992082) to special tool belt tension meter (MB992081) of 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.
note This 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 to normal temperature as possible.
  • Do not allow any contaminants such as water or oil to 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.
Hold special tool (MB992080) to the middle of the alternator and others belt between the pulleys (at the place indicated by arrow) where it does not contact the alternator and others belt (approximately 10 - 15 mm away from the rear surface of the belt) so that it is perpendicular to the alternator and others belt (within an angle of ± 15 degrees).
(6) Press the "MEASURE" button.
(7) Gently tap the middle of the alternator and others 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 alternator and others belt is within the standard value.
Standard value: 102 - 129 Hz
note To take the measurement repeatedly, fillip the alternator and others belt again.
(8) Press and hold the "POWER" button to turn off the power supply.
3.If not within the standard value, replace the alternator drive belt auto-tensioner (Refer to ).

<When tension is measured>


1.Check the tension of the alternator and others belt (Refer to ).

2.Use a belt tension gauge in the middle of the alternator and others belt between the pulleys shown in the figure (at the place indicated by the arrow) to check that the alternator and others belt tension is within the standard value.
Standard value: 248 - 400 N
3.If not within the standard value, replace the alternator drive belt auto-tensioner (Refer to ).