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Timing Belt: Inspection

  1. INSPECT TIMING BELT 
    NOTE:
    • Do not bend, twist or turn the timing belt inside out. Do not allow the timing belt to come into contact with oil, water or steam.
    • Do not utilize timing belt tension when installing or removing the mount bolt of the camshaft timing pulley.

    If there are any defects, as shown in the illustrations, check the following points.

    Fig 1: Do Not Allow Timing Belt To Come Into Contact With Oil, Water Or Steam
    G02948749Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Premature parting
      • Check for proper installation.
      • Check the timing cover gasket for damage and proper installation.
    2. If the belt teeth are cracked or damaged, check to see if either camshaft is locked.
    3. If there is noticeable wear or cracks on the belt face, check to see if there are nicks on the side of the idler pulley lock.
    4. If there is wear or damage on only one side of the belt, check the belt guide and the alignment of each pulley.
    5. If there is noticeable wear on the belt teeth, check timing cover for damage and check gasket has been installed correctly and for foreign material on the pulley teeth.

    If necessary, replace the timing belt.

  2. INSPECT DRIVE BELT TENSIONER 

    Check the turning smoothness of the tensioner.

    If necessary, replace the tensioner.

  3. INSPECT IDLER PULLEY 
    1. Visually check the seal portion of the idler pulley for oil leakage.

      If leakage is found, replace the idler pulley.

    2. Check the turning smoothness of the idler pulley.
    3. Fig 2: Checking Turning Smoothness Of Idler Pulley
      G02948750Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If necessary, replace the idler pulley.

  4. INSPECT TIMING BELT TENSIONER 
    1. Visually check tensioner for oil leakage.

      HINT:

      If there is only the faintest trace of oil on the seal on the push rod side, the tensioner is all right.

      If leakage is found, replace tensioner.

      Fig 3: Checking Tensioner For Oil Leakage
      G02948751Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Hold the tensioner with both hands and push the push rod strongly against the floor or wall to check that it doesn't move.

      If the push rod moves, replace the tensioner.

      Fig 4: Holding Tensioner With Both Hands And Pushing Push Rod Strongly Against Floor Or Wall To Check It Doesn't Move
      G02948752Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the protrusion of the push rod from the housing end.

      Protrusion: 8.0-8.8 mm (0.315-0.346 in.) 

      Fig 5: Measuring Protrusion Of Push Rod From Housing End
      G02948753Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If the protrusion is not as specified, replace the tensioner.

  5. M/T: 

    INSPECT DRIVE BELT TENSIONER ABSORBER 

    Compress and extend the absorber rod and check that there is no abnormal resistance or unusual operation sounds.

    If there is any abnormality, replace the absorber.

    Fig 6: Checking Drive Belt Tensioner Absorber
    G02948754Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    NOTE: When discarding the absorber, use the these procedure.
    • Fully extend the absorber rod. 
    • Using a drill, make a hole in the cylinder as shown to release the gas inside. 
    CAUTION: The gas coming out is harmless, but the careful of the chips which may fly up when drilling.
    Fig 7: Identifying Location For Drilling Hole
    G02948755Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002