Service Manual

Belt Tensioner, Refrigerant Compressor, Automatic ISB, ISBe and QSB (Common Rail [...]
Page 9-28 Section 9 - Drive Units - Group 09
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Remove
Remove the capscrew and belt tensioner from the
mounting location.
Install
With the belt removed, verify the tensioner arm stop is in
contact with the spring casing stop.
If these two are not touching, the tensioner must be
replaced.
Measure the clearance between the tensioner spring
casing and the tensioner arm to verify tensioner wear-out
and uneven bearing wear.
If the clearance exceeds 3 mm [0.12 in] at any point, the
tensioner must be replaced as a complete assembly.
Tensioners usually show a larger clearance gap near the
lower portion of the spring casing, resulting in the upper
portion rubbing against the tensioner arm. Always replace
the belt when a tensioner is replaced.
1. Tensioner cap
2. Tensioner arm
3. Spring case
4. Tensioner pulley
5. Clearance gap.
Inspect the tensioner for evidence of the tensioner arm
contacting the tensioner cap.
If there is evidence of the two areas making contact, the
pivot tube bushing has failed and the tensioner must be
replaced.