Subaru 2009 IMPREZA Service Manual page 271

2. AUTOMATIC BELT TENSION ADJUSTER
1) Visually check the oil seals for leaks, and rod
ends for abnormal wear and scratches. If neces-
sary, replace the automatic belt tension adjuster
assembly.
NOTE:
Slight traces of oil at rod's oil seal does not indicate
a problem.
2) Check that the adjuster rod does not move when
a pressure of 165 N (16.8 kgf, 37.1 lb) is applied to
it. This is to check adjuster rod stiffness.
3) If the adjuster rod is not stiff and moves freely
when applying 165 N (16.8 kgf, 37.1 lb), check it us-
ing the following procedures:
(1) Slowly press the adjuster rod down to the
end surface of cylinder. Repeat this operation
two to three times.
(2) With the adjuster rod moved all the way up,
apply a pressure of 165 N (16.8 kgf, 37.1 lb) to
it, and check the adjuster rod stiffness.
(3) If the adjuster rod is not stiff and moves
down, replace the automatic belt tension adjust-
er assembly with a new part.
CAUTION:
• Always use a vertical type pressing tool to
move the adjuster rod down.
• Do not use a lateral type vise.
• Push the adjuster rod vertically.
• Press the adjuster rod gradually taking three
minutes or more.
• Do not allow press pressure to exceed 9,807 N
(1,000 kgf, 2,205 lb).
• Push in the adjuster rod to the end face of the
cylinder. However, do not press the adjuster
rod below the end face of the cylinder. Doing so
may damage the cylinder.
4) Measure the amount of rod protrusion "H" from
the end surface of the body. If it is not within spec-
ifications, replace the automatic belt tension adjust-
er assembly with a new part.
Amount of rod protrusion H:
5.2 — 6.2 mm (0.204 — 0.244 in)
H
Timing Belt
3. BELT TENSION PULLEY
1) Check the mating surfaces of timing belt and
contact point of adjuster rod for abnormal wear or
scratches. Replace the automatic belt tension ad-
juster assembly with a new part if faulty.
2) Check the belt tension pulley for smooth rota-
tion. Replace the automatic belt tension adjuster
assembly with a new part if abnormal noise or ex-
cessive play occurs.
3) Check the belt tension pulley for grease leakage.
4. BELT IDLER
1) Check the belt idler for smooth rotation. Replace
if noise or excessive play occurs.
2) Check the outer contacting surfaces of idler pul-
ley for abnormal wear and scratches.
3) Check the belt idler for grease leakage.
ME-00249
ME(H4SO)-53
MECHANICAL