Subaru IMPREZA 2002 Service Manual page 149

MECHANICAL
TIMING BELT ASSEMBLY
C: INSPECTION
1. TIMING BELT
1) Check the timing belt teeth for breaks, cracks,
and wear. If any fault is found, replace the belt.
2) Check the condition of back side of belt; if any
crack is found, replace the belt.
CAUTION:
Be careful not to let oil, grease or coolant
contact the belt. Remove quickly and thorough-
ly if this happens.
Do not bend the belt sharply.
Bending radius: h
60 mm (2.36 in) or more
G2M011 E
2. AUTOMATIC BELT TENSION ADJUST-
ER
1) Visually check the oil seals for leaks, and rod
ends for abnormal wear or scratches. If necessary,
replace the faulty parts.
CAUTION:
Slight traces of oil at rod's oil seal does not in-
dicate a problem.
2) Check that the adjuster rod does not move when
a pressure of 294 N (30 kgf, 66 Ib) is applied to it.
This is to check adjuster rod stiffness.
3) If the adjuster rod is not stiff and moves freely
when applying 294 N (30 kgf, 66 Ib), check it using
the following procedures:
(1) Slowly press the adjuster rod down to the
end surface of the cylinder. Repeat this motion 2
or 3 times.
(2) With the adjuster rod moved all the way up,
apply a pressure of 294 N (30 kgf, 66 Ib) to it.
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 one.
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-in the push adjuster rod gradually tak-
ing more than three minutes.
Do not allow press pressure to exceed 9,807
N (1,000 kgf, 2,205 Ib).
Press the adjuster rod as far as the end sur-
face of the cylinder. Do not press the adjuster
rod into the cylinder. Doing so may damage the
cylinder.
4) Measure the extension of rod beyond the body. If
it is not within specifications, replace with a new
one.
Rod extension: H
5 . 7 - M .
5 mm
( 0 . 2 2 4 - M .
020 in)
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 if faulty.
2) Check the tension pulley for smooth rotation. Re-
place if noise or excessive play is noted.
3) Check the tension pulley for grease leakage.
4. BELTIDLER
1) Check the belt idler for smooth rotation. Replace
if noise or excessive play is noted.
2) Check the belt outer contacting surfaces of idler
pulley for abnormal wear and scratches.
3) Check the belt idler for grease leakage.
ME( SO HC)-51