Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 168

ME(w/o STI)-53

Timing Belt

MECHANICAL

8) Align the alignment mark on the timing belt with marks on the sprockets in the alphabetical order shown

in the figure. While aligning marks, position the timing belt properly, and install the timing belt.
CAUTION:

• If the timing belt slips by 1 or more teeth, the valve and piston may hit each other.

• Make sure that the direction of belt rotation is correct.

9) Install the belt idlers.
Tightening torque:

39 N·m (4.0 kgf-m, 28.8 ft-lb)

NOTE:

Make sure that the marks on the timing belt and

sprockets are aligned.

10) After ensuring that the marks on the timing belt

and sprockets are aligned, remove the stopper pin

from tensioner adjuster.

(1)

Arrow mark

(4)

54.5 teeth

(6)

28 teeth

(2)

Timing belt

(5)

51 teeth

(7)

Install it in the end

(3)

28 teeth

ME-04718

(1)

(2)

(5)

(6)

(4)

(D)

(A)

(C)

(B)

(E)

(3)

RH-IN

RH-EX

LH-EX

LH-IN

(7)

ME-04982

ME-00245

ME(w/o STI)-54

Timing Belt

MECHANICAL

11) Install the timing belt guide.

(1) Temporarily tighten the bolts securing the

timing belt guide.

NOTE:

• Before installing the timing belt guide, clean the

timing belt guide mounting bolt holes of the timing

belt cover No. 2.

• Apply liquid gasket to the thread of the timing belt

guide mounting bolt on the cam sprocket section.

(when reusing bolts)
Liquid gasket:

THREE BOND 1324 (Part No. 004403042)

(2) Adjust the clearance between timing belt

and timing belt guide using a thickness gauge

and tighten.

Clearance:

1.0

±

0.5 mm (0.039

±

0.020 in)

ME-00230

ME-03124

ME-00728

ME-00729

ME-00246

ME-03138

ME-00731

ME-00732

ME(w/o STI)-55

Timing Belt

MECHANICAL

Tightening torque:

9.75 N·m (1.0 kgf-m, 7.2 ft-lb)

Tightening torque:

6.4 N·m (0.7 kgf-m, 4.7 ft-lb)

12) Install the timing belt cover. <Ref. to ME(w/o

STI)-47, INSTALLATION, Timing Belt Cover.>

13) Install the crank pulley. <Ref. to ME(w/o STI)-

45, INSTALLATION, Crank Pulley.>

C: INSPECTION

1. TIMING BELT

1) Check the timing belt teeth for breaks, cracks or

wear. If any fault is found, replace the timing belt.

2) Check the condition on the back surface of the

timing belt. If cracks are found, replace the timing

belt.
CAUTION:

• Be careful not to let oil, grease or coolant

contact the timing belt. Remove quickly and

thoroughly if this happens.

• Do not bend the timing belt sharply.
In radial diameter h:

60 mm (2.36 in) or more

ME-00247

ME-03124

ME-00728

ME-00729

ME-00248

h

ME(w/o STI)-56

Timing Belt

MECHANICAL

2. AUTOMATIC BELT TENSION ADJUST-

ER

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 the rod oil seal does not indi-

cate 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-in the push adjuster rod gradually tak-

ing 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 adjuster rod protrusion

“L” from the end surface of the cylinder. If it is not

within specifications, replace the automatic belt

tension adjuster assembly with a new part.
Protrusion amount of adjuster rod L:

5.2 — 6.2 mm (0.205 — 0.244 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 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-04106

L