Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual - part 172

ME(w/o STI)-69

Cylinder Head

MECHANICAL

(4) Retighten  all  bolts  to  95  N·m  (9.7  kgf-m,

70.1 ft-lb) in alphabetical order.

CAUTION:

If the bolt makes stick-slip sound during tight-

ening,  repeat  the  procedure  from  step  (1).  In

this case, the cylinder head gasket can be re-

used.

(5) Loosen all the bolts by 180° in the reverse

order of installing, and loosen them further by

180°.

(6) Tighten all bolts to 10 N·m (1.0 kgf-m, 7.4 ft-lb)

in alphabetical order.

(7) Retighten  all  bolts  to  30  N·m  (3.1  kgf-m,

22.1 ft-lb) in alphabetical order.

(8) Retighten  all  bolts  to  70  N·m  (7.1  kgf-m,

51.6 ft-lb) in alphabetical order.

(9) Retighten all bolts by 80 — 90° in alphabet-

ical order.

(10) Retighten all bolts by 40 — 45° in alphabet-

ical order.

CAUTION:

The tightening angle of the bolt should not ex-

ceed 45°.

(11) Retighten bolts (A) and (B) by 40 — 45°.

CAUTION:

Make sure the total “tightening angle” of steps

(10) and (11) does not exceed 90°.

2) Install the oil level gauge guide. (LH side only)
Tightening torque:

6.4 N·m (0.7 kgf-m, 4.7 ft-lb)

3) Install  the  camshaft.  <Ref.  to  ME(w/o  STI)-61,

INSTALLATION, Camshaft.>

4) Install the oil pipe. <Ref. to LU(STI)-27, INSTAL-

LATION, Oil Pipe.>

5) Install  the  A/C  compressor  bracket  on  cylinder

head.
Tightening torque:

36 N·m (3.7 kgf-m, 26.6 ft-lb)

6) Install  the  secondary  air  combination  valve.

<Ref. to EC(w/o STI)-31, INSTALLATION, Second-

ary Air Combination Valve.>

7) Install the cam sprocket. <Ref. to ME(w/o STI)-

57, INSTALLATION, Cam Sprocket.>

8) Install the timing belt. <Ref. to ME(w/o STI)-50,

INSTALLATION, Timing Belt.>

9) Adjust  the  valve  clearance.  <Ref.  to  ME(w/o

STI)-28, ADJUSTMENT, Valve Clearance.>

10) Install the rocker cover.

(1) Install the rocker cover gasket to the rocker

cover. (outer section and ignition coil section)

NOTE:

Use a new rocker cover gasket.

(2) Apply liquid gasket to the specified point of

the cylinder head.

NOTE:

Install within 5 min. after applying liquid gasket.
Liquid gasket:

THREE BOND 1217G (Part No. K0877Y0100) 

or equivalent

(3) Install the rocker cover onto cylinder heads.

Ensure the gasket is properly positioned during

installation.

ME-05984

(F)

(A)

(C)

(D)

(B)

(E)

(C)

(A)

(F)

(E)

(B)

(D)

ME-05981

ME(w/o STI)-70

Cylinder Head

MECHANICAL

(4) Temporarily tighten the rocker cover bolts in

alphabetical order shown in the figure, and then

tighten to specified torque in alphabetical order.

Tightening torque:

6.4 N·m (0.7 kgf-m, 4.7 ft-lb)

11) Connect the PCV hose (A) and PCV hose as-

sembly (B) to the rocker cover.
NOTE:

Use a new clamp for the PCV hose (A), fit the cut

out in the ST with the protrusion on the clamp as

shown in the figure, and lock the clamp.

ST 18353AA000 CLAMP PLIERS

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.>

14) Install  the  intake  manifold.  <Ref.  to  FU(w/o

STI)-22, INSTALLATION, Intake Manifold.>

15) Install the rear side belt. <Ref. to ME(w/o STI)-

39, REAR SIDE BELT, INSTALLATION, V-belt.>

16) Install the engine to the vehicle. <Ref. to ME(w/

o STI)-33, INSTALLATION, Engine Assembly.>

ME-05982

(E)

(F)

(H)

(G)

(D),(L)

(A),(I)

(C),(K)

(B),(J)

(B),(J)

(H)

(F)

(C),(K)

(E)

(A),(I)

(D),(L)

(G)

ME-04374

ST

ME-05768

(A)

(B)

(A)

(B)

ME(w/o STI)-71

Cylinder Head

MECHANICAL

C: DISASSEMBLY

1) Remove the valve lifter.

2) Place the cylinder head on ST1.

ST1 498267600

CYLINDER HEAD TABLE

3) Using  ST2,  compress  the  valve  spring  and  re-

move the valve spring retainer key. Remove each

valve and valve spring.

ST2 499718000

VALVE SPRING REMOVER

NOTE:

• Mark each valve to prevent confusion.

• Pay careful attention not to damage the lips of in-

take valve oil seals and exhaust valve oil seals.

• Keep all the removed parts in order for re-install-

ing in their original positions.

• For  removal  and  installation  procedures  of  the

valve guide, intake valve oil seal and exhaust valve

oil seal, refer to “INSPECTION”. <Ref. to ME(w/o

STI)-73,  VALVE  GUIDE,  INSPECTION,  Cylinder

Head.>  <Ref.  to  ME(w/o  STI)-76,  INTAKE  AND

EXHAUST VALVE OIL SEAL, INSPECTION, Cyl-

inder Head.>

ME-05003

ST1

ST2

ME(w/o STI)-72

Cylinder Head

MECHANICAL

D: ASSEMBLY

1) Install the valve spring and valve.

(1) Coat the valve stem of each valve with en-

gine oil and insert the valve into valve guide.

NOTE:

When inserting the valve into valve guide, use spe-

cial care not to damage the oil seal lip.

(2) Set the cylinder head on ST1.

ST1 498267600

CYLINDER HEAD TABLE

(3) Install the valve spring and valve spring re-

tainer.

NOTE:

Be  sure  to  install  the  valve  spring  with  its  close-

coiled end facing the cylinder head side.

(1)

Exhaust valve

(5)

Intake valve oil seal

(9)

Valve lifter

(2)

Intake valve

(6)

Valve spring

(10) Exhaust valve oil seal

(3)

Cylinder head

(7)

Valve spring retainer

(11) Intake valve guide

(4)

Valve spring seat

(8)

Valve spring retainer key

(12) Exhaust valve guide

(3)

(1)

(12)

(10)

(4)

(6)

(7)

(8)

(9)

(10)

(4)

(6)

(7)

(8)

(9)

ME-04990

(12)

(2)

(11)

(4) (5)

(6)

(7) (8)

(9)

(11)

(4) (5)

(6)

(7) (8) (9)