Mitsubishi Galant 9G. Manual - part 591

CYLINDER HEAD AND VALVES

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ENGINE OVERHAUL <2.4L ENGINE>

11B-36

>>B<< VALVE SPRING INSTALLATION

Install the valve spring with its identification color painted end
(larger pitch side) upward (toward the valve spring retainer).

Identification:

<Intake> Light blue
<Exhaust> Orange

>>C<< RETAINER LOCK INSTALLATION

CAUTION

Do not compress the valve spring excessively. It can dam-
age the stem seal.
1. Set special tool MD998735 as illustrated to compress the

valve spring. Install the retainer locks.

2. Relieve the spring tension. Check that the retainer locks are

seated correctly.

>>D<< CYLINDER HEAD BOLT INSTALLATION

1. When the removed cylinder head bolts are to be reused,

check that the shank length of each bolt meets the limit. If it
exceeds the limit, replace the bolts.

Limit: 99.4 mm (3.91 inches)

2. Apply engine oil to the thread of the bolts and to the

washers.

AK300717

PAINTED END

AK300163

MD998735

AK300591AE

SHANK LENGTH

CYLINDER HEAD AND VALVES

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ENGINE OVERHAUL <2.4L ENGINE>

11B-37

3. Using special tool MB991654 tighten the bolts to the

specified torque, using the tightening sequence shown.

Tightening torque: 78

± 2 N⋅m (58 ± 2 ft-lb)

4. Loosen all bolts fully in the reverse order of tightening.
5. Retighten the loosened bolts to the specified torque in the

tightening sequence shown.

Tightening torque: 20

± 2 N⋅m (15 ± 1 ft-lb)

6. Make a paint mark across each bolt head and cylinder head.
7. Tighten the cylinder head bolts 90 degrees in the specified

order.

CAUTION

• If the bolt is turned less than 90 degrees, proper fasten-

ing performance may not be achieved. Be careful to
turn each bolt exactly 90 degrees.

• If the bolt is overtightened, loosen the bolt completely

and then retighten it by repeating the tightening proce-
dure from step 1.

8. Tighten the bolts another 90 degrees in the same order as in

step 7, and check that the paint marks on the cylinder head
bolt are aligned with the paint marks on the cylinder head.

INSPECTION

M1113007000431

CYLINDER HEAD

1. Check the cylinder head gasket surface for flatness by using

a straight edge and feeler gauge.

Standard value: 0.03 mm (0.001 inch)
Limit: 0.2 mm (0.007 inch)

2. If it exceeds the limit, correct to meet specification.

Grinding limit: *0.2 mm (0.007 inch)

* Includes combined with cylinder block grinding.

Cylinder head height (Specification when new):
120 mm (4.7 inches)

AK300165

MB991654

AK301394AC

TIMING BELT SIDE

AK300166

90˚

PAINT MARK

AK300167

CYLINDER HEAD AND VALVES

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ENGINE OVERHAUL <2.4L ENGINE>

11B-38

VALVE

1. Check the valve seat contact. Valve seat contact should be

uniform at the center of the valve face. If incorrect, reface
using a valve refacer.

2. If the margin is below the limit, replace the valve.

Standard value:

<Intake> 1.0 mm (0.03 inch)
<Exhaust> 1.2 mm (0.04 inch)

Minimum limit:

<Intake> 0.5 mm (0.02 inch)
<Exhaust> 1.0 mm (0.03 inch)

3. Measure the valve's total length. If the measurement is less

than the limit, replace the valve.

Standard value:

<Intake> 111.33 mm (4.383 inches)
<Exhaust> 113.54 mm (4.470 inches)

Minimum limit:

<Intake> 110.83 mm (4.363 inches)
<Exhaust> 113.04 mm (4.450 inches)

VALVE SPRING

1. Measure the free height of the spring. If it is less than the

limit, replace.

Standard value:

<Intake> 54.8 mm (2.16 inches)
<Exhaust> 56.1 mm (2.21 inches)

Minimum limit:

<Intake> 53.8 mm (2.12 inches)
<Exhaust> 55.1 mm (2.17 inches)

2. Measure the squareness of the spring. If it exceeds the limit,

replace.

Standard value: 2 degrees or less
Limit: 4 degrees

VALVE GUIDE

Measure the clearance between the valve guide and valve
stem. If it exceeds the limit, replace the valve guide or valve, or
both.

Standard value:

<Intake> 0.02

− 0.04 mm (0.0008 − 0.0016 inch)

<Exhaust> 0.04

− 0.06 mm (0.0016 − 0.0024 inch)

Limit:

<Intake> 0.10 mm (0.003 inch)
<Exhaust> 0.15 mm (0.005 inch)

AK300593AD

MARGIN

CONTACT
(SHOULD BE AT
CENTER OF FACE)

AK103808AD

TOTAL LENGTH

AK300718AD

OUT OF SQUARE

FREE HEIGHT

AK300168

GUIDE INSIDE DIAMETER

STEM DIAMETER

VALVE
GUIDE

CYLINDER HEAD AND VALVES

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ENGINE OVERHAUL <2.4L ENGINE>

11B-39

VALVE SEAT

Assemble the valve, then measure the valve stem projection
between the end of the valve stem and the spring seating sur-
face. If the measurement exceeds the specified limit, replace
the valve seat.

Standard value:

<Intake> 48.33 mm (1.902 inches)
<Exhaust> 48.34 mm (1.903 inches)

Limit:

<Intake> 48.83 mm (1.922 inches)
<Exhaust> 48.84 mm (1.923 inches)

VALVE SEAT RECONDITIONING PROCEDURE

1. Before correcting the valve seat, check for clearance

between the valve guide and valve and, if necessary,
replace the valve guide.

2. Using the seat grinder, correct to obtain the specified seat

width and angle.

3. After correcting the valve seat, lap the valve and valve seat

using lapping compound. Then, check the valve stem
projection.

VALVE SEAT REPLACEMENT PROCEDURE

1. Cut the valve seat from the inside to thin the wall thickness.

Then, remove the valve seat.

2. Rebore the valve seat hole in the cylinder head to a selected

oversize valve seat diameter.

Intake seat ring hole diameters

0.3 oversize:

35.30

− 35.33 mm (1.3898 − 1.3909 inches)

0.6 oversize:

35.60

− 35.63 mm (1.4016 − 1.4028 inches)

Exhaust seat ring hole diameters

0.3 oversize:

33.30

− 33.33 mm (1.3110 − 1.3122 inches)

0.6 oversize:

33.60

− 33.63 mm (1.3228 − 1.3240 inches)

AK300596

VALVE STEM
PROJECTION

SPRING
SEATING
SURFACE

VALVE STEM
END

AK300385AD

INTAKE SIDE

EXHAUST SIDE

43.5˚ – 44˚

20˚

10˚

65˚

0.9 – 1.3 mm
(0.04 – 0.05 in)

AK300719AD

CUT

0.5 – 1 mm
(0.02 – 0.04 in)

AK300720AD

OVERSIZE HOLE
DIAMETER

VALVE SEAT
HEIGHT

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