4A–FE engine is an in–line, 4–cylinder, 1.6 liter DOHC 16–valve engine. Manual — part 12
33. REMOVE CYLINDER HEAD
(a) Using SST, uniformly loosen and remove the ten
cylinder head bolts in several passes in the sequence
shown.
SST 09205–16010
NOTICE: Cylinder head warpage or cracking could
result from removing bolts in incorrect order.
(b) Remove the ten plate washers.
(c) Lift the cylinder head from the dowels on the cylinder block
and place the head on wooden blocks on
a bench.
HINT: If the cylinder head is difficult to lift off, pry with
a screwdriver between the cylinder head and block
saliences.
NOTICE: Be careful not to damage the contact surfaces of
the cylinder head and cylinder block.
(e) Remove the following parts:
(1) Wave washer
(2) Camshaft sub–gear
(3) Camshaft gear spring
32. REMOVE SEMI–CIRCULAR PLUG
(d) Using snap ring pliers, remove the snap ring.
–
ENGINE MECHANICAL
Cylinder Head (4A–FE)
EM–90
2. REMOVE VALVES
(a) Using SST, compress the valve spring and remove
the two keepers.
SST 09202–70010
(b) Remove the spring retainer, valve spring, valve and
spring seat.
DISASSEMBLY OF CYLINDER HEAD
(See page
EM–81
)
1. REMOVE VALVE LIFTERS AND SHIMS
HINT: Arrange the valves, valve springs, spring seats
and spring retainers in correct order.
HINT: Arrange the valve lifters and shims in correct
order.
(c) Using needle–nose pliers, remove the oil seal.
–
ENGINE MECHANICAL
Cylinder Head (4A–FE)
EM–91
INSPECTION, CLEANING AND REPAIR
OF CYLINDER HEAD COMPONENTS
1. CLEAN TOP SURFACES OF PISTONS AND CYLINDER
BLOCK
(a) Turn the crankshaft and bring each piston to top
dead center (TDC). Using a gasket scraper, remove
all the carbon from the piston top surfaces.
2. CLEAN CYLINDER HEAD
A. Remove gasket material
Using a gasket scraper, remove all the gasket material
from the surface contacting the cylinder block.
NOTICE: Be careful not to scratch the cylinder block
contact surface.
(b) Using a gasket scraper, remove all the gasket material
from the surface contacting the cylinder head.
(c) Using compressed air, blow carbon and oil from the
bolt holes.
CAUTION: Protect your eyes when using high–pres-
sure compressed air.
B. Clean combustion chambers
Using a wire brush, remove all the carbon from the
combustion chambers.
NOTICE: Be careful not to scratch the cylinder block
contact surface.
C. Clean valve guide bushings
Using a valve guide bushing brush and solvent, clean all
the guide bushings.
–
ENGINE MECHANICAL
Cylinder Head (4A–FE)
EM–92
3. INSPECT CYLINDER HEAD
A. Inspect for flatness
Using precision straight edge and feeler gauge, measure
the surfaces contacting the cylinder block and manifolds
for warpage.
Maximum warpage:
Cylinder block side 0.05 mm (0.0020 in.)
Manifold side 0.10 mm (0.0039 in.)
If warpage is greater than maximum, replace the cylinder
head.
B. Inspect for cracks
Using a dye penetrant, check the combustion chambers,
intake ports, exhaust ports and cylinder block surface for
cracks.
If cracked, replace the cylinder head.
D. Clean cylinder head
Using a soft brush and solvent, thoroughly clean the
cylinder head.
4. CLEAN VALVES
(a) Using a gasket scraper, chip off any carbon from the
valve head.
(b) Using a wire brush, thoroughly clean the valve.
–
ENGINE MECHANICAL
Cylinder Head (4A–FE)
EM–93
(b) Using a micrometer, measure the diameter of the
valve stem.
Valve stem diameter:
Intake
5.970 – 5.985 mm
(0.2350 – 0.2356 in.)
Exhaust
5.965 – 5.980 mm
(0.2348 – 0.2354 in.)
(c) Subtract the valve stem diameter measurement from
the guide bushing inside diameter measurement.
Standard oil clearance:
Intake
0.025 – 0.060 mm
(0.0010 – 0.0024 in.)
Exhaust
0.030 – 0.065 mm
(0.0012 – 0.0026 in.)
Maximum oil clearance:
Intake
0.08 mm (0.0031 in.)
Exhaust
0.10 mm (0.0039 in.)
If the clearance is greater than maximum, replace the
valve and guide bushing.
5. INSPECT VALVE STEMS AND GUIDE BUSHINGS
(a) Using a caliper gauge, measure the inside diameter
of the guide bushing.
Bushing inside diameter:
6.010 – 6.030 mm (0.2366 – 0.2374 in.)
6. IF NECESSARY, REPLACE VALVE GUIDE BUSHINGS
(a) Gradually heat the cylinder head to 80 –100
В°
C (176
– 212
В°
F).
(b) Using SST and a hammer, tap out the guide
bushing.
SST 09201–70010
–
ENGINE MECHANICAL
Cylinder Head (4A–FE)
EM–94
(d) Select a new guide bushing (STD or O/S 0.05).
If the bushing bore diameter of the cylinder head is
greater than 11.027 mm (0.4341 in.), machine the bushing
bore to the following dimension:
11.050 –11.077 mm (0.4350 – 0.4361 in.)
If the bushing bore diameter of the cylinder head is
greater than 11.077 mm (0.4361 in.), replace the cylinder
head.
(f) Using SST and a hammer, tap in a new guide bushing
until there is 12.7 –13.1 mm (0.500 – 0.516 in.)
protruding from the cylinder head.
SST 09201–70010
(g) Using a sharp 6 mm reamer, ream the guide bushing
to obtain the standard specified clearance (See
page
EM–94
) between the guide bushing and valve
stem.
(e) Gradually heat the cylinder head to 80 –100
В°
C (176
– 212
В°
F).
(c) Using a caliper gauge, measure the bushing bore
diameter of the cylinder head.
Bushing bore diameter
mm (in.)
Both intake and exhaust
Bushing size
–
ENGINE MECHANICAL
Cylinder Head (4A–FE)
EM–95
(d) Check the valve overall length.
Standard overall length:
Intake 91.45 mm (3.6004 in.)
Exhaust 91.90 mm (3.6181 in.)
Minimum overall length:
Intake 90.95 mm (3.5807 in.)
Exhaust 91.40 mm (3.5984 in.)
If the overall length is less than minimum, replace the
valve.
(c) Check the valve head margin thickness.
Standard margin thickness: 0.8 –1.2 mm
(0.031 – 0.047 in.)
Minimum margin thickness: 0.5 mm (0.020 in.)
If the margin thickness is less than minimum, replace
the valve.
7. INSPECT AND GRIND VALVES
(a) Grind the valve enough to remove pits and carbon.
(b) Check that the valve is ground to the correct valve
face angle.
Valve face angle: 44.5
В°
(e) Check the surface of the valve stem tip for wear.
If the valve stem tip is worn, resurface the tip with a
grinder or replace the valve.
NOTICE: Do not grind off more than minimum.
8. INSPECT AND CLEAN VALVE SEATS
(a) Using a 45
В°
carbide cutter, resurface the valve seats.
Remove only enough metal to clean the seats.
–
ENGINE MECHANICAL
Cylinder Head (4A–FE)
EM–96
(b) Check the valve seating position.
Apply a light coat of prussian blue (or white lead) to
the valve face. Lightly press the valve against the
seat. Do not rotate the valve.
(c) Check the valve face and seat for the following:
•
If blue appears 360
В°
around the face, the valve is
concentric. If not, replace the valve.
•
If blue appears 360
В°
around the valve seat, the
guide and face are concentric. If not, resurface the
seat.
•
Check that the seat contact is in the middle of the
valve face with the following width:
1. 2 –11.6 mm (6.047 – 0.063 in.)
If not, correct the valve seats as follows:
(1) If the seating is too high on the valve face, use
30
В°
and 45
В°
cutters to correct the seat.
9. INSPECT VALVE SPRINGS
(a) Using a steel square, measure the squareness of the
valve spring.
Maximum squareness: 2.0 mm (0.079 in.)
If squareness is greater than maximum, replace the valve
spring.
(d) Hand–lap the valve and valve seat with an abrasive
compound.
(e) After hand–lapping, clean the valve and valve seat.
(2) If the seating is too low on the valve face, use
60
В°
and 45
В°
cutters to correct the seat.
–
ENGINE MECHANICAL
Cylinder Head (4A–FE)
EM–97
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