Chery SQR 7160 sedan. Manual — part 28
CAC Gasoline Engine Maintenance And Servicing Manual
30
——Camshaft journal and cylinder head cam bearing
hole size：
(1) Standard size mm
(2). Over size (0.38) mm
mm
Installation：
——If camshaft needs to be replaced, check the shape of the
rear end of camshaft to select appropriate camshaft.
——Before installation，apply hypoid gear oil or engine oil
on camshaft cams, assembly camshaft from behind the
cylinder head forward.
——Apply engine oil on camshaft thrust spacer，insert thrust
washer into the groove in the cylinder head.
——Screw 2 bolts into thrust washer tapped holes,
tightening torque is 9—13Nm.
——Check camshaft end play，end play should be as
specified.
——When the hydraulic lifting rod of oversize 0.25 is
applied, camshaft must be selected, or the hydraulic lifting
rod may be stuck.
Camshaft
journal number
Camshaft journal
diameter
Cylinder head
bearing hole
diameter
1
44.74—44.76
44.783—44.808
2
44.99—45.01
45.033—45.058
3
45.24—45.26
45.283—45.308
4
45.49—45.51
45.533—45.558
5
45.74—45.76
45.783—45.808
Camshaft journal
number
Camshaft journal
diameter
Cylinder head
bearing hole
diameter
1
45.12—45.14
45.163—45.188
2
45.37—45.39
45.413—45.438
3
45.62—45.64
45.663—45.688
4
45.87—45.89
45.913—45.938
5
46.12—46.14
45.163—45.188
bolt
Tightening torque
Thrust
washe
r
Fig.35
Fig. 36
Fig. 37
CAC Gasoline Engine Maintenance And Servicing Manual
31
5.Valve, valve spring, valve oil seal, spring seat assembly
removal and
installation：
Removal：
Using special tools for valve compression, take out valve
locking pieces, don't compress spring excessively, compress
spring enough to slip locking pieces out of its stroke, or valve
stem may be bent.
If valve locking pieces do not come out during spring
compression, remove compression tools, put an appropriate
pipe on spring seat， so the valve locking piece will not be
impacted. Put a wooden block on valve head (with cylinder
head combustion chamber facing workbench), and then strike
pipe end with hammer.
Reinstall special tools for valve spring compression, locking
pieces may be taken out. After locking piece is taken out,
remove compression tools by unbolting slowly.
——Remove valve spring seat and valve spring，take out
valve oil seal spring seat assembly with screwdriver， and
valve oil seal spring seat must be replaced.
——Overturn cylinder head ，remove intake and exhaust
valves.
——Keep each set of valve, valve locking pieces, valve
spring, spring seat in the same plastic bag and mark numbers
on it, so the parts may be installed in the original place.
——Valve standard sizes and clearance：
Unit：Mm
Intake valve
Exhaust valve
grade
Valve stem
diameter
Valve guide
hole
diameter
Clearance
Valve stem
diameter
Valve guide
hole
diameter
Clearance
standard
8.043+0
-0.018
8.063-8.094
8.017+0
-0.018
8.063-8.094
oversize0.4
8.443+0
-0.018
8.463-8.494
0.02-0.069
8.417+0
-0.018
8.463-8.494
0.046-0.095
Fig.38
Fig. 39
Fig. 40
CAC Gasoline Engine Maintenance And Servicing Manual
32
——Measure valve spring free length and spring force:
——Grinding the valve and the valve seat with the valve
conical angle(Intake valve and exhaust valve):
44°30′— 45°30′
valve seat sealing width:
1.75 — 2.32mm
Installation:
——Before installation, make sure that cylinder head has been
cleaned without any grinding material on cylinder head, valve or
valve guide .
——Lubricate the valve stem and guide with clean engine oil.
——Install the valve. notice that the intake and exhaust valve for 478
and 480 are not interchangeable .refer to the previous valve mark for
valve assembly.
——Press the valve spring assembly with oil seal onto the top of
valve guide. apply engine oil on the intake and exhaust valve guide
edge where the valve seals are installed for preventing valve lock
piece groove from damaging oil seal lip. You may protect the valve
lock groove with tape and remove the tape after installing the valve.
——Install the valve spring and spring seat. Compress the spring seat
to expose the lock piece groove with a special compression tool. Then
put the lock pieces into it and release the compression tool slowly and
remove the tool .
——Put the cylinder head on a wood lump after all lock pieces are
assembled. And tap the small head of the valve stem with a plastic or
copper hammer to fit for the valve mechanism.
Compression (mm)
Spring load (N)
Spring free length
L
1
=37.084
422
L
2
=27.7
892.7
L
3
=27.0
945
L
0
=47.2
Fig.42
Fig.43
Fig.44
Fig.45
Fig.42
CAC Gasoline Engine Maintenance And Servicing Manual
33
6.the sizes for intake valve, intake valve seat, exhaust valve seat and valve guide
―the size of intake valve seat and cylinder head valve seat hole
―
the size of exhaust valve seat and cylinder head valve seat hole
—
——the size of valve guide and valve guide hole
Diameter. of intake
valve seat
Diameter of the
cylinder head
valve seat hole
press fit
clearance
Standard
478
41.877
+0.01
-0.01
41.763
+0.025
0
oversize
0.5
42.377
+0.01
-0.01
42.263
+0.025
0
oversize
1.0
42.877
+0.01
-0.01
42.763
+0.025
0
0.079—0.124
Standard
480
43.877
+0.01
-0.01
44.763
+0.025
0
oversize
0.5
44.377
+0.01
-0.01
44.263
+0.025
0
oversize
1.0
44.877
+0.01
-0.01
44.763
+0.025
0
0.079—0.124
Diameter. of intake
valve seat
Diameter of the
cylinder head
valve seat hole
press fit
clearance
Standard
478
35.377
+0.01
-0.01
35.263
+0.025
0
oversize 0.5
35.877
+0.01
-0.01
35.763
+0.025
0
oversize 1.0
36.377
+0.01
-0.01
36.263
+0.025
0
0.079—0.124
Standard
480
38.377
+0.01
-0.01
38.263
+0.025
0
oversize 0.5
38.877
+0.01
-0.01
38.763
+0.025
0
oversize 1.0
39.377
+0.01
-0.01
39.263
+0.025
0
0.079—0.124
Level
The valve guide
hole
The diameter. of
cylinder head tube
hole
press fit
clearance
Standard
13.555
0
-0.01
13.481-13.519
oversize
14.305
0
-0.01
14.231-14.269
oversize
14.505
0
-0.01
14.481-14.519
0.026-0.07
Fig.46
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