Chery A series. Instruction - page 10
COMPRESSION PRESSURE
COMPRESSION INSPECTION
Warning
·Hot engines and oil can cause severe burns. Be careful not to burn yourself during
removal/installation of each component.
1. Verify that the battery is fully charged.
·Recharge it if necessary.
2. Warm up the engine to the normal operating temperature.
3. Stop the engine and allow it to cool off for about 10 min.
4. Perform “Fuel Line Safety Procedures”. Leave the fuel pump relay removed.
Warning
·Fuel vapor is hazardous. It can very easily ignite, causing serious injury and damage.
Always keep sparks and flames away from fuel.
·Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries
or death and damage. Fuel can also irritate skin and eyes. To prevent this, always
complete the “Fuel Line Safety Procedure”.
5. Remove the ignition coil connector.
6. Remove the spark plugs.
7. Connect a compression gauge into the spark plug
hole.
8. Fully depress the accelerator pedal and crank the
engine.
9. Note the maximum gauge reading.
10. Inspect each cylinder as above.
·If the measured value is less than the limited value, or there is a cylinder whose
compression value varies from that of other cylinders, add a small amount of engine oil
through the spark plug hole. Then measure the compression pressure and perform the
respective operations for the following cases.
— If the compression increases, the piston, the piston rings, or cylinder wall may be worn
and overhaul is required.
— If the compression stays low, a valve may be stuck or improperly seated and overhaul is
required.
— If the compression in adjacent cylinders stays low, the cylinder head gasket may be
damaged or the cylinder head distorted and overhaul is required.
B-17
Cylinder Pressure Standard Value:1.00-1.35 Mpa (10-13.5 kgf/cm2)
11. Disconnect the compression gauge.
12. Install the spark plugs.
13. Connect the ignition coil connector.
14. Install the fuel pump relay.
B-18
CYLINDER HEAD GASKET
CYLINDER HEAD GASKET
REPLACEMENT
Removal
Rotate the cam shaft clockwise until the key slot
goes downwards vertically.
Loosen the bolts on the cylinder head in the order
illustrated in the figure.
Note: The bolts removed from the cylinder head
must be changed and cannot be reused.
Inspection and Installation
Check the out-of-flat of the base plane of the
cylinder head, which shall not be above 0.15mm.
Clean the threaded holes of the cylinder block. No
lubricant shall be settled in the threaded holes,
otherwise the liquid pressure may lead to the
cracking of the cylinder block after the bolts are
screwed in.
Rotate the crank shaft clockwise to the position
that enables the piston of the first cylinder to be
about 20mm lower than the top plane of the
cylinder block, thus to avoid the valve to collide
with the top of the piston when installing the
cylinder head assembly.
B-19
Put the cylinder gasket into the dowel.
Note: The side with indicator of the cylinder
gasket shall be upward.
Install the cylinder head in place with the key slot
of the cam shaft downward vertically.
Note: The cylinder gasket can only be used for
one time, so the removed one shall be
replaced with a new one when removing
the cylinder head.
Put the bolts and the flat gasket of the cylinder
head into the threaded hole to screw them in by
hands.
Tighten the bolts of the cylinder head in four steps
according to the order illustrated in the figure:
a. First step: tighten it at the moment of
20-40N.
b. Second step: tighten it at the moment of
20-40N.
c. Third step: rotate 90 degrees.
d. Fourth step: rotate 90 degrees.
e.
Moment-angular tension indicating
wrench can be used for degree rotation.
A. Location Pin B. Gasket
B-20