Chery A18. Manual — part 31

ROCKER MECHANISM

Removal

Loosen the rocker nuts to take them out.

Take the level bracket out.

Take the rocker arm out.

Take the gasket of the level bracket out.

Place each set of rock arm and level
bracket in one same plastic bag for
distinction. The removed rocker nuts
cannot be reused.

Installation:

Check whether theire is abnormal abrasion on
the contact surface of the rocker. Replace it if
necessary.

Put the rocker seat gasket into the stud.

Lubricate the rocker arm and rocker seat by
motor oil.

Install the rocker arm and seat, screw in the
new nuts by hands, then tighten them for the
moment of 25—29N.m.

Note: The corresponding hydraulic

tappet shall be in the Min.
position before each rocker
arm is installed and tightened
with nuts.

HYDRAULIC TAPPET

Removal

Take the hydraulic tappets out and place them
into an oil-filled vessel to prevent the hydraulic
tappet oil from leaking out.

Check the top and bottom contact surfaces of
the hydraulic tappet to observe whether there
are abnormal abrasion or scrapes. If yes,
replace it with new one if necessary.

Installation
Apply hyperbolic gear oil or motor oil on the
tappet and external diameter as well as its two
ends and place the tappet into the cylinder
head hole in the original order.

Size of Hydraulic Tappet

Class

Outside circle diameter

(unit: mm)

Hole diameter of the cylinder

head tappet (unit: mm)

Fit clearance

(unit: mm)

Standard

￠22.200~￠22.212

￠22.25±0.015

0.023~0.065

T25

￠22.454~￠22.466

￠22.50±0.015

0.023~0.065

Tappet

VALVE, VALVE SPRING AND OIL SEAL
ASSEMBLY OF THE VALVE

Removal

Compress the valve spring with a special
compression device and take the valve cotter out.
Do not over compress the spring, which shall be
compressed to the travel stroke that the valve
cotter can slide from the groove, otherwise the
valve stem may bend.

If the valve cotter cannot slide out when the spring
is compressed, remove the compression device and
place a proper pipe on the spring seat. In this way,
the valve cotter will not be collided. Place a piece
of wood on the valve head (with the side of the
combustion chamber of the cylinder head towards
the table) and then hammer at the top of the pipe.

Reinstall the special compression device and
compress the valve spring to take the cotter out.
After the valve cotter is taken out, slowly loosen
the bolts to remove the compression device.

Remove the valve spring seat and valve spring and
take the valve oil seal and spring seat assembly out
with a screwdriver. The seal oil seal spring seat
must be replaced.

Put one set of valve, valve cotter, spring and spring
seat into one plastic bag, each of which shall be
tagged with numbers for installing them back to the
original position.

CYLINDER

1

Valve stem size and fit clearance

Intake（mm）

Exhaust（mm）

Class

Diameter of

valve stem

Inner

Diameter of

valve guide

Clearance

Diameter

of valve

stem

Inner Diameter

of valve guide

Clearance

Standard 8.043

0

018

.

0

+

−

8.063—8.094

8.017

0

018

.

0

+

−

8.063—8.094

Oversized

0.4

8.443

0

018

.

0

+

−

8.463—8.494

0.02—

0.069

8.417

0

018

.

0

+

−

8.463—8.494

0.046—

0.095

Measure the free length and elasticity of the
valve spring

Compression

length (mm)

Spring load

(N)

Free Length

of Spring

(mm)

L

1

=37.084

422

L

2

=27.7

892.7

L

3

=27.0

945

L

0

=47.2