Chpter IV Mechanical System
Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited
185
Fig. 4-5-20 Measurement for axial clearance
of connecting rod
Fig. 4-5-21 Measurement for oil clearance
between the connecting rod and the
crankshaft
the connecting rod big end. See Fig. 4-5-20.
Replace the connecting rod if the measured value
exceeds the limitation.
Axial clearance of connecting rod
Standard
0.15~0.32mm
5.3 Checking the oil clearance between the
connecting rod bearing shell and crank pin
(1) Remove the connecting rod cover bolts and the
connecting rod covers.
(2) Place the removed connecting rod covers properly
according to the cylinder sequence number.
(3) Clean the surfaces of connecting rod bearing shells
and crank pins.
(4) Carefully check the connecting rod bearing shells for
damage. Replace all connecting rod bearing shells
even if only one bearing shell is damaged or heavily
worn.
(5) Install the connecting rod bearing shells to their
original positions.
(6) Place the plastic precision clearance gauge on the
crank pin.
(7) Install the connecting rod covers to their original
positions.
Screw down the connecting rod cover bolts as per the
specified torque by two steps.
Step 1 (touching torque)
Step 2 (final torque)
25N·
m±3N·
m
Turning angle 90°
Fig. 4-5-22 Measurement for width of plastic
precision clearance gauge and determination
of oil clearance
Attention:
The crankshaft should not rotate when
you screwing down the connecting rod cover bolts.
(9) Remove the connecting rod covers.
(10) Measure the width of plastic precision clearance
gauge and determine the oil clearance. See Fig.
4-5-22.Replace the connecting rod bearing shell in
group if the clearance exceeds the limitation.
(11) Remove the plastic precision clearance gauge from
the crank pin.
Oil clearance between the connecting rod bearing shell
and crank pin
Standard
0.020~0.048mm
Reassembly
Reinstalling the piston component
⑩
