Geely CK Series 2007 Workshop Manual page 87

3. Piston knocking noise causes and troubleshooting
No.
Main bearing oil channel depth and width
misalined or insufficient oil pressure result
Knock when
in poor lubrication of the cylinder wall
engine is cold
Excessively big clearance between the
Connecting rod journal is not parallel with
Connecting rod bushing axial declination
Knock when
Excessively small clearance between the
engine is hot
Excessively small backlash and end gap for
Poor lubrication for cylinder wall and piston
Piston pin and connecting rod end are
Knock no
matter the
Connecting rod bearing is assembled too
engine is cold
or hot
80
Item
piston and the cylinder wall
Connecting rod bent
the main journa l
Pistion counter ellipse
p istion and cylinder wal l
the piston ring.
installed too tightly
tightly
Piston skirt ovality is too big
Troubleshooting
Repair or adjust the oil pressure to
specification
Replace the piston to resume the normal
clearance
Correct or replace the connecting rod
Replace the connecting rod
Replace the bushing
Replace the piston
Repair the cylinder or replace the piston
Repair or replace the piston ring
Dredge the oil line to improve the
lubricant splashing problem
Adjust piston pin tension to normal level
Adjust the bearing tension to normal level
Replace the piston with normal ovalit y