Geely CK (2008). Manual part — 20
Geely CK (2008). Manual part - 20
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IV. Exhaust Pipe Discharges Gas with Abnormal Color (or odor)
When there is failure in engine combustion system, the exhaust pipe discharges gas with abnormal color.
1. The discharged gas is thickly black
This is caused by incomplete combustion. Since the mixed air is too thick, the combustion is not complete and
part of the fuel is discharged without combustion, leading to decrease of engine power. At this moment, you
should check fuel pressure regulator, throttle position sensor, injector and ECU system and correct the
problems in time.
2. Exhaust is blue and stinks
This is caused by large amount of oil vapor mixed in the exhaust gas that enters in the cylinder and partici-
pates in combustion. One of the primary reasons is that the piston oil ring is dirty and damaged, and shall be
replaced; another reason may be the failure of valve oil seal or excessive clearance between the valve stem
and guide bush hole resulting in oil entering the combustion chamber for combustion, oil seal or valve guide
bush shall be replaced to resume normal condition.
3. Exhaust is white
This is caused by water or fuel vapor mixed in the exhaust. The primary reason is that cylinder head gasket
is damaged, resulting in slow infiltration of coolant into cylinder and the water vapor entry into the exhaust
pipe after combustion, cylinder head gasket shall be replaced to resume the normal condition.
Section 3 Engine Noise Diagnosis and Troubleshooting
Abnormal sounds generated during engine operation (e.g. knocking sound, chuckle, hiss, rattle) are called
noise.
Engine noise is primarily generated in valve train, connecting rod piston crankshaft components and other
accessory system. The following description discusses the diagnosis and troubleshooting of the noise gener-
ated in valve train and crankshaft connecting rod mechanism.
I. Diagnosis and troubleshooting of the noise in valve train
valve train consists of intake & exhaust camshaft , valve, valve bushing, tappetand counter gear.
1. camshaft noise
(1) camshaft end play is excessively big (normal intake camshaft : 0.030~0.085mm, exhaust camshaft : 0.
035~0.090mm) , when it exceeds 0.11mm and noise is generated, replace it;
(2) Camshaft bend is another cause for noise; it shall be aligned or scraped. ;
(3) Camshaft journal is excessively worn, resulting in big radial clearance between camshaft and bearing and
noise, replace it;
2. Valve group knock noise
(1) Valve noise is caused by excessive valve clearance, the valve spring seat flange is damaged and shall be
replaced;
(2) Valve spring knock noise is caused by broken valve spring. It shall be replaced;
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(3) Valve free movement noise is caused by dropped valve keeper or broken valve head. It shall be replaced;
(4) Noise between the intake & exhaust valve and valve bushing is caused by stagnation valve and bushing
that can not be closed, repair the bushing or replace it;
(5) Valve and valve seat can not be tightly closed and noise is generated, leading to abnormal engine operation.
Valve shall be grinded to fit, otherwise it shall be replaced.
3. Gear noise is mainly caused by excessive wear of the gear which results in excessive clearance,
generating the noise during the operation. The counter gear shall be replaced.
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II. Crankshaft connecting rod noise diagnosis and troubleshooting
1. crankshaft connecting rod noise cause and troubleshooting
2. Piston ring leakage, knock and noise causes and troubleshooting
Noise cause
Elimination method
Piston ring broken
Replace
Excessive piston ring backlash
Replace
Piston ring contra aperture
Correct (stagger)
Piston ring is locked
Replace
Insufficient elasticity of the piston ring
Replace
Poor seal between te piston and cylinder wall
Replace
No.
Noise area
Noise cause
Troubleshooting
Excessive connecting rod bearing radial
play
Replace the bearing
Connecting rod cover bolt loosened
Tighten
Connecting rod bearing insert dimension
not as specified result in rotation or
rupture
Replace the insert
Connecting rod bearing insert burned
Replace the insert
Poor lubrication for connecting rod
bearing
Drill the lubricant hole to normal,
improve the lubricant line
Excessive main bearing raidal play
Replace the main bearing
Main bearing cover bolt loosened
Tighten
Main bearing insert burned
Replace the insert
Poor lubrication for main bearing
Smoothen the lubricant line or
enlarge the oil hole
Main bearing insert dimension not as
specified result in rotation or rupture
Replace the main bearing insert
Excessive crankshaft bearing raidal play
Adjust (pad) to normal
Excessive wear of the cranshaft thrust
washer
Replace the thrust washer
4
Flywheel
impact noise
Flywheel set bolt loosened
Tighten
3
Crankshaft
axial runout
noise
Connecting rod
bearing noise
1
Main bearing
noise
2
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3. Piston knocking noise causes and troubleshooting
No.
Item
Troubleshooting
Main bearing oil channel depth and width
misalined or insufficient oil pressure result
in poor lubrication of the cylinder wall
Repair or adjust the oil pressure to
specification
Excessively big clearance between the
piston and the cylinder wall
Replace the piston to resume the normal
clearance
Connecting rod bent
Correct or replace the connecting rod
Connecting rod journal is not parallel with
the main journal
Replace the connecting rod
Connecting rod bushing axial declination
Replace the bushing
Pistion counter ellipse
Replace the piston
Excessively small clearance between the
pistion and cylinder wall
Repair the cylinder or replace the piston
Excessively small backlash and end gap for
the piston ring.
Repair or replace the piston ring
Poor lubrication for cylinder wall and piston
Dredge the oil line to improve the
lubricant splashing problem
Piston pin and connecting rod end are
installed too tightly
Adjust piston pin tension to normal level
Connecting rod bearing is assembled too
tightly
Adjust the bearing tension to normal level
Piston skirt ovality is too big
Replace the piston with normal ovality
Knock when
engine is cold
Knock when
engine is hot
Knock no
matter the
engine is cold
or hot
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