Downloaded from www.Manualslib.com manuals search engine CONDITIONPOSSIBLE CAUSE CORRECTION
Engine Miss On Acceleration 1. Dirty or incorrectly gapped spark
plugs.
2. Contamination in fuel system.
7. Burned, warped, excessive
clearance, or pitted valves.
4. Faulty ignition coil(s).1. Clean spark plugs and set gap.
2. Clean fuel system and replace
fuel filter.
3. Replace valves.
4. Test and replace if necessary.
(Refer to Appropriate Diagnostic
Information)
Engine Miss At High Speed 1. Dirty or incorrect spark plug gap.
2. Faulty ignition coil(s).
3. Dirty fuel injector(s).
4. Contamination in fuel system.1. Clean spark plugs and set gap.
2. Test and replace if necessary.
(Refer to Appropriate Diagnostic
Information)
3. Test and replace if necessary.
(Refer to Appropriate Diagnostic
Information)
4. Clean system and replace fuel
filter.
Engine Mechanical Diagnostics
CONDITION
POSSIBLE CAUSE CORRECTION
Valve Train Noise 1. High or low oil level in crankcase.
2. Thin or diluted oil.
3. Thick oil.
4. Low oil pressure.
5. Worn cam lobe.
6. Worn valve guides.
7. Excessive runout of valve seats
on valve faces.1. Check and correct engine oil
level.
2. Change oil to correct viscosity.
3. Change engine oil and filter.
4. Check and correct engine oil
level.
5. Install new camshaft.
6. Replace cylinder head.
7. Grind valve seats and replace
valves.
Connecting Rod Noise 1. Insufficient oil supply.
2. Low oil pressure.
3. Thin or diluted oil.
4. Excessive bearing clearance.
5. Connecting rod journal out-of-
round.
6. Connecting rod out-of-round.
7. Misaligned connecting rods.
8. Connecting rod nuts loose.1. Check engine oil level.
2. Check engine oil level. Inspect oil
pump relief valve and spring.
3. Change oil to correct viscosity.
4. Measure bearings for correct
clearance. Repair if necessary.
5. Replace crankshaft or grind
surface.
6. Replace connecting rod.
7. Replace bent connecting rods.
8. Tighten the connecting rod nuts.
Main Bearing Noise 1. Insufficient oil supply.
2. Low oil pressure.
3. Thin or diluted oil.
4. Excessive bearing clearance.
5. Excessive end play.
6. Crankshaft journal out-of-round or
worn.
7. Loose flywheel or torque
converter.1. Check engine oil level.
2. Check engine oil level. Inspect oil
pump.
3. Change oil to correct viscosity.
4. Measure bearings for correct
clearance. Repair if necessary.
5. Check thrust bearing for wear on
flanges.
6. Replace crankshaft or grind
journals.
7. Tighten to correct torque.
DIAGNOSIS & TESTING
02–88Chery Automobile Co., Ltd.
Downloaded from www.Manualslib.com manuals search engine CONDITIONPOSSIBLE CAUSE CORRECTION
Oil Pressure Drop 1. Low oil level.
2. Faulty oil pressure sending unit.
3. Low oil pressure.
4. Clogged oil filter.
5. Thin or diluted oil.
6. Excessive bearing clearance.1. Check engine oil level.
2. Install new sending unit.
3. Check sending unit and main
bearing oil clearance.
4. Install new oil filter.
5. Change oil to correct viscosity.
6. Measure bearings for correct
clearance.
Oil Leaks 1. Misaligned or deteriorated
gaskets.
2. Loose fastener, broken or porous
metal part.
3. Misaligned or deteriorated cup or
threaded plug.1. Replace gasket.
2. Tighten, repair or replace the part.
3. Replace if necessary.
Oil Consumption Or Spark Plugs
Fouled 1. PCV system malfunction.
2. Worn, scuffed or broken rings.
3. Carbon in oil ring slots.
4. Rings fitted too tightly in grooves.
5. Worn valve guide(s).
6. Valve stem seal(s) worn or
damaged.1. Check system and repair if
necessary.
2. Hone cylinder bores. Install new
rings.
3. Install new rings.
4. Remove rings and check grooves.
If groove is not proper width, replace
piston.
5. Replace cylinder head.
6. Replace seal(s).
DIAGNOSIS & TESTING
02
02–89Chery Automobile Co., Ltd.
Downloaded from www.Manualslib.com manuals search engine Cylinder Compression Pressure Test
•The result of a cylinder compression pressure test can be utilized to diagnose several engine malfunctions.
• Ensure the battery is completely charged and the engine starter motor is in good operating condition. Otherwise
the indicated compression pressures may not be valid for diagnostic purposes.
Check engine oil level and add oil if necessary.
Disconnect the spark plug wires.
Remove all spark plugs from engine (as spark plugs are being removed, check electrodes for abnormal
firing indicators fouled, hot, oily, etc.).
Record cylinder number of each spark plug for future reference.
Disconnect fuel injector electrical connectors.
Be sure throttle blade is fully open during the compression check.
Insert compression pressure adaptor or the equivalent into each spark plug hole in cylinder head.
Crank engine until maximum pressure is reached on gauge. Record each cylinder pressure.
Compression should not be less than 1000 kPa and not vary more than 25 percent from cylinder to cylinder.
If one or more cylinders have abnormally low compression pressures, repeat the compression test.
If the same cylinder or cylinders repeat an abnormally low reading on the second compression test, it could indicate the existence of a problem with the cylinder in question.
NOTE :
The recommended compression pressures are to be used only as a guide to diagnosing engine problems. An engine
should not be disassembled to determine the cause of low compression unless some malfunction is present.
Cylinder Head Gasket Test
• A cylinder head gasket leak can be located between adjacent cylinders, between a cylinder and the adjacent
water jacket or from an oil passage to the exterior of the engine.
• Possible indications of the cylinder head gasket leaking between adjacent cylinders are:
Loss of engine power
Engine misfiring
Poor fuel economy
• Possible indications of the cylinder head gasket leaking between a cylinder and an adjacent water jacket are:
Engine overheating
Loss of coolant
Excessive steam (white smoke) emitting from exhaust
Coolant foaming
DIAGNOSIS & TESTING
02–90Chery Automobile Co., Ltd.
Downloaded from www.Manualslib.com manuals search engine ENGINE UNIT REPAIR
Engine Block
Specifications
Torque Specifications
DESCRIPTIONTORQUE (N·m)
Connecting Rod Cap Bolts 1st Step: Tighten the bolt to 25 N·m
2nd Step: Tighten the bolt an additional 90°
Main Bearing Cap Bolts 1st Step: Tighten the bolt to 45 N·m
2nd Step: Tighten the bolt an additional 180°
Lower Cylinder Block Bolts 23
Clearance Specifications
DESCRIPTIONSPECIFICATION (mm)
Surface Distortion Limit 0.15
Inner Diameter Standard 84
Out-Of-Round < 0.008
Taper < 0.01
Disassembly
1. Remove the oil pan and then remove oil baffle.
2. Remove the oil strainer.
3. For each connecting rod/piston assembly to be removed, rotate the crankshaft to the bottom dead center position
for each cylinder.
NOTE :
Before removing the connecting rod/piston assembly, check the connecting rod side clearance.
BESM020060
02–123Chery Automobile Co., Ltd.
Downloaded from www.Manualslib.com manuals search engine Inspection
NOTE :
All measurements should be taken with the engine block at room temperature, 21°C.
Engine Block
•Clean cylinder block thoroughly and check all core hole plugs for evidence of leaking.
• Examine block and cylinder bores for cracks or fractures.
• Check block deck surfaces for flatness. Deck surface must be within service limit of 0.050 mm.
Cylinder Bore
• The cylinder walls should be checked for out-of-round and taper with cylinder indicator or equivalent. If the cyl-
inder walls are badly scuffed or scored, the cylinder block should be replaced, and new pistons and rings fitted.
• Measure the cylinder bore at three levels in directions X and Y. Top measurement should be 10 mm down and
bottom measurement should be 10 mm up from
bottom of bore.
CYLINDER BORE
All Cylinders 83.500 - 83.510 mm
Assembly
NOTE :
Cleanliness is extremely important during the engine assembly procedure. Any foreign material, including any mate-
rial created while cleaning gasket surfaces, that enters the oil passages, coolant passages or the oil pan can cause
engine failure.
NOTE :
Assemble all components in their original position.
1. Install the pistons to the connecting rods.
2. Using a piston ring expander, install the piston rings.
3. Assemble all components in the reverse order of disassembly.
ENGINE UNIT REPAIR
BESM020063
02–125Chery Automobile Co., Ltd.