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1. Assembly & Disassembly Manual
Gas Engine
Model: WP10GTA
WEICHAI AMERICA CORP.
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2. Weichai America Corp.
1
Purpose
This manual is intended to inform customers on how to assemble and disassemble the Weichai
America 10 Liters turbocharged engine. This document will be provided to customer so they can
incorporate this information into their manuals and service documents.
Maintenance Providers
Maintenance and repair services may be performed by you or any qualified engine service provider
that you choose. However, your engine warranty does not cover damage or failure caused by
improper maintenance or repairs.
Owner’s Manual & Maintenance Records Storage & Use
Store this Owner’s Manual and Maintenance Records in a safe, visible place by your engine. The
maintenance log must be updated whenever your engine is serviced. If repairs are being done under
warranty should be sure to follow proper warranty procedures. (See Weichai America Corp Warranty
Procedure Manual)
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3. Weichai America Corp.
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Table of Contents
1 Disassembly & Assembly of Engine.....................................................................................5
1.1 Safety Precautions............................................................................................................5
1.2 Environmental Protection Measures .................................................................................5
1.3 Notes for Disassembly and Assembly of Engine...............................................................5
2 Engine Block Group.............................................................................................................6
2.1 Disassembly and Assembly of Engine Block Group..........................................................6
2.2 Reassembly, Disassembly and Assembly of Cylinder Block .............................................9
2.3 Disassembly and Assembly of Gear Chamber................................................................11
2.4 Disassembly and Assembly of Front-end Cover .............................................................14
2.5 Disassembly and Assembly of Piston Nozzle..................................................................15
2.6 Disassembly and Assembly of Thrust Plate ....................................................................16
2.7 Disassembly and Assembly of Front and Rear Oil Seals ................................................18
2.8 Disassembly and Assembly of Flywheel Housing ...........................................................19
2.9 Disassembly and Assembly of Cylinder Head.................................................................22
2.10 Disassembly and Assembly of Cylinder Head Cover ............................................29
2.11 Disassembly, Overhaul and Assembly of Hoisting Rings of Engine ......................30
2.12 Disassembly and Assembly of Oil-gas Separator .................................................31
3 Crank-Connecting Rod Mechanism ...................................................................................34
3.1 Disassembly and assembly of crankshaft .......................................................................34
3.2 Disassembly and assembly of piston & connecting rod group.........................................37
3.3 Disassembly and assembly of crankshaft bearing...........................................................41
3.4 Disassembly and assembly of flywheel and ring gear .....................................................42
3.5 Disassembly and assembly of vibration damper and crankshaft pulley...........................44
4 Valve train..........................................................................................................................45
4.1 Disassembly and assembly of valve train .......................................................................45
4.2 Disassembly and assembly of camshaft and camshaft timing gear.................................47
4.3 Disassembly and assembly of rocker arm and rocker shaft ............................................50
4.4 Disassembly and assembly of tappet and push rod ........................................................52
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4.5 Disassembly and assembly of valve ...............................................................................54
4.6 Disassembly and assembly of intermediate gear ............................................................57
5 Intake/exhaust system .......................................................................................................59
5.1 Disassembly and assembly of intermediate gear ............................................................59
5.2 Disassembly and Assembly of Turbocharger System .....................................................60
5.3 Disassembly and assembly of exhaust manifold.............................................................62
5.4 Disassembly and Assembly of Mix Air Intake Pipe..........................................................64
5.5 Disassembly and assembly of intake manifold................................................................66
6 Ignition System ..................................................................................................................68
6.1 Ignition System Assembly and Disassembly...................................................................68
6.2 Engine Control Unit (ECU) Assembly and Disassembly..................................................70
6.3 Signal Generator Assembly and Disassembly ................................................................71
7 Fuel System.......................................................................................................................73
7.1 LPG Intake System Assembly and Disassembly.............................................................73
7.2 Mix air Intake System Assembly and Disassembly .........................................................74
7.3 NG Gas Supply And Gas Flow Control Valve (EPR Valve) Assembly And Disassembly.76
8 Cooling System..................................................................................................................77
8.1 Cooling System Disassembly and Assembly ..................................................................77
8.2 Radiator Disassembly and Assembly..............................................................................78
8.3 Fan and Hub Disassembly and Assembly.......................................................................79
8.4 Water Pump and Water Pump Disassembly and Assembly ............................................80
8.5 Water Pump Disassembly and Assembly .......................................................................82
8.6 Disassembly and Assembly of Thermostat .....................................................................83
9 Lubrication System ............................................................................................................86
9.1 Disassembly and Assembly of Lubrication system..........................................................86
9.2 Disassembly and Assembly of Oil Sump.........................................................................88
9.3 Disassembly and assembly of oil strainer .......................................................................90
9.4 Disassembly and assembly of oil pump intermediate gear assembly..............................91
9.5 Disassembly and assembly of oil pump ..........................................................................92
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9.6 Disassembly and assembly of main oil passage pressure limiting valve .........................94
9.7 Disassembly and assembly of oil filter ............................................................................95
9.8 Disassembly and Assembly of Oil Cooler Cover .............................................................96
9.9 Disassembly and Assembly of Oil Cooler .......................................................................98
9.10 Disassembly and Assembly of Oil Cooler Bypass Valve .......................................99
10 Start-up System..................................................................................................101
10.1 Disassembly and Assembly of Start-up System..................................................101
11 Engine Accessory System ..................................................................................102
11.1 Engine Accessory System Assembly and Disassembly ......................................102
11.2 Alternator Assembly and Disassembly................................................................103
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6. Weichai America Corp.
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1 Disassembly & Assembly of Engine
1.1 Safety Precautions
Please strictly comply with instructions in this manual to safely and properly disassemble and
assemble the engine.
1.2 Environmental Protection Measures
Please comply with relevant laws and regulations on environmental protection when handling oil
and hydrocarbon waste. For further instructions please contact your local officials.
1.3 Notes for Disassembly and Assembly of Engine
Failure in complying with safety regulations and basic safety practices causes the majority of
engine-related accidents. Proper training is required for all engine operators and maintenance
personnel. Any violation of instructions in this manual may result in serious injury or death.
Note: Before proceeding with any maintenance or repair operation, place a sign clearly
stating “Maintenance in Progress, Do Not Use” on the engine starter switch.
Take the following precautions before using a lockout tool and beginning maintenance or repair:
• Ensure the maintenance site and surrounding area is clean and suitable for safe operation.
• Remove any rings, necklaces, watches, or other jewelry and wear appropriate close-fit work
clothes before entering the maintenance site.
• Wear relevant protective devices (goggles, gloves, shoes, masks, work clothes, helmet, etc.)
that are in good condition prior to entering the maintenance site.
• Do not use any defective, worn, broken, or inappropriate tools.
NOTICE: THE ENGINE MUST BE COMPLETELY SHUT DOWN PRIOR TO
MAINTENANCE.
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7. Weichai America Corp.
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2 Engine Block Group
2.1 Disassembly and Assembly of Engine Block Group
2.1.1 Explosive View of Engine Block Group
Fig. 1 Exploded view of engine block assembly
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Fig. 2 Exploded view of engine block assembly
Fig. 2- 1 Exploded view of engine block assembly
No. name No. name No. name
1 Spring pin 7 washer 13 Hexagon bolt
2 Rivet 8
Hexagon socket
head bolt
14 Knock sensor
3 O-ring 9 Cylinder liner 15 Seal washer
4 Hexagon head plug 10
Main oil passage
rear screw plug
16 Hexagon plug
5 Cylindrical pin 11 Seal washer 17 Hexagon plug
6 Oil press sensor 12 Rivet
2.1.2 Pre-assembly Preparation
1. Equipment condition: socket wrench, copper hammer
2. Preparation: disassemble the transmission and clutch; disassemble the flywheel, flywheel
housing, gear housing and oil pan.
2.1.3 Disassembly steps of engine block group
1. Remove main oil passage screw plug;
2. Remove cylinder liner;
3. Unscrew the crankcase fastening bolts;
4. Unscrew the main bearing bolt;
5. Remove sealing ring.
2.1.4 Assembling Steps of Engine Block Group
The assembly should be conducted in the reverse order of disassembly.
2.1.5 Inspection and repair of engine block group
Key point 1:
Assembly
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9. Weichai America Corp.
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Tightening
torque
22Nm~29Nm
Grade
8.8
Tightening
torque
29Nm~35Nm
Grade
10.9
Key point 2:
Assembly
Tighten the main bearing bolts in a symmetric way according to the sequence shown in the figure
below. Before assembly, apply clean lubricating oil to the bearing surface of crankcase and the
threads of main bearing bolts. The main bearing bolts can be used repeatedly 6 times, the length
of the bolt extension is less than 172 mm.
Ⅰ
Ⅱ
Ⅲ
Ⅳ
Ⅴ
Ⅵ
Ⅶ
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Fig. 2-2 Tighten order of main bearing bolts
Tightening
torque
265Nm±25Nm
Key point 3:
Assembly
Tighten the cylinder head auxiliary bolts according to the sequence shown in the figure below,
and these bolts can be reused at most 2 times.
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10. Weichai America Corp.
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Ⅵ Ⅴ Ⅳ Ⅲ Ⅱ Ⅰ
16
17
18
10
11
12
3
4
5
2
1
6
9
8
7
15
14
13
21
20
19
Fig. 2-3 Cylinder Head Auxiliary Bolts Tightening Order
Key point 4:
Assembly
Before assembly, inspect the cylinder liner carefully for cracks and other defects, then clean and
press it into the cylinder bore with special tool after applying molybdenum powder to the outside
surface of cylinder liner.
2.2 Reassembly, Disassembly and Assembly of Cylinder Block
2.2.1 Explosive View of Preassembly of Cylinder Block
Figure 2-4 Explosive View of Preassembly of Cylinder Block
No. name No. name No. name
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1 Cylinder block 5 Bowl plug 9 Bowl plug
2 Crankcase 6 Bowl plug 10 Camshaft bush
3 Bowl plug 7 Bowl plug
11 Cylindrical pin with
internal thread
4 Bowl plug 8 Bowl plug 12 Main bearing bolt
2.2.2 Pre-assembly Preparation
1. Equipment condition: socket wrench, copper hammer
2. Preparation: disassemble the transmission and clutch; disassemble the flywheel, flywheel
housing, gear housing and oil pan.
2.2.3 Disassembling Steps of Preassembly of Cylinder Block
1. Disassemble the camshaft bushing;
2. Disassemble the main bearing bolts and crankcase fastening bolts;
3. Disassemble the crankcase;
4. Disassemble the cylinder pin with internal threads;
2.2.4 Assembling Steps of Preassembly of Cylinder Block
The assembly should be conducted in the reverse order of disassembly.
2.2.5 Overhaul of Preassembly of Cylinder Block
Key point 1:
For disassembling, use special tooling to disassemble the camshaft bushing. In the process of
disassembly, take care to protect other bushings.
Key point 2:
Before assembly, carefully check if there is scratch on internal surface of camshaft bushing, and
replace it when necessary. The camshaft bushing oil hole should be aligned with the camshaft
bottom hole oil hole of engine block.
Key point 3:
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Before assembly, clean the upper plane of crankcase and it is necessary to apply sealants onto the
upper plane of crankcase.
Key point 4:
If replace the bowl, clean the bottom hole and bowl surface before assembly,
Apply sealant to the joint face of the bowl and engine body. Press into the bowl plug with special
tool when assembling, press the depth down to (0~1) mm under pressure, and the height
difference of the end face of the bowl is not greater than 0.5mm.
2.3 Disassembly and Assembly of Gear Chamber
2.3.1 Explosive View of Gear Chamber
Figure 2-5 Explosive View of Gear Chamber
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No. name No. name No. name
1 Seal ring 4 Hexagon bolt 7 Hexagon bolt
2 O-ring 5 O-ring 8 Hexagon plug screw
3 Cylinder pin 6
Hexagon plug
screw
9 Timing gear
chamber
2.3.2 Pre-assembly Preparation
1. Equipment condition: socket wrench
2. Preparation: disassemble the accessory of the gear chamber
2.3.3 Disassembling Steps of Gear Chamber
1. Disassemble the gear chamber fastening bolt
2. Disassemble the screw plug and composite washer;
3. Disassemble the gear chamber
4. Disassemble the seal ring
2.3.4 Assembling Steps of Gear Chamber
The gear chamber should be assembled in the reverse order of disassembly.
2.3.5 Overhaul of Gear Chamber
Key point 1:
Symmetrically and crosswise tighten up the gear chamber fastening bolts in the order shown in
the figure below.
Tightening torque 44～58N.m
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14. Weichai America Corp.
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Figure 2-6 Schematic Diagram of Fastening Order of Gear Chamber Fastening Bolts
Key point 2:
Before assembly of the seal ring, observe if there is scratch or other defects on the seal ring; if
there is, timely replace it with a seal ring. For assembling, apply oil onto the seal ring, completely
press it into groove, and avoid scratching the seal ring by groove.
Key point 3:
For disassembling the gear chamber, first dismantle the gear chamber fastening bolts, and then
disassemble the intermediate gear shaft and oil pump intermediate gear shaft. After disassembly
of gear chamber, put it in a clean environment.
Key point 4:
First, after installing the intermediate gear shaft into the intermediate gear, put the intermediate
gear into the gear chamber; apply sealant at water inlet and outlet ports of cylinder block and
press in seal rings.
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2.4 Disassembly and Assembly of Front-end Cover
2.4.1 Explosive View of Front-end Cover
Figure 2-7 Explosive View of Front-end Cover
No. name No. name No. name
1 Seal ring 3 Hexagon bolt 5 Hexagon bolt
2 O-ring 4 O-ring 6 Hexagon plug screw
2.4.2 Pre-assembly Preparation
1. Equipment condition: socket wrench
2. Preparation: disassemble the accessory of the gear chamber
2.4.3 Disassembling Steps of Front-end Cover
1. Disassemble the front-end cover fastening bolt;
2. Disassemble the front-end cover;
3. Disassemble the front-end cover gasket.
2.4.4 Assembling Steps of Front-end Cover
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The assembly should be conducted in the reverse order of disassembly.
2.4.5 Overhaul of Front-end Cover
1. After disassembling the front end cover, put it in a clean environment, before assembly, check
if there is relatively big dirt inside the front end cover to ensure the cleanliness of front end
cover.
2. Before assembly of front end cover, apply the sealant at junction surface of engine block, and
the thread of sealant should be continuous.
3. Check if the gasket is damaged; if it is damaged, it is necessary to replace it with a new one.
For assembling, press the gasket completely into the front end cover groove.
2.5 Disassembly and Assembly of Piston Nozzle
2.5.1 Explosive View of Piston Nozzle
Figure 2-8 Explosive View of Piston Nozzle
No. name No. name No. name
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17. Weichai America Corp.
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1
Piston nozzle
assembly
3 Elastic cylinder pin
5
2 Nozzle 4 Hollow bolt 6
2.4.2 Pre-assembly Preparation
1. Equipment condition: socket wrench
2. Preparation: disassemble the crankshaft and crankcase.
2.4.3 Disassembling Steps of Piston Nozzle
1. Disassemble the hollow bolt;
2. Disassemble the nozzle assembly;
3. Disassemble the elastic cylinder pin.
2.4.4 Assembling Steps of Piston Nozzle
The piston cooling nozzle should be assembled in the reverse order of disassembly.
2.4.5 Overhaul of Piston Nozzle
Key point 1:
Assembly
Tightening torque of hollow bolt:
Tightening
torque
20～30N.m
Key point 2:
Assembly
Check if the positioning cylinder pin is defective, and replace it when necessary. Align the
positioning cylinder pin with cylinder pin hole of engine block, use a copper hammer to knock
lightly the nozzle body to make the cylinder pin completely enter into engine block cylinder pin
hole.
2.6 Disassembly and Assembly of Thrust Plate
2.6.1 Explosive View of Thrust Plate
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Figure 2-9 Explosive View of Thrust Plate
No. name No. name
1 Upper thrust plate 2 Lower thrust plate
2.6.2 Pre-assembly Preparation
1. Equipment condition: socket wrench
2. Preparation: disassemble the crankshaft and crankcase.
2.6.3 Disassembling Steps of Thrust Plate
1. Disassemble the crankcase;
2. Disassemble the crankshaft;
3. Disassemble the thrust plate.
2.6.4 Assembling Steps of Thrust Plate
1. Assemble the crankshaft;
2. Assemble the upper thrust plate (no ear);
3. Assemble the lower thrust plate.
2.6.5 Overhaul of Thrust Plate
The thrust plates should be used in pairs. For assembling, first install crankshaft into the engine
block, install the upper thrust plate (no ear), apply lubricating grease onto the lower thrust plate,
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19. Weichai America Corp.
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attach it to the crankcase and assemble it together with crankcase. The oil groove side of thrust
plate should be outward.
2.7 Disassembly and Assembly of Front and Rear Oil Seals
2.7.1 Explosive View of Front and Rear Oil Seals
Figure 2-10 Explosive View of Front and Rear Oil Seals
No. name No. name
1 Rear oil seal 2 Front oil seal
2.7.2 Pre-assembly Preparation
1. Equipment condition: socket wrench
2. Preparation: disassemble the crankcase and flywheel housing.
2.7.3 Disassembling Steps of Front and Rear Oil Seals
1. Disassemble the gear chamber;
2. Disassemble front oil seal;
3. Disassemble the crankcase;
4. Disassemble the rear oil seal.
2.7.4 Assembling Steps of Front and Rear Oil Seals
The front and rear oil seals should be assembled in the reverse order of disassembly.
2.7.5 Overhaul of Front and Rear Oil Seals
1. Before assembly of oil seals, the installation hole and oil seals should be cleaned, free of dirt.
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20. Weichai America Corp.
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For assembling oil seals, use special tooling to steadily press into the oil seals. Before
assembly, the lubricant should be applied to oil seals and pressing tooling.
2. The oil seal should not be reused after disassembly.
2.8 Disassembly and Assembly of Flywheel Housing
2.8.1 Explosive View of Flywheel Housing
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Figure 2-11: Explosive View of Flywheel Housing
No. name No. name No. name
1 Flywheel housing 7 Speed sensor
13 Observation hole
cover plate
2
Flywheel housing
bolt
8 Hexagon plug
14 Hexagon bolt
3 Flywheel 9 Seal washer
15 Flywheel Housing
Coupling Ring
4 Starter 10 Cylinder pin 16 washer
5 stud 11
Observation hole
cover plate
17 Hexagon bolt
6 nut 12 Hexagon bolt
2.8.2 Pre-assembly Preparation
1. Equipment condition: socket wrench, copper hammer
2. Preparation: disassemble the transmission and clutch; disassemble the flywheel.
2.8.3 Disassembling Steps of Flywheel Housing
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22. Weichai America Corp.
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1. Disassemble the flywheel housing bolts;
2. Disassemble the flywheel housing hexagon bolts and inspection port cover plate;
3. Disassemble the flywheel housing.
2.8.4 Assembling Steps of Flywheel Housing
1. Apply some sealant around the oil cavity.
2. Assemble the flywheel housing into the engine block.
3. Fasten the flywheel housing bolts.
4. Assemble the starter into the flywheel housing and fasten the bolt.
2.8.5 Inspection and repair of flywheel housing
1. Symmetrically tighten up the flywheel housing bolts in the order shown in the figure below.
Before assembly, apply oil to the bolt flange face. Each flywheel housing bolt can be
repeatedly used twice.
Figure 2-12 Fastening Order of Flywheel Housing Bolt
2. Apply sealant onto the junction surface of cylinder block and flywheel housing, and strictly
prevent bump during hoisting the flywheel housing.
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2.9 Disassembly and Assembly of Cylinder Head
2.9.1 Explosive View of Cylinder Head
Figure 2-13 Explosive View of Cylinder Head
No. name No. name No. name
1 O seal ring 5
Ignition winding
clamp plate
9 Cylinder head
gasket
2 Clump block 6
Ignition winding
bush
10 Secondary Blots
3 Valve stem seal 7 Shoulder nut
4
Cylinder head main
bolt
8 Cylinder head
2.9.2 Disassembling Steps of Cylinder Head
1. Remove the two ring bolts.
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24. Weichai America Corp.
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2. Loosen cylinder head auxiliary bolt nuts, and take down the clamping block;
3. Loosen cylinder head main bolts; place them on the appropriate place.
4. loosen the install bolt of the Ignition winding clamp plate, remove the Ignition winding bush
and remove the O seal ring;
5. After disassembling cylinder head, put it on a paperboard to avoid wear of the upper surface
of combustion chamber and its sealing surface. If a multiple of cylinder heads are
disassembled, it is necessary to mark the cylinder number on the cylinder head in order to
analyze the problems;
6. Disassemble the cylinder head gasket. If a multiple of cylinder head gaskets are disassembled,
it is necessary to mark the cylinder number on the cylinder head gasket in order to analyze the
problems;
7. If the cylinder head auxiliary bolts were needed to be replaced or checked, remove the
cylinder head auxiliary bolts;
8. Remove valve train including rocker arm support, intake valve, exhaust valve etc. (refer to
"Disassembly of valve mechanism");
9. If the valve stem sealing sleeve were needed to be replaced, remove the valve stem sealing
sleeve by using special tooling or clamping the outer flank of valve stem sealing sleeve with
pliers to rotate and lift up. Once the valve stem sealing sleeve is removed, it will be useless
and cannot be reused.
2.9.3 Assembling Steps of Cylinder Head
1. Assemble cylinder head auxiliary bolt, there are three types of cylinder heads.
1) It is allowed that the cylinder head auxiliary bolt can be reused for two times, after that,
please renew them;
2) Apply anaerobic thread-locking sealant 262 to the screw-in end (the end with shorter thread)
of cylinder head auxiliary bolts in the first row at the side of oil cooler cover assembly, and
apply sealant to the remaining auxiliary bolts;
3) Clean the thread holes on cylinder block;
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25. Weichai America Corp.
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4) Tighten the bolts to (76~102) Name.
2. Assemble cylinder head gasket
Fig. 2-14 Cylinder head gasket
1) The cylinder head gasket can only be used for once and must be replaced with a new one
when repairing;
2) Clean and apply fresh lubricating oil to the inner wall of cylinder liner, clean the engine
block upper surface, and then place the cylinder head gasket in accordance with the
corresponding pin holes properly;
3) Check whether the holes on cylinder head gasket are aligned with those on cylinder block,
and whether the cylinder head gasket is assembled properly.
3. Assemble valve stem sealing sleeve
1) All valve stem sealing sleeve can only be used for once and must be replaced with a new one
after removal;
2) Check the valve stem sealing sleeve and spring for defects;
3) Install the valve stem sealing sleeve to valve guide;
4) Apply lubricating oil to the lip edge of valve stem sealing sleeve;
5) Mount the valve stem sealing sleeve by using special tool and rubber hammer.
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26. Weichai America Corp.
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Fig. 2-15 Assembly of valve stem sealing sleeve
4. Assemble cylinder head
1) Clean the cylinder head carefully and ensure it is free of dust, chip, sand and other dirt; after
that, clean the cylinder head lower surface;
2) Check cylinder head intake duct, water channel and cylinder for foreign matters, and the
cylinder head gasket and cylinder head lower surface should clean;
3) Position the cylinder head by using pin-side method before tightening the cylinder head
bolts;
4) Assemble the cylinder head.
5. Assemble clamping block
1) Clean the clamping block;
2) Apply clean lubricating oil to the bearing surface of clamping block before assemble the
clamps to cylinder heads in turn, and note that the oil quantity should be appropriate without
flowing to the gap between cylinder heads;
3) When assembling, the direction of clamping block groove should be the same with that of the
gap between cylinder heads;
4) Screw the cylinder head auxiliary bolt nuts onto the bolts manually.
6. Assemble cylinder head bolt
Valve
Guide
Install tool
Valve Stem Seal
cylinder head
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27. Weichai America Corp.
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1) It is allowed that the cylinder head main bolt can be reused for three times;
2) Align the cylinder heads in turn, and apply a proper amount of clean lubricating oil to
cylinder head main bolt thread, flange bearing surface and flanged nut before installing them
to cylinder head.
3) Tighten the cylinder head main bolts and cylinder head auxiliary bolt nuts to (30~50)Nm
with torque wrench;
4) Knock the clamping blocks to ensure they are all seated in place;
5) Tighten the auxiliary nuts to 100Nm in turn with torque wrench, and make marks on the nuts;
6) Tighten the main bolts to 200Nm in turn with torque wrench, and make marks on the bolts;
7) Rotate the auxiliary bolt nuts by 90° in turn with torque wrench, and mark the new positions
of the nuts;
8) Rotate the main bolts by 90° in turn with torque wrench, and mark the new positions;
9) Rotate the auxiliary bolt nuts by 90° in turn again with torque wrench to (120~160)Nm;
10) Rotate the main bolts by 90° in turn again with torque wrench to (240~340) Nm.
Tighten the cylinder head bolts according to the sequence shown in the figure below, The number
1-21 is the secondary bolt, the number 22-45 is the main bolt,
Fig. 2-16 Cylinder Head Bolts Tightening Order
7. Assemble ignition winding bush
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Apply some sealant on the O- ring, put it in the groove of the cylinder head O seal ring. Assemble
the ignition winding clamp plate, fasten the bolt in a symmetric way. Tighten the bolt to 15 Nm
firstly, then tighten the bolt to (20-25) Nm.
2.9.4 Inspection and repair of cylinder head
1. Inspect the joint between cylinder head and engine block for water, oil and air/gas leakage and
other abnormal phenomenon before removing cylinder head. If any, renew the cylinder head
gasket and check again; the disassembly method of cylinder head gasket can be found in this
Section.
2. Inspect the surface of cylinder head carefully for color change and crack; if any crack is found,
dye penetrant inspection must be carried out.
3. Before removing valve train, inspect the valve sinkage by using a depth micrometer, i.e. the
vertical distance between valve bottom surface and cylinder head bottom surface, and the
difference between the measured sinkage and the required sinkage can reflect indirectly the
wear of valve and valve seat. As shown in figure 2-17.
Fig. 2-17 Depth micrometer
See table 4-3 for the required valve sinkage; if the valve sinkage exceeds the permissible
range, it may be necessary to check the wear of the valve and valve seat by installing a new
valve to measure the valve sinkage again; after these operations, if the valve sinkage is still
greater than the required, please replace the cylinder head to ensure the reliability of the diesel
engine. If the valve sinkage does not exceed the permissible value, please remove the valve to
check the sealing surfaces of valve and valve retainer for obvious wear and abnormal damage.
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Table 2-3 Required valve sinkage
Required valve sinkage (mm)
Intake valve -0.2~0.2
Exhaust valve -0.22~0.22
4. Check the inside of cylinder head intake and exhaust passages for water leakage after
removing valve train; if any, please clean the intake and exhaust passages and perform dye
penetrant inspection to confirm the faulty location, and renew the cylinder head when
necessary.
5. Clean cylinder head, particularly the combustion chamber surface, valve seat, intake/exhaust
valve, intake/exhaust passage, so as to remove the soot deposition and adhesive from the
surface, and check the surface condition.
6. Check valve guide inside diameter, if it exceeds the permissible value due to wear, the guiding
function of the valve could be affected and thus reducing the operational reliability of diesel
engine. The valve guide inside diameter can be measured with inside micrometer, as shown in
figure 4-18. Permissible inside diameter is （9.0~9.015） mm; if this range is exceeded,
please replace the cylinder head to ensure the operational reliability of the diesel engine.
Fig. 2-18 Inside micrometer
7. Remove cylinder head gasket and check it for visible damages; if any, find the causes. What
should be pointed out is that no matter whether the cylinder head gasket is failure or not,
please replace with new one as long as it was removed.
8. Before removal, check the rubber lip of valve stem sealing sleeve for damage, spring for
failure and other abnormalities, but it should be noted that once the valve stem sealing sleeve
is removed, a new one should be replaced.
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2.10 Disassembly and Assembly of Cylinder Head Cover
2.10.1 Explosive View of Cylinder Head Cover
Figure 2-19 Explosive View of Cylinder Head Cover
No. name No. name No. name
1 Hexagon bolt 4 O-ring 7 Supporting block
2
Inner Hexagon
Socket Head Cap
Screw
5
Cylinder head
cover
8 Wave spiral washer
3 Cover 6
Cylinder head
cover gasket
2.10.2 Disassembling Steps of Cylinder Head Cover
1. Loosen the install bolt, remove the O-ring and the cover.
2. Loosen the bolt of the cylinder head cover, remove the cover and the washer.
3. Take out the cylinder head covers and cylinder head cover gaskets upwards vertically.
2.10.3 Assembly steps of cylinder head cover
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1. Check the new cylinder head cover gasket for manufacturing and operational defects as well
as other damages before installing.
2. Clean the cylinder head upper surface, and then correctly install the cylinder head gaskets in
turn.
3. Clean the cylinder head covers, and correctly install them onto the cylinder heads in turn.
4. Install cylinder head cover bolts and tighten them. Tightening torque: (10-15) Nm.
5. Put the O-ring into the groove, assemble the cover.
2.10.4 Inspection and repair of cylinder head cover
Key point 1:
Assembly
The cylinder head cover gasket can only be used for once and should be replaced when repairing.
Key point 2:
Inspection
1) Check if there is crack, large wearing and any other damage of cylinder head cover itself. If
there is crack, it is necessary to replace it with a new cylinder head cover.
2) If there is oil leakage at cylinder head cover gasket, it is necessary to check the failure of
cylinder head gasket and wearing degree of upper plane of cylinder head and lower plane
sealing surface of cylinder head cover. If there is leakage, it is necessary to replace it with a
new cylinder head cover gasket, and check again if there is still oil leakage.
2.11 Disassembly, Overhaul and Assembly of Hoisting Rings of Engine
2.11.1 Explosive View of Hoisting Rings of Engine
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Figure 2-20 Explosive View of Hoisting Rings of Engine
No. name No. name
1
Engine Hanger
Plate
3 Hexagon bolt
2
Bracket of oil-gas
separator
4 Bracket
2.11.2 Disassembling Steps of Hoisting Rings of Engine
Loosen the engine Hanger Plate, bracket of oil-gas separator and the hexagon bolt, remove them.
2.11.3 Assembling Steps of Hoisting Rings of Engine
Remove and check front and rear lifting eyes and clamping blocks for crack, heavy deformation
and other failures, and check the hexagon head bolts. If any failure is found, please replace with
new parts.
2.12 Disassembly and Assembly of Oil-gas Separator
2.12.1 Explosive View of Oil-gas Separator
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Figure 2-21 Explosive View of Oil-air Separator
No. name No. name No. name
1 Oil-gas separator 6 Pipe
11 Air intake pipe of
oil-gas separator
2 Joint 7 Hollow screw 12 Pipe clamp
3
Oil return pipe of
oil-gas separator
8
Air intake pipe of
oil-gas separator
13 Air exhaust pipe of
oil-gas separator
4 Pipe joint 9 Washer 14 Pipe joint
5 Washer 10 Pipe joint 15 Washer
2.12.2Disassembly steps of oil-gas separator
1. Unscrew the two fastening bolts from the oil-gas separator intake pipe joint on cylinder block;
2. Unscrew the bolt fixing the oil-gas separator to front lifting eye;
3. Remove the pipe clips and clamps of the oil-gas separator gas outlet pipe, oil return pipe and
the oil pan oil return pipe;
4. If the connecting pipe at the end of oil-gas separator oil return pipe is needed to be removed
and checked, loosen the bushing and take out the connecting pipe.
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5. If further disassembly is required, the oil-gas separator assembly can be removed as shown in
figure 2-21.
2.12.3 Assembly steps of oil-gas separator
The oil-air separator should be assembled in the reverse order of disassembly. It is required to
ensure correct positions of all rubber tube and connectors according to Figure 2-21. At the same
time, take care to ensure the turning angle of rubber tube during assembly and fixing position can
match with the engine.
2.12.5 Inspection and repair of oil-gas separator
1. Check each component surface for damage, crack, rubber hose hardening and other failures; if
any of the aforesaid problems is found, please renew the corresponding part;
2. To check the oil-gas separator for blockage, you can charge the air inlet pipe of oil-gas
separator to see whether the air flow is smooth; if not, please supply pressurized air to every
pipe port of oil-gas separator to remove the impurities and oil fouling from the oil-gas
separator. After completing above operations, if the oil-gas separator is still blocked, please
renew it.
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3 Crank-Connecting Rod Mechanism
3.1 Disassembly and assembly of crankshaft
3.1.1 Exploded view of crankshaft assembly
Figure 3-1 Explosive View of Crank-Connecting Rod Mechanism
No. name No. name No. name
1 Main bearing bolt 6 Absorber 11 Flywheel bolt
2 Crankcase 7 Crankshaft pulley 12 Flywheel
3
Connecting Rod
Cover
8 Bolt
13 Flywheel Ring Gear
4 Crankshaft 9 Piston and
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connecting rod
5 Main bearing shell 10 Engine block
3.1.2 Pre-assembly Preparation
1. Equipment condition: socket wrench, torque wrench, open spanner, hole ring pliers
2. Preparation: attach the engine body to the rotating bracket, disassemble the cylinder head, oil
pan and other peripheral parts.
3.1.3 Disassembling Steps of Crank-Connecting Rod Mechanism
1. With the engine crankcase upward, remove the main bearing bolts, and place them in order.
2. Remove the crankshaft, flywheel and then the front/rear thrust washers and the bearing at
flywheel end. Take out the oil seal; place the crankshaft on the carrier (the crankshaft should
be vertically placed in case of long-time preservation).
3. Place the removed parts as required.
3.1.4 Assembling Steps of Crank-Connecting Rod Mechanism
The assembly should be conducted in the reverse order of disassembly.
1. Clean the main bearing bottom holes on cylinder block.
2. Press the upper bearing into the bottom hole of the cylinder block, and wipe away the foreign
matters scraped from the bearing port.
1) The upper bearing should be checked for scratches strictly before press-fitting, and the
scratched one should not be reused.
2) The upper bearing bush should be aligned with the oil hole and oil groove on the cylinder
block after installation, and any deviation above 1/5-1/4 of the oil hole is not allowed; the
upper bearing should fit well with the main bearing bottom hole on the cylinder block.
3. Apply appropriate clean lubricating oil to the inside of main bearing.
4. Wipe the oil off the lower surface of engine block.
5. Apply sealant evenly on the lower surface of engine body with rubber roller.
6. Lift the crankshaft, blow the oil duct hole with compressed air, wipe the main bearing journal
and connecting rod journal with a towel, and place them into the cylinder block gently,
preventing the crankshaft from being scratched.
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7. Clean the upper thrust washer, and press it into the cylinder block, always with the oil groove
of upper thrust washer outwards (towards the crankshaft).
8. With the oil seal flat/not distorted, place the oil seal into the seal ring groove on the lower
plane of cylinder block with a special tool.
9. Press lower main bearing bush and lower thrust washer into the crankcase (with the oil groove
towards the crankshaft), assemble crankcase.
10. Apply clean lubricating oil to the thread bearing face of crankcase and the threads of main
bearing bolt, install the main bearing bolts without tightening, and then tighten all main
bearing bolts in the sequence as shown in Fig. 3-2.
Fig 3- 2 Tightening sequence of main bearing bolts
11. Tighten the main bearing bolts by using low torque pneumatic wrench for the first time, then
tighten to 80Nm for the second time, and 250Nm ~280Nm for the third. Crankshaft
assembling is completed.
3.1.5 Inspection and repair of crankshaft
1. Check rounded corners of the main bearing journal and connecting rod journal, the contacting
part of crankshaft and bearing for cracks, and clean the oil passage.
2. Check the main bearing journal and connecting rod journal for wear, visible linear traces,
metal flake and cracks.
3. Check the wear condition of front/rear oil seals.
4. Check the main bearing bolts for thread damage or other failures.
5. Check the front and rear threaded holes of crankshaft flange for cracks.
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6. Check the wear of main journal and bending and distortion condition of crankshaft
3.2 Disassembly and assembly of piston & connecting rod group
3.2.1 Exploded view of piston & connecting rod group
Fig 3-3 Exploded view of piston & connecting rod assembly
No. name No. name No. name
1 Piston 5
Connecting rod
bolt
9 Circlip
2 Piston pin 6 Taper-sided ring
10 Connecting rod
bushing
3
Connecting rod
body
7 Conical ring
11 Connecting Rod
Upper Shell
4
Connecting rod
cover
8 Oil ring
12 Connecting Rod
Lower Shell
3.2.2 Pre-assembly Preparation
1. Equipment condition: socket wrench, torque wrench, wooden hammer, hole ring pliers
2. Preparation: remove the connecting rod cover.
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3.2.3 Disassembly steps of piston & connecting rod assembly
1. Inspections before disassembling. Check the axial clearance of connecting rod and the
tightening torque of connecting rod bolts.
2. Place the engine obliquely and laterally, crank the engine to position bring the piston to be
removed to BDC, and remove the connecting rod bolt and big end cap;
3. Crank to TDC, knock out the piston with a wood hammer carefully, protecting the big end
from being blocked by cylinder block.
4. Remove the remaining pistons following the same method, and place them in order.
5. Use a circlip pliers to remove the circlip on both sides of piston carefully, push out the piston
pin and remove the connecting rod body. Number the piston pins and connecting rods
respectively, and place them in order.
6. Use a piston ring pliers to remove the 1st ring, 2nd ring and the oil ring, and mark them
respectively.
7. Remove connecting rod lower shell and upper shell, mark and place them in order.
3.2.4 Assembly steps of piston & connecting rod group
The connecting rod and the piston are in the same quality group, the connecting rod and
connecting cover must be matched.
1. Use a circlip pliers to install one circlip for hole into the piston circlip groove, and turn the
circlip for a secure installation, always with the angular face inwards, and the opening of
piston ring circlip upwards.
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Fig 3-4 Exploded view of Circlip
2. Insert the small end of connecting rod into the piston cavity, align the connecting rod small
end with the piston pin hole and install the piston pin; finally, install the piston pin circlip on
the other side. Pay attention that the oblique cut of connecting rod should be in reverse
direction with that of the inlet hole of piston cooling oil duct, and the connecting rod small end
hole and piston pin should be applied with appropriate clean lubricating oil before assembling.
Fig 3-5 Exploded view of piston and connecting rod
3. Arrange the preassembled piston & connecting rod assemblies in order according to the
cylinder number, and use a piston ring pliers to install the oil ring, 2nd gas ring and 1st gas
30°
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ring into the piston ring grooves in sequence, ensuring that the piston ring face with "TOP"
upwards, and the ring could be moved flexibly in the ring groove.
Note: Mark the pistons with G1,G2,G3,G4,G5 according to their weights, when being
installed in the same engine, pistons of same weight group shouldn’t be miss installed.
4. Wipe the cylinder inner wall, crank arm and piston & connecting rod assembly, and apply
clean lubricating oil to the joints of moving parts.
5. Adjust the opening positions of rings: the opening of 1st ring should be 30° away from the
piston pin centerline, the opening of 2nd ring should be 120° away from that of the 1st ring,
and the opening of oil ring should be 120° away from both openings of the 1st ring and 2nd
ring, as shown in fig. 5-5.
Fig 3-6 Schematic diagram for included angles between piston rings
6. Crank the engine to bring the No.1 cylinder and No.6 cylinder to BDC, install the piston &
connecting rod assemblies of No.1 cylinder and No.6 cylinder, and install the connecting rod
bolts without tightening, always with the parting surface of connection rod big end towards the
left side of cylinder block (i.e. the oil cooler side). Pay attention that the piston number should
be the same with the cylinder number, the connecting rod cap should be used in pair with the
connecting rod body, and the connecting rod bolt should be applied with clean lubricating oil
before installation.
1st
ring 2nd
ring
Piston pin in
horizontal direction
Oil ring
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7. Tighten the connecting rod bolts as follows: pretighten first, and next tighten diagonally with a
torque of 120 Nm, and finally turn them by 90°±5° to a torque of 170Nm~250 Nm. Complete
the installation for the other cylinders following the same method.
3.2.5 Inspection and repair of piston & connecting rod assembly
1. Check the rounded corner at the throat of combustion chamber and the piston pin seat for
cracks; check the skirt and head of piston for cylinder scuffing; check the piston pin hole for
excessive wear.
2. Check if the outer perimeter and the upper and lower end faces of the piston ring are
excessively worn.
3. Check if the oil ring is rotated flexibly in the piston oil groove.
4. Check if the outer perimeter of the piston ring is excessively worn.
5. Check the large end bottom hole, body and small end oil hole of connecting rod for cracks;
check the alloy layer of connecting rod for abnormal wear or metal flake; check the connecting
rod sides for abnormal wear, and check the connecting rod body for bending.
6. Check the connecting rod bushing for wear, and the alloy layer for discoloring, flake and
sliding etc.
3.3 Disassembly and assembly of crankshaft bearing
3.3.1 Exploded view of crankshaft bearing
Fig 3- 7 Exploded view of crankshaft bearing
No. name No. name No. name
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1 Crankshaft 2
Main bearing upper
shell
3 Main bearing lower
shell
3.3.2 Pre-assembly Preparation
1. Equipment condition: marker pen
2. Preparation: disassemble the pulley and flywheel group, remove the crankcase and crankshaft.
3.3.3 Disassembly steps of main bearing
Push the bearing out from its side by hand, and make a mark on the removed bearing
corresponding to the seat hole of engine block and crankcase.
3.3.4 Assembly steps of main bearing
1. Clean and wipe off the main bearing and mounting bottom hole.
2. If the bearings are not to be replaced with new ones, install them into the engine block (upper
half) and crankcase (lower half)with the reverse order disassembly, always with upper half and
lower half clearly distinguished, the former of which has oil groove; if the bearings are new,
install them directly. When installing, align the bearing lips and apply l lubricating oil.
3.3.4 Inspection and repair of main bearing
1. Clean the bearing bush and check its wear condition.
2. Check the bearing for metal flake, locating lip damage and horizontal cracks.
3.4 Disassembly and assembly of flywheel and ring gear
3.4.1 Exploded view of flywheel and ring gear
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Fig 3-8 Exploded view of flywheel and ring gear
No. name No. name No. name
1 Crankshaft 3 Flywheel ring gear 5 Bolt
2 Locating pin 4 Flywheel 6 Flywheel bolt
3.4.2 Disassembly steps of flywheel and ring gear
Disassemble the flywheel and ring gear with the reverse order of assembly.
3.4.3 Assembly steps of flywheel and ring gear
1. Bolt the flywheel ring gear together with the flywheel.
2. Knock a straight pin into the rear end of crankshaft always into position.
3. Insert a guide bar into the crankshaft threaded hole, install the flywheel, and pretighten
flywheel bolts diagonally.
Apply lubricating oil to the threads and bearing face of flywheel bolts.
Flywheel bolt specification: M14 (9 PCS)
4. Tighten the flywheel bolts
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Hand tightening specifications: After adding lubricating oil to flywheel bolt thread and bearing
surface, put the bolts into thread holes, and tighten them diagonally with a torque of 6020
0Nm. Afterwards, turn angle of 90°±5° for twice, and the torque reaches 230Nm~280Nm. If
the prescribed torque could not reach, replace the bolt with new one. The bolt could be used
for twice.
Auto-wrench tightening specifications: After adding lubricating oil to flywheel bolt thread and
bearing surface, put the bolts into thread holes, and tighten them diagonally with a torque of
60Nm. Afterwards, turn angle of 160°+5°, and the torque reaches 230Nm~300Nm. If the
prescribed torque couldn’t reach, replace the bolt with new one. The bolt could be used for
twice.
3.4.4 Inspection and repair of flywheel and ring gear
1. Check the flywheel bolts for thread damage or other failures.
2. Check the flywheel surface for crushing.
3. Check the flywheel ring gear for damage.
3.5 Disassembly and assembly of vibration damper and crankshaft pulley
3.5.1 Exploded view of vibration damper and crankshaft pulley
Fig 3- 9 Exploded view of vibration damper and crankshaft pulley
No. name No. name
1 Crankshaft 3 Pulley
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2 vibration damper 4 Bolt
3.5.2 Pre-assembly Preparation
1. Equipment condition: socket wrench, air wrench.
2. Preparation: remove the belt.
3.5.3 Disassembly steps of vibration damper and crankshaft pulley
Remove the pulley bolts, take down the pulley and vibration damper.
3.5.4 Assembly steps of vibration damper and crankshaft pulley
With the timing gear properly installed, install the vibration damper and pulley in sequence, and
tighten them onto the crankshaft flange with pulley bolt.
3.5.5 Inspection and repair of torsional damper and crankshaft pulley
1. Check the vibration damper for impact damage and deformation etc.
2. Check the pulley for damage, and the compressing point of bolt for crushing.
3. Check the pulley bolt for damage.
4 Valve train
4.1 Disassembly and assembly of valve train
4.1.1 Exploded view of valve train
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Fig. 4-1 Exploded view of valve train
No. name No. name No. name
1 Gear housing 8 Cylinder head 15 Valve bridge
2 Hexagon bolt 9 Tappet 16 Pin
3 Timing gear 10 Push rod 17 Rocker arm set
4 Hexagon bolt 11 Valve spring 18 Rocker arm shaft
5 Thrust plate 12 Exhaust valve 19 Hexagon bolt
6 Camshaft 13
Valve spring top
retainer
20 Rocker arm bracket
7 Intake valve 14 Valve collet 21
4.1.2 Disassembly steps of valve train
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1. Remove the rocker arm and the rocker shaft, and see section “Disassembly steps of rocker arm
and rocker shaft” for details;
2. Remove the intake/exhaust valve, and see section “Disassembly steps of valve” for details;
3. Remove the tappet and the push rod, and see section “Disassembly steps of tappet and push
rod” for details;
4. Remove the camshaft and the camshaft timing gear, and see section “Disassembly steps of
camshaft and camshaft timing gear” for details;
5. Remove the intermediate gear, and see section “Disassembly steps of intermediate gear” for
details.
4.1.3 Assembly steps of valve mechanism
1. Install the camshaft and the camshaft timing gear, and see section “Assembly steps of
camshaft and camshaft timing gear” for details;
2. Install the tappet and the push rod, and see section “Assembly steps of tappet and push rod”
for details;
3. Install the intake/exhaust valve, and see section “Assembly steps of intake/exhaust valve” for
details;
4. Install the rocker arm and the rocker shaft, and see section “Assembly steps of rocker arm and
rocker shaft” for details;
4.2 Disassembly and assembly of camshaft and camshaft timing gear
4.2.1 Exploded view of camshaft and camshaft timing gear assembly
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Fig.4-2 Exploded view of camshaft and timing gear assembly
No. name No. name No. name
1 Hexagon bolt 4 Thrust plate 7 Engine block
2
Camshaft timing
gear
5 Camshaft
3 Hexagon bolt 6 Gear housing
4.2.2 Pre-assembly Preparation
1. Equipment condition: dial indicator, torque wrench, towel, oil.
2. Preparation: remove the flywheel housing, remove the camshaft and timing gear.
4.2.3 Disassembly steps of camshaft and camshaft timing gear
1. Rotate the camshaft, and check if the camshaft and timing gear are flexible without being
blocked;
2. Use a dial indicator to check if there is any axial endplay for the camshaft compared with
previous conditions. Check the difference comparing with the axial clearance after assembling
(0.1mm~0.4mm);
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3. Check the backlash of timing gear;
4. On the engine assembly and disassembly work bench, rotate the crankshaft to locate the
camshaft timing gear at the TDC of the 1# cylinder. Unscrew the hexagon head bolts of
camshaft timing gear, and remove the timing gear and the locating pin;
5. Unscrew the hexagon head bolts of camshaft thrust plate, and remove the thrust plate;
6. Remove the camshaft.
4.2.4 Assembly steps of camshaft and camshaft timing gear
After removal, check the camshaft and timing gear; if any wear or larger deviation of other
parameters is found, repair the camshaft or replace with a new one.
1. Wipe the camshaft hole with a piece of towel, check the camshaft hole for scratches and apply
appropriate lubricating oil to the inner perimeter of camshaft bush with an oilcan. If any
impact damage is found on the camshaft hole, it is not allowed to repair it for reuse.
2. Insert the camshaft guide and camshaft sliding sleeve into the camshaft hole, wipe the
camshaft and check for impact damage; after this, insert the camshaft through the camshaft
hole, and when the camshaft is installed in place, remove the camshaft guide and camshaft
sliding sleeve. Be careful not to scratch the camshaft bush when inserting the camshaft.
3. Install the camshaft thrust plate, and mount and tighten the hexagon bolts applied with sealant.
Make sure the rocker arm rotates flexibly.
4. Polish the back of the cylinder body, clean the joint face, ensure it's clean and tidy. Assemble
the back end plate.
5. Apply sealant on the back end plate, it's continuous and stability.
6. Assemble the camshaft thrust plate and camshaft bolt.
4.2.5 Inspection and repair of camshaft and camshaft timing gear
Key point 1:
Inspection
1) Check if there is wearing on the camshaft surface in touch with tappet, and check if there is
scuffing or wearing on main journal;
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2) Check whether the bolt is bent and deformed. Check the timing gear for teeth collision or
serious wear on teeth surface.
Key point 2:
Assembly
1) If any impact damage is found on the camshaft hole, it is not allowed to repair it for reuse.
2) Be careful not to scratch the camshaft bush when inserting the camshaft.
3) Apply sealant to the thread of the bolt thread.
4.3 Disassembly and assembly of rocker arm and rocker shaft
4.3.1 Exploded view of rocker arm and rocker shaft
Fig. 4- 3 Exploded view of rocker arm and rocker shaft
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No. name No. name No. name
1 Cylinder head 4 Rocker arm set 7 Rocker arm bracket
2 Valve bridge 5 Rocker arm shaft
3 Cylinder pin 6 Hexagon bolt
4.3.2 Pre-assembly Preparation
1. Equipment condition: torque wrench, oil can, oil, small wrench
2. Preparation: remove the cylinder head cover.
4.3.3 Disassembly steps of rocker arm and rocker shaft
1. Turn the crankshaft and check if rocker arm rotates flexibly.
2. Measure the valve clearance and check the change of valve clearance.
3. If the rocker arm cannot rotate flexibly or the valve clearance changes greatly, loosen the
hexagon head bolt, remove the support frame, rocker shaft and intake/exhaust rocker arm
assembly, and mark them to avoid confusion of rocker arms of cylinders.
4.3.4 Assembly steps of rocker arm and rocker shaft
1. Install the cylinder pin into the hole below rocker arm shaft, the pin should be fully in without
crack.
2. Assemble the bracket and rocker arm set, apply little oil on the rocker arm shaft, , make sure it
rotate flexibly.
3. Assemble the push rod and put the valve bridge.
4. Assemble the rocker arm assembly.
Check and adjust intake/exhaust valve clearance:
1. Carry out engine barring, and make 1# cylinder piston at TDC, i.e. the mark line on the
flywheel is aligned with that on the flywheel housing, and determine the 1# cylinder is at
compression TDC;
2. Adjust the intake valve clearance of 1#, 2# and 4# cylinders and the exhaust valve clearance of
1#, 3# and 5# cylinders until the following requirements are met: Intake valve clearance: (0.38
± 0.03) mm; exhaust valve clearance: (0.58 ± 0.03)mm; The tightening torque of
intake/exhaust valve adjusting nut is (45±5)Nm.
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3. Turn the flywheel for 360° to make the 6# cylinder at the compression TDC;
4. Adjust the intake valve clearance of 6#, 5# and 3# cylinders and exhaust valve clearance of 6#,
4# and 2# cylinders clearance. valve clearance: (0.38±0.03) mm; exhaust valve clearance:
(0.58±0.03)mm;
5. Check the valve timing of 1# cylinder in cold state; it is required that the intake valve is open
at （21±5）°before TDC and closed at （34±5）°after BDC; Exhaust valve is open at
（49±5）°before BDC and closed（34±5）°after TDC.
4.3.5 Inspection and repair of rocker arm and rocker shaft
Key point 1:
Inspection
1) Clean the rocker arm and observe its surface for cracks or other defects.
2) Check the rocker arm inner bore for wear and scratches, and measure its diameter.
3) Check the ball pin and the arc surface at the other side of the rocker arm for wear.
4) Check if all oil passages are smooth.
5) Measure the diameter of rocker arm bore and rocker shaft, and calculate the fitting clearance.
6) Check the rocker arm shaft assembly for wear, check the bracket for crack and wear.
Key point 2:
Apply little oil on the rocker arm shaft, , make sure it rotate flexibly.
4.4 Disassembly and assembly of tappet and push rod
4.4.1 Exploded view of tappet and push rod assembly
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Fig. 4-4 Exploded view of tappet and push rod
No. name No. name
1 Engine block 4 Cylinder head
2 Tappet 5 Push rod
4.4.2 Pre-assembly Preparation
1. Equipment condition: oil can, oil
2. Preparation: remove the rocker arm assembly before remove the push rod; remove the cylinder
head before remove the tappet.
4.4.3 Disassembly steps of tappet and push rod
1. Upon removal of rocker arm and rockshaft, take out push rods and place them in order;
2. After the cylinder heads are removed (see disassembly steps of cylinder head), take out tappets
and place them in order.
4.4.4 Assembly steps of valve tappet and push rod
1. Check if any defect occurs in the valve tappet and push rod; if any, renew them. Before
installing the valve tappet, blow it clean with compressed air, and then check if the oil hole is
smooth.
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2. Apply clean lubricating oil to the valve tappet;
3. Place the valve tappet into the tappet hole;
4. After the cylinder head is assembled (see assembly steps of cylinder head), blow the push rod
clean with compressed air, and then check if the oil hole is smooth;
5. Apply clean lubricating oil to the push rod, and ensure that the ball head and socket of push
rod are sufficiently lubricated;
6. Install the push rod into position.
4.4.5 Inspection and repair of tappet and push rod
Key point 1:
Inspection
1) Clean the valve tappet and push rod;
2) Check if the oil passage of valve tappet and push rod is smooth;
3) Check the push rod for bending and the external surface for wear;
4) Check the ball head and socket of push rod for wear;
5) Check the surface and bottom of tappet for wear;
6) Check the internal socket of the valve tappet for wear.
Key point 2:
Assembly
1) Apply clean lubricating oil to the valve tappet;
2) Apply clean lubricating oil to the push rod, and ensure that the ball head and socket of push
rod are sufficiently lubricated;
4.5 Disassembly and assembly of valve
4.5.1 Exploded view of valve
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Fig. 4-5 Exploded view of valve
No. name No. name No. name
1 Intake valve 3
Valve spring top
seat
5 Valve spring
2 Cylinder head 4 Valve collet 6 Exhaust valve
4.5.2 Pre-assembly Preparation
1. Equipment condition: valve spring compressor, valve overhead clamp or other equivalent
tools.
2. Preparation: remove the rocker arm and disassemble the cylinder head from engine block.
4.5.3 Disassembly steps of valve
1. Use a valve spring compressor, valve overhead clamp or other equivalent tools to press the
valve spring and remove the valve collet, valve spring upper seat and inner/outer valve spring;
2. Remove the valve from the valve seat.
4.5.4 Assembly steps of valve
If the valve occurs wear, serious sintering, soot deposition and other defects, replace the valve.
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1. Apply molybdenum disulfide grease on the intake/exhaust valve stem uniformly, and then
install the intake/exhaust valve to the cylinder head, and make sure that the intake/exhaust
valve can slide in the guide pipe without being blocked;
2. Apply thread locking adhesive to the exhaust valve spring lower seat uniformly, and install the
lower seat onto the cylinder head in place, and check if the lower seat is properly seated; when
necessary, remove it for repair or replace with new one, and forced knocking is prohibited;
3. Install the intake valve spring lower seat, place the valve stem protective sleeve onto the
intake/exhaust valve guide, and then install the valve stem seal sleeve;
Note: check if the spring inside the valve stem seal sleeve is intact before installation.
4. Install the inner valve spring and outer valve spring, ensuring that they are reverse in spiral
direction;
5. Install the valve spring upper seat, press the valve spring and install the valve collet;
6. Use a rubber hammer to tap valve collet into the intake/exhaust valve seat after installation; if
the valve collet or valve spring upper seat is not properly seated, find out the causes for
troubleshooting.
4.5.5 Inspection and repair of valve
Key point 1:
Inspection
1) Check the valve stem and valve stem end surface for wear;
2) Check the valve cone for wear or damage;
3) Check the valve cone for soot deposition.
Key point 2:
Assembly
1) The intake/exhaust valve can slide in the guide pipe without being blocked;
2) Check if the spring inside the valve stem seal sleeve is intact before installation.
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4.6 Disassembly and assembly of intermediate gear
4.6.1 Exploded view of intermediate gear
Fig. 4-6 Exploded view of intermediate gear
No. name No. name No. name
1
Intermediate gear
shaft
3 Intermediate gear
5 Intermediate gear
bolt
2 Shaft 4
Intermediate gear
cover
4.6.2 Pre-assembly Preparation
1. Equipment condition: valve spring compressor, valve overhead clamp or other equivalent
tools.
2. Preparation: remove the compressor.
4.6.3 Disassembly steps of intermediate gear
1. Remove the air compressor; see disassembly of complete vehicle accessories for details;
2. Remove the camshaft timing gear; see disassembly of valve train for details;
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3. Check the mark for mounting bolts of intermediate gear, and make sure the bolts have not
rotated. Remove four M10 hexagon head bolts of the intermediate gear bolts and remove the
flange spacer. Screw a M8 bolt into the intermediate gear shaft and pull the shaft out,
preventing the intermediate gear falling off in this process;
4. Demount the intermediate gear assembly and intermediate gear shaft along with the gear
chamber, and remove them out from the opening on the gear chamber.
4.6.4 Assembly steps of intermediate gear
1. Install the oil pump, crankshaft and oil pump intermediate gear assemblies in sequence;
2. Install the gear chamber. Before installing the gear chamber, place the intermediate gear shaft
into the intermediate gear assembly (intermediate gear & bush), keeping the face with "V" on
the intermediate gear outward (i.e. "V" is not to be overlapped by the intermediate gear shaft),
locate the intermediate gear assembly and intermediate gear shaft in the gear chamber into
position. During this installation, keep the diesel engine upside down to prevent the
intermediate gear assembly and intermediate gear shaft from falling off.
4.6.5 Inspection and repair of intermediate gear
1. Check if the mounting bolt thread is in good condition;
2. Check all gears for tooth metal spalling or breakage, the bolt bearing surface for crushing and
the thread hole or through hole in the gear for deformation;
3. Check if any abnormal wear occurs between the intermediate gear shaft and the intermediate
gear bush. Check if the oil hole is blocked by dirt.
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5 Intake/exhaust system
5.1 Disassembly and assembly of intermediate gear
5.1.1 Exploded view of air filter group
Fig 5-1 Exploded view of air filter group
No. name No. name No. name
1 Hexagon bolt 5 Air filter bracket 9 Joint
2 Spring washer 6 Clamp
10 Differential
pressure
transducer
3 Flat washer 7 Intake joint pipe 11 Air filter
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4 Hexagon bolt 8 Plug
5.1.2 Pre-assembly Preparation
1. Equipment condition: air wrench, sleeve
2. Preparation: remove the peripheral parts on the air filter.
5.1.3 Disassembly steps of air filter group
Disassemble the air filter group with the reverse order of assembly.
5.1.4 Assembly steps of air filter group
1. Assemble the air filter bracket onto the air filter, tighten the hexagon bolt with wrench.
2. Assemble the air filter and air filter bracket onto the flywheel housing with the spring washer
and flat washer.
3. Connect the air filter and the intake joint pipe of the mix air with clamp.
5.2 Disassembly and Assembly of Turbocharger System
5.2.1 Explosive View of Turbocharger System
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Figure 5-2 Explosive View of Turbocharger system
No. name No. name No. name
1 Stud 10 Rubber clamp 19 Gasket
2
Turbocharger
gasket
11 Clamp
20 Turbocharger oil
return pipe bolt
3 Hexagon nut 12 Clamp 21 Clamp
4 Block 13 Hexagon bolt
22 Turbocharger oil
pipe
5 Seal washer 14 Turbocharger 23 Pipe joint nut
6
Turbocharger
water pipe
15
Turbocharger
water pipe
24 Clamp
7 Pipe joint 16
Inner hexagon
screw
25 Turbocharger oil
pipe
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8 Seal ring 17 Retaining washer
9 Hollow bolt 18 Washer
5.2.2 Pre-assembly Preparation
Equipment condition: wrench, sleeve
5.2.3 Disassembling Steps of Turbocharger System
1. Loosen the hexagon bolt of the pipe clamp, take away hexagon bolt.
2. Remove the Inner hexagon screw, retaining washer, turbocharger oil inlet pipe gasket and
turbocharger oil inlet pipe.
3. Loosen the oil return pipe bolt of turbocharger, remove oil return pipe, seal washer, retaining
washer and turbocharger oil return pipe.
4. Loosen the hollow bolt of the turbocharger, exhaust gas pipe and oil cooler in turn, remove the
seal washer and water pipe of the turbocharger.
5. Loosen the hexagon bolt of the turbocharger, remove turbocharger, stud and turbocharger
gasket.
6. Loosen the hexagon bolt of block, remove the block, turbocharger gasket and stud.
5.2.4 Assembly steps of turbocharger system
Assemble the turbocharger system with the reverse order of disassembly.
5.3 Disassembly and assembly of exhaust manifold
5.3.1 Exploded view of exhaust manifold
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Figure 5-3 Explosive View of Air Exhaust Manifold
No. name No. name No. name
1 Exhaust manifold 3 Stud 5 Pipe joint
2 Hexagon bolt 4
Exhaust manifold
gasket
6 Seal ring
5.3.2 Pre-assembly Preparation
1. Equipment condition: air wrench, sleeve
2. Preparation: remove the peripheral parts of the exhaust manifold.
5.3.3 Disassembly steps of exhaust manifold
1. Loosen the hexagon bolt of the exhaust manifold;
2. Remove the exhaust manifold, stud and exhaust manifold gasket.
5.3.4 Assembly steps of exhaust manifold
Assemble the exhaust manifold with the reverse order of disassembly.
5.3.5 Overhaul of Exhaust Manifold
1. Check if there is crack or any other damage on the exhaust pipe body, and if there is
deformation of flange, if there is, replace it with new exhaust pipe.
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2. Check if there is indication of air leakage at the position of exhaust pipe flange. If there is, it is
necessary to replace it with a new exhaust pipe gasket.
3. Check if there is deformation, tear, deficiency or any other failure on exhaust pipe gasket. If
there is, it is necessary to replace it.
4. Check if there is sintering, rust, carbon deposit or any other failure on exhaust pipe seal ring. If
there is, it is necessary to replace it.
5. All the bolts and nuts of the gas exhaust system are made of heat-resistant steel, they are can’t
changed to ordinary ones.
5.4 Disassembly and Assembly of Mix Air Intake Pipe
5.4.1 Explosive View of Air Intake Pipe
Figure 5-4 Explosive View of Air Intake Pipe
No. name No. name No. name
1 Hexagon bolt 9 Mixer gasket 17 Air path joint pipe
2 Bracket 10
Mix air intake joint
pipe
18 Pipe clamp
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3 Hexagon bolt 11
Pressure and
temperature
sensor
19 Inner hexagon
screw
4 O-ring 12 Washer 20 Hexagon bolt
5 Washer 13 Pipe 21 Hexagon bolt
6 Wave spiral washer 14 Pipe joint 22 Hexagon bolt
7
Inner hexagon
screw
15
Decompression
valve
23 Hexagon bolt
8 Throttle 16 Clamp 24 Gasket
5.4.2 Pre-assembly Preparation
1. Equipment condition: air wrench, sleeve
2. Preparation: remove the peripheral parts of the exhaust manifold.
5.4.3 Disassembly steps of exhaust manifold
1. Loosen the hexagon bolt of the pipe clamp, remove the bolt.
2. Loosen the hexagon nut of the pipe joint, remove the pipe.
3. Loosen the clamp of the connect hose of the air path.
4. Loosen the hexagon bolt of the decompression valve, remove the decompression valve, gasket
and hexagon bolt.
5. Loosen the inner hexagon screw of the throttle, remove the mix air gasket, throttle.
6. Loosen the hexagon bolt and hexagon nut of the bracket, remove the bracket and mix air joint
pipe.
5.4.4 Assembly steps of exhaust manifold
Assemble the exhaust manifold with the reverse order of disassembly.
5.4.5 Inspection and repair of intermediate gear
1. Check if there is crack, deformation or other damage on the mix air intake pipe, pipe joint and
joint hose of air path , if there is, it is necessary to replace it.
2. Check is there is deformation, tear, deficiency or any other failure on the washer, if there is, it
is necessary to replace it.
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3. Check is there burn out, short circuit or any other damage on the pressure temperature sensor,
if there is, it is necessary to replace it.
4. Check if there is indication of air leakage at the position of exhaust pipe flange, if there is, it is
necessary to replace it.
5.5 Disassembly and assembly of intake manifold
5.5.1 Exploded view of intake manifold
Fig. 5-5 Exploded view of intake manifold
No. name No. name No. name
1 Hexagon bolt 6 Plate washer 11 Joint
2 Hexagon bolt 7 Spring washer 12 Intake manifold
3 Washer 8
Inner hexagon
screw
13 Intake manifold
gasket
4 Clamping clamp 9
Pressure
temperature
sensor
14 Hexagon bolt
5 Hexagon bolt 10
Mix air intake joint
pipe
15 Gasket
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5.5.2 Pre-assembly Preparation
1. Equipment condition: air wrench, sleeve
2. Preparation: remove the peripheral parts of the exhaust manifold.
5.5.3 Disassembly steps of intake manifold
Disassemble the intake manifold with the reverse order of assembly.
5.5.4 Assembly steps of intake manifold
1. Assemble the intake manifold gasket and intake manifold onto the cylinder head with hexagon
bolt.
2. Assemble the pressure temperature sensor into the mix air intake pipe with hexagon.
3. Assemble the gasket and mix air joint pipe onto the intake manifold.
5.5.5 Inspection and repair of intake manifold
1. Check the intake manifold body for cracks and deformation; if any, replace with a new one.
2. Check the intake manifold gasket for deformation, tear, absence or other defects; if any,
replace it.
3. Check the intake heater for burnout or short circuit; if any, replace it.
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6 Ignition System
6.1 Ignition System Assembly and Disassembly
6.1.1 Ignition System Exploded View
Fig. 6-1 Exploded view of ignition system
No. name No. name
1 Inner hexagon bolt 3 Ignition coil
2 Washer 4 Ignition plug
6.1.2 Ignition System Disassembly Steps
1. Remove the install bolt of the ignition coil.
2. Remove the ignition coil.
3. Dismount the sparking plug with the wrench for the sparking plug.
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Fig. 6-2 Exploded view of ignition plug wrench
6.1.3 Ignition System Assembly Steps
1. Tighten the ignition plug with the ignition plug wrench, tighten torque (25-28) nm
2. Assemble the Ignition coil,
3. Fix the ignition coil with M5 bolt.
6.1.4 Ignition System Inspection and Maintenance
1. The normal spark plug head is grey or gray, if the electrode of the spark plug is damage or
melted, change a new spark plug.
2. Check the clearance of the sparking plug with a feeler, the clearance is 0.35mm. The clearance
of each cylinder is same, if it is necessary change it.
Note : Adjust the clearance of the sparking plug if it is not right. If the clearance of the
sparking plug is large, place the feeler in the gap first, then tap the electrode with a small
wrench; If the clearance is small, raise the gap with a small vise, then place the feeler in the
gap, then tap the electrode with a small wrench. When adjusting the clearance, ensure that the
side electrode is parallel to the center electrode.
3. Check the thread of the sparking plug , if it is necessary change it.
4. Check whether the rubber sleeve of ignition coil old or damaged, if there is, it is necessary to
replace it.
Note: remove the rubber sleeve from the axial, don't bend it.
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6.2 Engine Control Unit (ECU) Assembly and Disassembly
6.2.1 Engine Control Unit Exploded View
Fig. 6-3 Exploded view of Engine Control Unit
No. name No. name No. name
1 Hexagon bolt 3 Hexagon bolt 5 Support screw
2 ECU 4 ECU bracket
6.2.2 ECU Disassembly Procedure
1. Remove the fuse box bolts. Remove the fuse box from the bracket.
2. Remove the Harness ECU Connection from the ECU.
3. Remove the ECU bolts. Remove the ECU from the bracket.
6.2.3 ECU Assembly Procedure
Reverse the disassembly procedure to assemble the ECU
6.2.4 Inspection and Maintenance of ECU
1. Check to see if any ECU connection pins are corroded, bent, broken, missing, or damaged.
Replace the pins if necessary.
2. Check the plastic portion of the ECU connection for damage. Replace the ECU if there is any
damage.
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6.3 Signal Generator Assembly and Disassembly
6.3.1 Signal Generator Exploded View
Fig. 6-4 Exploded view of signal generator
No. name No. name No. name
1 Hexagon bolt 5 Hexagon bolt 9 Timing gear
2 Cover 6 Speed sensor 10 Gasket
3 Nut 7
Inner hexagon
screw
11 Bolt
4 Stud 8 Signal generator
6.3.2 Signal Generator Disassembly Procedure
1. Cylinder piston should be in its compression stroke, check the mark of the signal generator
gear and the mark of the signal generator housing are right or not.
2. Remove the fastening bolt of the signal generator, separate Signal generator from timing gear
housing.
3. Remove the fastening bolt of the timing gear, separate the timing gear and signal generator.
4. Remove the hexagon bolt of the speed sensor, separate the speed sensor from signal generator.
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Fig. 6-5 Exploded view of signal generator mark
6.3.3 Signal Generator Assembly Procedure
1. Assemble the timing gear onto the signal generator, fasten with M22 hexagon bolts, the fasten
torque is (290-310) Nm.
2. Assemble the O-ring into the signal generator.
3. Assemble the speed sensor into the signal generator, fasten with M6 hexagon bolts, the fasten
torque is (8-10) Nm.
4. Screw the double-headed stud into the timing gear housing, assemble the signal generator onto
the timing gear housing, fasten with M10 bolt, the fasten torque is (39-46) Nm.
5. Adjust the crankshaft to TDC: the first cylinder piston should be in its compression stroke.
Tighten the connecting bolts between the pump gear and signal generator.
6. Assemble the cover, fasten with M6 hexagon bolt, the fasten torque is (8-10) Nm.
6.3.4 Inspection and Maintenance of Signal Generator
1. Check for damage to the signal generator shaft threads.
2. Check that the locknuts of the signal generator fluted disc are tightened and that the ignition
angle of the signal generator is correct.
3. Change the O-ring and the washer after dismounting.
4. Check for damage to the speed sensor, tooth disc, or housing
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5. Check the clearance between the speed sensor and the fluted disc of the signal generator, it’s
(0.5-0.15) mm.
7 Fuel System
7.1 LPG Intake System Assembly and Disassembly
7.1.1 LPG Intake System Exploded View
Fig. 7-1 Exploded view of LPG supply system
No. name No. name No. name
1 Inner hexagon bolt 12 LPG EPR bracket 23 Plate washer
2 Spring washer 13 Bolt 24 Cover
3 Plate washer 14 Cushion 25 Clamp
4 nut 15 Support block 26 Pipe joint
5 Gas pipe 16 Cushion 27 Cushion
6 Hose 17 solenoid valve 28 Spring washer
7 Clamp 18 Water pipe joint 29 bolt
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8
Outlet water pipe
joint
19 Water pipe joint
30 Plate washer
9 Clamp 20 Three-way joint 31 Cushion
10 Bolt 21 Inner hexagon bolt 32 Gas joint
11 Spring washer 22 Spring washer
7.1.2 Signal Generator Disassembly Procedure
1. Disassemble the joint hose and clamp of the gas pipe, separate the LPG system with NG
system.
2. Remove the water inlet and outlet fitting clamps. Disconnect the LPG evaporator from the
water inlet and outlet hoses.
3. Remove the connecting bolts and isolator cushions between the LPG evaporator and the LPG
bracket. Fully remove the LPG evaporator assembly from the LPG bracket.
4. According to the chart, replace the parts which is needed repaired.
5. Remove the hex nipple fitting between the LPG evaporator and LPG lock-off valve. Separate
LPG evaporator and LPG lock-off valve.
6. Remove the LPG evaporator plug and adapter from the LPG evaporator.
7.1.3 Signal Generator Assembly Procedure
Reverse the Disassembly Procedure to assemble the signal generator.
7.2 Mix air Intake System Assembly and Disassembly
7.2.1 Mix air Intake System Exploded View
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Fig. 7-2 Mix Intake System Exploded View
No. name No. name No. name
1 clamp 6 Hexagon bolt 11 Hexagon bolt
2 hose 7 mixer 12 Intake elbow
3 hose 8 bracket 13 hose
4 Clamp 9 washer 14 clamp
5
mix intake joint
pipe
10 Hexagon bolt
15 Mix intake joint
pipe
7.2.2 Mix Air Intake System Disassembly Procedure
1. Disassemble the clamp between the mix air intake joint pipe and turbocharger, remove the
hose.
2. Disassemble the clamp between the mix air intake joint pipe and intake elbow, remove the mix
air intake joint pipe of the mixer.
3. Disassemble the bolt of the intake elbow, remove the intake elbow.
4. Disassemble the air return pipe of the oil-gas separator, remove the air intake joint pipe.
5. Remove the mixer.
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6. Disassemble the fasten bolt of the mixer bracket, remove the mixer bracket.
7.2.3 Mix Air Intake System Assembly Procedure
Reverse the disassembly procedure to assemble the mix air intake system.
7.3 NG Gas Supply And Gas Flow Control Valve (EPR Valve) Assembly And Disassembly
7.3.1 NG Gas Supply And Gas Flow Control Valve (EPR Valve) Exploded View
Fig. 7-3 Exploded view of NG gas supply and gas flow control valve
No. name No. name No. name
1 Hexagon Bolt 5 Hexagon bolt 9 Nut
2 EPR valve 6 Bracket
10 electromagnetic
valve
3 Gas pipe 7 nut
4 Pipe joint 8 Hexagon bolt
7.3.2 NG Gas Supply And Gas Flow Control Valve (EPR Valve) Disassembly Procedure
1. Disassemble the connect bolt between the EPR valve and the gas pipe, remove the EPR valve.
2. Disassemble the bolt of the electromagnetic valve, remove the electromagnetic valve.
3. Disassemble the bolt of the bracket of the electromagnetic valve, remove the racket.
7.3.3 NG Gas Supply And Gas Flow Control Valve (EPR Valve) Assembly Procedure
Reverse the disassembly procedure to assemble the NG gas supply and gas flow control valve
(EPR valve)
7.3.4 Fuel System Inspection and Maintenance
1. Change the gasket and O-ring after disassembling.
2. Check the joint and clamp, make sure that they are tightened well.
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3. Check the balance tube of the LPG evaporator..
4. Inspect the inlet pressure of the NG, the right pressure is 2.5kpa.
5. Inspect the joint of the gas path, make there is no leakage.
6. Inspect the joint of the gas path, make there is no leakage
7. Inspect whether the gas pipes have cracks and the flanges are deformed, if there is any change
the gas pipe.
8 Cooling System
8.1 Cooling System Disassembly and Assembly
8.1.1 Cooling System Exploded View
Fig. 8-1 Exploded view of cooling system
No. name No. name No. name
1 Radiator 4 Alternator 7 thermostat
2 Fan 5 Water inlet pipe 8 Water outlet pipe
3 Belt 6 Water pump
8.1.2 Disassembling Steps of Cooling System
1. Disassemble the fan and hub. For more details, see Disassembling Instructions for Fan.
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2. Disassemble the tensioning pulley.
3. Disassemble the belts.
4. Disassemble the alternator, alternator support, crankshaft pulley and absorber.
5. Disassemble the alternator and alternator support.
6. Disassemble the thermostat. For more details, see Disassembling Instructions for Thermostat.
7. Disassemble the air compressor and hydraulic pump.
8. Disassemble the water pump water pipe connector and water pump. For more details, see
Disassembling Instructions for water pump.
8.1.3 Assembling Steps of Cooling System
The assembly should be conducted in the reverse order of disassembly.
8.2 Radiator Disassembly and Assembly
8.2.1 Radiator Exploded View
Fig. 8-2 Exploded view of the radiator
No. name No. name No. name
1 Radiator 4 Outlet pipe 7 Inlet pipe
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2 Clamp 5 Water inlet pipe 8 Water outlet pipe
3 Hose 6 Water outlet pipe
8.2.2 Pre-assembly Preparation
Equipment condition: air wrench, sleeve wrench, open end wrench
8.2.3 Disassembling Steps of the radiator
1. Remove the clamp 2 and the hose 3 of the inter cooler pipe, remove the inter cooler pipe 4 and
pipe 7.
2. Remove the clamp 2 and the hose 3 of the water pipe, remove the water pipe 5 and water pipe
6.
8.2.4 Assembling Steps of the radiator
The assembly should be conducted in the reverse order of disassembly.
8.2.5 Inspection and Maintenance of Radiator
1. Carry out the suppression test on the radiator, inter cooler pipe and water pipe before
assembling, make sure there is no leakage.
2. Check the hose, make sure there is no damage on the surface.
8.3 Fan and Hub Disassembly and Assembly
8.3.1 Fan and Hub Exploded View
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Fig. 8-3 Exploded view of the fan and hub
No. name No. name No. name
1 Fan 3 Hub 5 Hexagon bolt
2 Hexagon bolt 4
Hexagon self-lock
bolt
6 Hexagon self-lock
bolt
8.3.2 Pre-assembly Preparation
1. Equipment condition: air wrench, sleeve wrench, open end wrench
2. Preparation: remove the radiator and the pipes.
8.3.3 Disassembling Steps of the radiator
1. Remove the bolt 2 and bolt 4 of the fan 1 and the hub 3, remove the fan 1.
2. remove the bolt 5 and bolt 6, remove the hub 3.
8.3.4 Assembling Steps of the radiator
The assembly should be conducted in the reverse order of disassembly.
8.3.5 Inspection and Maintenance of Fan
1. Before assembly, first check the fan, fan clutch, fan connecting disk and hexagon flange face
bolt to make sure there is no defect or damage in manufacturing and usage.
2. Check the fan, clutch, fan connecting disk or pulley for crack or any other damage on them.
8.4 Water Pump and Water Pump Disassembly and Assembly
8.4.1 Water Pump and Water Pump Exploded View
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Fig. 8-4 Exploded view of the water pump and water pipe
No. name No. name No. name
1 Water pump 4 Hexagon bolt 7 Hexagon bolt
2 Washer 5 Hexagon bolt
8 Hexagon head
screw plug
3 Water inlet pipe 6 Pipe joint
8.4.2 Pre-assembly Preparation
1. Equipment condition: air wrench, sleeve wrench, copper hammer
2. Preparation: remove the belts, remove the alternator
8.4.3 Disassembling Steps
1. Remove the two hexagon bolts 7;
2. Remove the hexagon bolt 4 and bolt 5, remove the water inlet pipe 3 and washer 2;
3. Remove the pipe joint 6 and hexagon head screw plug.
8.4.4 Assembling Steps
The assembly should be conducted in the reverse order of disassembly.
8.4.5 Inspection and Maintenance
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1. Check if there is blockage or crack or any other kind of damage of pipe connector and pipe
connector subassembly. Replace if necessary.
2. Check if there is fracture or any other kind of damage of pipe connector gasket and water
pump gasket. Replace if necessary.
3. Check if there is thread scratch or any other kind of damage of any bolt, stud or nut. Replace if
necessary.
4. Check if there is fracture or any other kind of damage of water pump. Replace if necessary.
8.5 Water Pump Disassembly and Assembly
8.5.1 Water Pump Exploded View
Fig. 8-5 Exploded view of the water pump
No. name No. name No. name
1 Water pump pulley 5 Hexagon bolt 9 Seal washer
2 Stud 6 Water pump gasket
10 Hexagon head
screw plug
3 Hexagon bolt 7 Stud
4 Water pump 8 Stud
8.5.2 Pre-assembly Preparation
1. Equipment condition: air wrench, sleeve wrench, copper hammer
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2. Preparation: remove the belts, remove the alternator
8.5.3 Disassembling Steps
1. Remove the hexagon bolt 5, remove water pump 4 and water pump gasket 6;
2. Remove the stud 7 and stud 8.
3. Remove the hexagon bolt 3, remove water pump pulley 1;
4. Remove stud 2.
8.5.4 Assembling Steps
The assembly should be conducted in the reverse order of disassembly.
8.5.5 Inspection and Maintenance
1. Before assembly, first check the hexagon bolts, supporting block, water pump gasket and
water pump. Make sure there is no defect or damage on manufacturing or use.
2. Clean the inner chamber on gear chamber connecting with the water pump.
3. The assembly should be conducted in the reverse order of disassembly.
4. Check if there is blockage or crack or any other kind of damage of pipe connector and pipe
connector subassembly. Replace if necessary.
5. Check if there is thread scratch or any other kind of damage of any bolt, stud or nut. Replace if
necessary.
6. Check if there is fracture or any other kind of damage of water pump. Replace if necessary.
8.6 Disassembly and Assembly of Thermostat
8.6.1 Explosive View of Thermostat
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Fig. 8-6 Exploded view of the thermostat
No. name No. name No. name
1 Water outlet pipe 7 Water pipe washer 13 Thermostat cover
2 Water pipe washer 8 Blocking cover 14 Hexagon bolt
3 Hexagon bolt 9 Pipe joint 15 Clamp
4 Water pipe 10 Thermostat body 16 Coolant joint pipe
5 Hexagon bolt 11 Inner thermostat
6
Temperature
sensor
12 Blocking cover
8.6.2 Pre-assembly Preparation
1. Equipment condition: air wrench, sleeve wrench, open end wrench, rubber hammer
2. Preparation: remove the belts, remove all the water joint hose of the thermostat
8.6.3 Disassembling Steps of Thermostat
1. Remove the clamp 15 and hose 16.
2. Remove the hexagon bolt 3 and 5, remove the thermostat and washer 2.
3. Remove the hexagon bolt 14, remove the thermostat cover 13.
4. Remove the thermostat 11.
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5. Remove the hexagon bolt 3, separate the thermostat 10 and water pipe 4.
8.6.4 Assembling Steps of the thermostat
1. Before assembly, first, check the clamp, rubber tube clamp, rubber tube, thermostat,
thermostat head, and make sure there is no defect or damage on manufacturing or use.
2. Clean up the water outlet pipe and water pump water outlet pipe, and make sure no foreign
matter comes into them.
3. The assembly should be conducted in the reverse order of disassembly. Parameter table of
thermostat opening temperature
8.6.5 Inspection and Maintenance
1. Check if there is failure or any other damage of the four clamps. If there is, it is necessary to
replace with intact clamps.
2. Check if there is crack or any other damage of coolant-connecting rubber tubes. If there is, it is
necessary to replace with intact coolant-connecting rubber tubes.
3. Check if there is crack or any other damage of thermostat. If there is, it is necessary to replace
with intact thermostat.
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9 Lubrication System
9.1 Disassembly and Assembly of Lubrication system
Fig. 9-1 Schematic Diagram of Lubrication System
9.1.1 Explosive View of Lubrication System
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Fig. 9-2 Exploded view of lubrication system
No. name No. name No. name
1 Oil pump 5 Dipstick 9 Bypass valve
2 Oil pan 6 Oil filter 10 Oil filling pipe
3 Oil strainer 7 Oil cooler cover
4
Main oil passage
limiting valve
8 Oil cooler
9.1.2 Disassembling Steps of Thermostat
1. Disassemble the oil sump. For more details, see Disassembling Instructions for Engine Block
Combination.
2. Disassemble the strainer.
3. Disassemble the crankshaft pulley, absorber and hexagon plug screws on gear chamber. For
more details, see Disassembling Instructions for Crank-Connecting Rod Mechanism.
4. Disassemble the oil pump intermediate gear subassembly.
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