Assembly & Disassembly Manual

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Assembly & Disassembly Manual

Gas Engine

Model: WP10GTA

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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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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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2 Engine Block Group

2.1 Disassembly and Assembly of Engine Block Group

2.1.1 Explosive View of Engine Block Group

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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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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

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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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. 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

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.

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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

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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

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.

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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

1 Seal ring 3 Hexagon bolt 5 Hexagon bolt

2 O-ring 4 O-ring 6 Hexagon plug screw

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;

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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

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1 Piston nozzle

assembly 3 Elastic cylinder pin

5

2 Nozzle 4 Hollow bolt 6

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

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

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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. 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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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. 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.

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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

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Figure 2-11: Explosive View of Flywheel Housing

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

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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

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

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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;

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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;

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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

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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

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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.

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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

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

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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

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Figure 2-21 Explosive View of Oil-air Separator

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;

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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

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connecting rod

5 Main bearing shell 10 Engine block

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

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

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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 2ndring

Piston pin in horizontal direction

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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

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1 Crankshaft 2 Main bearing upper shell

3 Main bearing lower

shell

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

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Fig 3-8 Exploded view of flywheel and ring gear

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)

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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

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2 vibration damper 4 Bolt

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

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Fig. 4-1 Exploded view of valve train

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

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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

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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

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.

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

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1 Cylinder head 4 Rocker arm set 7 Rocker arm bracket

2 Valve bridge 5 Rocker arm shaft

3 Cylinder pin 6 Hexagon bolt

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

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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

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

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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

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

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

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Fig. 4-5 Exploded view of valve

1 Intake valve 3 Valve spring top

seat

5 Valve spring

2 Cylinder head 4 Valve collet 6 Exhaust valve

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

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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

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

1 Intermediate gear

shaft 3 Intermediate gear

5 Intermediate gear

bolt

2 Shaft 4 Intermediate gear

cover

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

1 Hexagon bolt 5 Air filter bracket 9 Joint

2 Spring washer 6 Clamp

10 Differential

pressure transducer

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4 Hexagon bolt 8 Plug

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

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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

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8 Seal ring 17 Retaining washer

9 Hollow bolt 18 Washer

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

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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

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

1 Hexagon bolt 9 Mixer gasket 17 Air path joint pipe

2 Bracket 10 Mix air intake joint

pipe

Assembly & Disassembly Manual