WEICHAI WP6GTA User manual

Assembly & Disassembly Manual
Gas Engine
Model: WP6GTA
WEICHAI AMERICA CORP.

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Purpose
This manual is intended to inform customers on how to assemble and disassemble theWeichai America
6 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 be sure to follow proper warranty procedures.(see Weichai America CorpWarranty Procedure
Manual)

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Table of Contents
1Disassembly & 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
2Engine block assembly........................................................................................................6
2.1 Disassembly and assembly of engine block assembly......................................................6
2.2 Steps to Assemble and disassemble Engine Block Module..............................................8
2.3 Gear Housing Assembly and Disassembly .....................................................................10
2.4 Assembly and disassembly of piston nozzle...................................................................13
2.5 Assembly and disassembly of thrust plates.....................................................................15
2.6 Assembly and disassembly of front oil seal and rear oil seal...........................................15
2.7 Assembly and disassembly of flywheel housing..............................................................17
2.8 Assembly and disassembly of oil sump...........................................................................20
2.9 Cylinder Heads Assembly and Disassembly...................................................................21
2.10 Cylinder Head Cover Assembly and Disassembly................................................25
2.11 Lifting Lugs Assembly and Disassembly...............................................................26
2.12 CCV Breather System Assembly and Disassembly ..............................................27
2.13 CCV Breather Assembly and Disassembly...........................................................29
3Crank-rod mechanism........................................................................................................30
3.1 Assembly and disassembly of crank-rod mechanism......................................................30
3.2 Assembly and disassembly of crankshaft system ...........................................................30
3.3 Assembly and disassembly of crankshaft bearing shell...................................................33
3.4 Assembly and disassembly of flywheel and ring gear .....................................................34
3.5 Assembly and disassembly of piston-rod assembly........................................................35
3.6 Assembly and disassembly of torsional vibration damper Crankshaft belt pulley and Hub38
4Valve train..........................................................................................................................40
4.1 Disassembly and assembly of valve train .......................................................................40
4.2 Assembly and disassembly of camshaft .........................................................................40

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4.3 Intermediate Gear Assembly and Disassembly...............................................................43
4.4 Tappet and Pushrod Assembly and Disassembly...........................................................44
4.5 Assembly and disassembly of valve................................................................................46
4.6 Rocker and Rocker Shaft Assembly and Disassembly....................................................47
5Intake and Exhaust System ...............................................................................................50
5.1 Intake and Exhaust System Assembly and Disassembly................................................50
5.2 Intake Manifold Assembly and Disassembly...................................................................51
5.3 Exhaust Manifold Assembly and Disassembly................................................................52
5.4 Disassembly and assembly of turbocharger system .......................................................54
6Ignition System..................................................................................................................58
6.1 Ignition System Assembly and Disassembly...................................................................58
6.2 Signal Generator Assembly and Disassembly ................................................................59
6.3 Engine Control Unit (ECU) Assembly and Disassembly..................................................62
7Fuel System.......................................................................................................................64
7.1 Fuel System Assembly and Disassembly .......................................................................64
7.2 Mix air Intake System Assembly and Disassembly .........................................................66
7.3 NG Gas Supply And Gas Flow Control Valve (EPR Valve) Assembly And Disassembly.68
8Cooling System..................................................................................................................70
8.1 Cooling System Disassembly and Assembly ..................................................................70
8.2 Water Pump Assembly and Disassembly .......................................................................71
8.3 Thermostat Disassembly and Assembly.........................................................................72
9Lubrication System............................................................................................................74
9.1 Disassembly and Assembly of Lubricating System.........................................................74
9.2 Disassembly and Assembly of Engine Oil Pump.............................................................75
9.3 Disassembly and Assembly of Engine Oil Filter..............................................................76
9.4 Disassembly and Assembly of Engine Oil Cooler............................................................76
9.5 Disassembly and Assembly of Main Oil Gallery Pressure Limiting Valve........................77
9.6 Disassembly and Assembly of Deputy Oil Pressure Limiting Valve.................................78
9.7 Disassembly and Assembly of Engine Oil Strainer..........................................................79

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10 Starting System....................................................................................................80
10.1 Starting System Assembly and Disassembly........................................................80
11 Engine Accessory System....................................................................................81
11.1 Engine Accessory System Assembly and Disassembly........................................81
11.2 Alternator Assembly and Disassembly..................................................................82

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1Disassembly & 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 are 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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2Engine block assembly
2.1 Disassembly and assembly of engine block assembly
2.1.1 Exploded view of engine block assembly
Fig. 2- 1 Exploded view of engine block assembly
No.
name
No.
name
No.
name
1
Engine block
11
Rivet
21
Plug
2
Pin
12
shaft
22
Rivet
3
Cup plug
13
Camshaft bushing
23
Stud
4
Camshaft bushing
14
Camshaft bushing
24
Cup plug
5
Cylinder liner
15
Pin
25
Dipstick
6
O seal ring
16
Plug

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7
O seal ring
17
Stud
8
Seal plug
18
Pin
9
Cup plug
19
Stud
10
Rivet
20
washer
2.1.2 Steps to disassemble engine block
1. Remove cylinder head bolt (key point 1)
2. Remove oil dipstick assembly.
3. Remove oil pipe plus screw and swivel nut
4. Remove cylinder liner (key point 2)
5. Remove camshaft bushing
2.1.3 Steps to assemble engine block assembly
Assembling steps are contrary to disassembling ones.
2.1.4 Inspection and maintenance of engine block assembly
Key point 1:
Inspection：
(1) Measure the protrusion of cylinder sleeve (0.05mm~0.10mm is qualified).
Note that protrusion of cylinder sleeve is average value of X direction and Y direction; and the
measurement should be done without seal rings. Cylinder sleeve for the same engine should be
uniform.
(2) No corrosion, scratch and crash damage is allowed for fitting surface and friction surface,
wipe them out and apply clean lubricating oil or grease before assembling.
Assembling:
Place cylinder sleeve vertically on engine block, install seal rings on the sleeve and engine block
and then assemble the sleeve, knock it to the right place evenly with nylon rod.
Key point 2:

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Disassembling:
Use dedicated tool to disassemble the camshaft sleeve, and try to protect other sleeves during
disassembling.
Inspection:
Before assembling, grease on sleeve back, bush surface and fitting hole inner surface must be
wiped out, and make sure there is no burr, overlap and scrap iron.
Assembling:
Apply oil on engine block hole, put camshaft sleeve into the dedicated tool and guide it into
engine block, in the meantime align oil gallery holes on the sleeve and engine block.
Key point 3:
Assembly: Install the greased seal ring to the welded elbow, insert the elbow into the
corresponding hole, and fix it on the engine block by using a fixing plate, hexagon socket bolts
and spring washers.
2.2 Steps to Assemble and disassemble Engine Block Module
2.2.1 Exploded View of Engine Block Module

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Fig. 2-2 Exploded view of engine block
2.2.2 step to disassemble Engine Block Module
1. Remove main bearing bolts (key point 1);
2. Remove main bearing caps (key point 2);
2.2.3 Steps to assemble engine block module.
Assembling steps are contrary to disassembling ones.
2.2.4 Inspect and repair engine block module.
Key point 1:
Inspection:
Check and clean engine block. Including but not limited to: Assembly environment must be
clean; check engine block finished surfaces for crash damage, scratch and rust; do not bump and
scratch the parts during assembling, and besides special requirements, sharp corner and edge on
parts must be smoothed.
Assembling:
For 6-cylinder engine, 14 M14－10.9 main bearing bolts are used to fix the bearings. As shown
in Fig. 2-3, start with middle bearings, do the tightening work from middle to two ends evenly,
follow the procedures below: Firstly pre-tighten each bolt to 70Nm, and tighten the bolts for
further 90°±4°.
Fig.2- 3 Tighten order of main bearing bolt

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Key point 2
Installation: Install the thrust bearing cap on the rear end of cylinder block, and install non-thrust
bearing caps to other positions. Pay attention to distinguishing two ends of the bearing cap for a
proper positioning, and if the bearing cap is reversed, the main bearing bolt cannot be mounted.
2.3 Gear Housing Assembly and Disassembly
2.3.1 Gear Housing Exploded View
Fig. 2-4 Exploded view of Gear Housing
No.
name
No.
name
No.
name
1
Front end cover
4
washer
7
bolt
2
bolt
5
bolt
3
bolt
6
bolt
2.3.2 Gear Housing Disassembly Procedure
1. Remove the intermediate gear.
2. Remove the front cover plate (key point 1).

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3. Remove the front oil seal (key point 2).
2.3.3 Gear Housing Assembly Procedure
Reverse the Disassembly Procedure to assemble the Gear Housing.
2.3.4 Gear Housing Inspection and Maintenance
Key Point 1:
Inspection:
Check the gear housing to ensure that it is clean and without any damage or burrs on the fitting
surface. Check the O-Rings to ensure that they are in good condition. Replace the O-Rings if
necessary.
Assembling:
(1) Knock the locating pins into place, as shown in the figure below;
Fig. 2-5 Locating pin installation for Gear Housing
(2) Apply sealant on the sealing surface of the Gear Housing. Ensure that the sealant is evenly
distributed and continuous.

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Fig. 2-6 Sealing surface of Gear Housing
(3) Place the gear housing with alignment pins in the pin holes. Knock the cover edge gently with
a nylon rod such that the cover and engine block can fit together closely.
Fig. 2-7 Gear Housing installation
(4) Place the bolts with gaskets in their corresponding holes. Tighten them with a pneumatic
impact wrench and an open-end wrench.

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Fig.2- 8 Tighten order of gear housing bolt
Key Point 2:
Assembling:
Oil seals and seal rings should be checked before assembling. Ensure there is no damage or dirt.
For a tight seal, apply some clean engine oil on the shaft first, and then press the seal in slowly
with the dedicated tool, ensuring that the pressing force is evenly distributed on the seal.
Disassembling:
The removed oil seal cannot be reused; replace it with a new one
2.4 Assembly and disassembly of piston nozzle.
2.4.1 Exploded view of piston nozzle

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Fig. 2-9 Exploded view of piston nozzle
2.4.2 Steps to disassemble piston nozzle.
1. Remove the hexagon bolt (key point 1)
2. Remove the piston nozzle (key point 2)
2.4.3 Steps to assemble piston nozzle
Assembling steps are contrary to disassembling ones.
2.4.4 Inspection and maintenance of piston nozzle.
Key point 1:
Assembling:
(1) Compress nozzle module tightly with bolt (with spring washer) and pressing plate;
(2) Place the pressing plate in nozzle end face groove.
(3) Bolts tightening
Key point 2:

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Inspection: Check O-shape seal ring for damage; make sure the nozzle is clean and free of burr.
2.5 Assembly and disassembly of thrust plates.
2.5.1 Exploded view of thrust plates.
Fig. 2-10 Exploded view of thrust plates
2.5.2 Steps to disassemble thrust plates
1. Remove main bearing cap (refer to disassemble engine block module steps)
2. Remove crankshaft (refer to disassemble crankshaft steps)
3. Remove thrust plates (key point 1)
2.5.3 Inspection and maintenance of thrust plates
Key point 1:
Assembling
Thrust plate should be used in pairs and the side with oil groove should be outward during
assembling. Put the anti-miss loading lug in corresponding groove of thrust bearing cap.
2.6 Assembly and disassembly of front oil seal and rear oil seal
2.6.1 Exploded view of front oil seal and rear oil seal.

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Fig. 2-11 exploded view of front oil seal and rear oil seal
2.6.2 Steps to disassemble front and rear oil seal
1. Remove gear housing plate
2. Remove engine front oil seal
3. Remove engine rear oil seal cover (Key point 1)
4. Remove engine rear oil seal (key point 2)
2.6.3 Steps to assemble front and rear oil seal
Assembling steps are contrary to disassembling ones.
2.6.4 Inspection and maintenance of engine front and rear oil seal.
Key point 1:
Inspection
Check whether the junction surface between rear oil seal cover and engine body is cleaning or
knocking wound.
Assembling
(1) Clean the junction surface and install 2 pins into engine body.
(2) Apply sealant on the junction surface of rear oil seal cover.

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(3) Apply oil on surface of crankshaft flange, assemble rear oil seal and tighten bolt. Bolt
tightening sequence is: 1-2-6-7-3-4-5-8-9-10。
Fig. 2-12 tightening sequence of rear oil seal cover bolt
Key point 2:
Inspection:
Oil seals and seal rings should be checked before assembling, make sure there is no damage.
Check whether rear oil seal cover is clean and whether its finished surface is free of obvious
scratch.
Assembling
Apply sealant on the rear oil seal outer ring first, and then press-in the seal slowly with dedicated
tool. NOTICE: Do not damage the seal during assembling, and seal outer ring should be parallel
and level to oil seal cap plane.
2.7 Assembly and disassembly of flywheel housing
2.7.1 Exploded view of flywheel housing

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Fig. 2-13 Exploded view of flywheel housing
No.
name
No.
name
No.
name
1
connector
4
bolt
7
Speed sensor
2
bolt
5
Inspect window
8
bolt
3
Flywheel housing
6
bolt
9
plug
2.7.2 Steps to disassemble flywheel housing
1. Remove fixing bolts of flywheel housing (Key point 1).
2. Remove speed sensor
3. Remove fixing bolts of monitoring window cap on flywheel housing, take down the cap;
4. Remove flywheel housing (key point 2).
2.7.3 Steps to assemble flywheel housing.
Assembling steps are contrary to disassembling ones.

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2.7.4 Inspection and maintenance of flywheel housing.
Key point 1:
Assembling
Check whether flywheel is cleaned up. Debut the corresponding fitting surface on engine block
with 240# fine oil stone and clean the surface with ethyl alcohol. Apply sealant on fitting surfaces
of flywheel housing and engine block. Bolts and tools: M10-10.9 hexagon bolts (×12), M12-10.9
hexagon bolts (×6), 17mm and 19mm socket spanner.
Step 1: Preassemble the bolts
Step 2: Follow the sequence of arrow to tighten the M10 bolts, tighten torque for M10 bolts is
80~85Nm. And then tighten the M12 bolts according to the marked order 1-2-3-4-5-6, tighten
torque for M12 bolts is 140~145Nm.
Fig. 2-14 tightening sequence of flywheel housing
NOTICE: For the strengthening bolts listed above, the thread and bearing surface of each bolt
should be applied with lubricating oil before assembling.