JAC S2. Engine. Service Manual

Engine Mechanical System

Engine Mechanical System 17

type

HFC4GB2
.3D

Max torque(N·m)

1
4
6

Max torque r pm(r/min)

3500~4
500

idle (r/min)

750
±30

full load min fuel consumption (g/kw.h)

2
4
5

engine oil consumption ratio at rated power

≤ 0.15%

crankshaft rotation direction(facing power output ) anticlockwise

Starting method

Electric starting

Lubrication method

Mixed Type of pressure and spatter

Cooling method

Water cooling

New engine oil filling volume (L)

4
.
5

Outside dimension ( length × width× hight )mm

560×543×608

Net weight (kg)

8
8

Fuel type

93# and above

Engine oil type

Environment temperature

Quality degree

SAE 5W/30

-30 ℃~ 30 ℃

SJ and above

SAE 15W/40

-20 ℃~ 40 ℃

SJ and above

Main parts specs

Part name

Technical characteristics

Engine oil filter

full flow type filter thread specs M20×1.5-6H

oil pump

Inner meshing rotors type

cooling water pump

centrifugal

Thermostat

wax type, initial temperature:82 ℃ ; full open temperature:95 ℃

Generator

Built-in regulator alternator specs 14V 90A

starter

Permanent magnet decelerating type starting voltage 12V, power
1.2kW

ignition plug

Iridium platinum alloy type

Oil pressure guide rail

No oil back

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Engine Mechanical System

Engine Mechanical System 19

Items

Standard value

Extreme rate

valve edge thickness (mm)

Intake valve

1.35

0.85

Intake valve

1.85

1.35

valve stem diameter (mm)

φ5.5

clearance between the valve guide and valve
stem (mm)

Intake

0.020

～ 0.036

0.10

Intake

0.030

～ 0.045

0.15

Valve taper angle

45°

～ 45.5°

Valve length (mm)

Intake valve

89.61

89.11

Intake valve

90.94

90.44

Valve spring free height(mm)

43.1

42.7

Valve spring load /installation height (N)/ (mm)

152/33.4

310/25.2

Valve springs verticality

小于 2°

4°

Contact width of the valve seat(mm)

0.9

～ 1.3

valve guide inner diameter(mm)

φ5.5

Valve guide projection amont (mm)

13±0.3

Oil pump gear tip clearance (mm)

0.06

～ 0.18

0.2

Oil pump side clearance (mm)

0.04

～ 0.11

0.15

Oil pump shell clearance (mm)

0.10

～ 0.18

0.2

Piston skirt diameter(mm)

74.968

～ 74.978

Top compression ring side clearance (mm)

0.03

～ 0.07

0.10

Second compression ring side clearance (mm)

0.02

～ 0.06

0.1

Top compression ring opening clearance(mm)

0.15

～ 0.30

0.8

Second compression ring opening clearance (mm)

0.30

～ 0.50

0.8

compound oil ring opening clearance (mm)

0.20

～ 0.50

1.0

piston pin outer diameter(mm)

18.002

～ 18.005

Connecting rod journal clearance (mm)

0.02

～ 0.04

0.1

Connecting rod

big head clearance (mm)

0.10

～ 0.25

0.4

Crankshaft axial clearance(mm)

0.09

～ 0.27

crankshaft main journal diameter (mm)

46.004

～ 46.029

Connecting journal diameter (mm)

39.982

～ 40.0

crankshaft main journal neck clearance (mm)

0.02

～ 0.04

Cylinder pad surface flatness (mm)

0.03

以下

Cylinder total height(mm)

280

Cylinder cylindricity (mm)

0.007

bore inside diameter (mm)

75.000

～ 75.015

Clearance between the piston and cylinder (mm)

0.02

～ 0.04

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Engine Mechanical System

Engine Mechanical System 20

Main inspection and adjustment parameters

Valve clearance (mm)

Intake valve 0.22±0.03

exhaust valve0.30±0.03

emission standard

euro

Oil pressure

Idle oil pressure >100kPa

Oil temperature

≤ 135 ℃

Water temperature

≤ 110 ℃

Spark plug electrode clearance

0.7

～ 0.8mm

Sealant

Seal location

No. Sealant

Crankshaft rear oil seal component - body

1 DowCorning 3-0115 Gasket sealant adhesive

2 Threebond 1217G

3 Ksetra-ksetrajna new 1590

oil sump - engine body - Crankshaft rear oil seal
component

4 DowCorning 3-0115 Gasket sealant adhesive

5 Threebond 1217G

6 Ksetra-ksetrajna new 1590

Sprocket wheel cover –engine body –cylinder
cover

7 DowCorning 3-0115 Gasket sealant adhesive

8 Threebond 1217G

9 Ksetra-ksetrajna new 1590

Bowl type plug - cylinder cover

10 Loctite 12086 bowl type plug sealant

Crankshaft signal wheel bolt

11 Loctite 262 threaded fastening adhesive

water temperature sensor

12 Ksetra-ksetrajna new 1243

thread

sealant

oil pressure switch

13 Ksetra-ksetrajna new 1243

thread

sealant

Lubricant

Engine oil type

Environment Temperature

Quality degree

SAE 5W/30

-30 ℃~ 30 ℃

SJ and abve

SAE 15W/40

-20 ℃~ 40 ℃

SJ and abve

(IV)Torque parameter

Key parts torque table

No.

item

torque (N·m)

remark

Main bearing cap bolt

(35±2)N·

m+60°

～ 64°

M9×1.25×74.5

connecting rod bolt

5N·

m → 10N·

m →

13N·

m+45°+45°

M6×0.75×33

The camshaft bearing cover bolts

11±1

M6×1×35

The camshaft front end bearing cap bolts

20±1

M8×1.25×30

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Engine Mechanical System

Engine Mechanical System 21

No.

item

torque (N·m)

remark

Cylinder cap bolt

(24.5±2)N·

m+180°

～

184°

M9×1.25×143.5

The crankshaft pulley bolt

(50±2)N·

m+(60±2)°

M14×1.5×54

Flywheel bolt

100±5

M11×1.25×25

Exhaust camshaft sprocket bolt

88±10

M12×

Valve timing adjuster bolt

70±5

M10×

Crankshaft rear oil seal bolt

7.6±0.6

M6×10 E8

Rear ear stud

18.4±1.4

M8×20 E10

Intake manifold bolt

18±1.0

M8×40 E10

Oil sump bolts

11±1.0

M6×12 E8

Sprocket cover boltsⅠ

39.5±3.0

M10×90 E14

Sprocket cover boltsⅡ

39.5±3.0

M10×50 E14

Sprocket cover boltsⅢ

8.4±0.6

M6×30 E10

M6×20 E10 type bolt

8.4±0.6

M6×20 E10

M6×12 E10 type bolt

8.4±0.6

M6×12 E10

M6×45 E10 type bolt

8.4±0.6

M6×45 E10

M6×25 E10 type bolt

8.4±0.6

M6×25 E10

M6×12 E8 type bolt

8.4±0.6

M6×12 E8

Cylinder head cover bolt

9±1.0

M6×27 E10

Oil filter Bracket bolt

20±1

M8×30 E12

Warm wind backwater pipe bolt

7.6±0.6

M6×20 E8

Oil pressure guide rail bolt

18.4±1.4

M8×35 E12

Main oil passage cloggingⅠ

60±5

内 VI 角 M20

Main oil passage cloggingⅡ

35±5

内 VI 角 M12

drain screw

25±5

内 VI 角 M12

oil passage clogging

20±2

内 VI 角 M10

VVT oil passage clogging

44±5

M14×1.5×14

Oil drain plug

39±5

M14×1.5×14

Fixed rail bolt components

10±2

M6×1×1

Moving rail bolt components

23.5±4.5

M8×1.25×15

Starter bolt

24±3

M8×

oil pressure switch

10±2

1/8

Spark plug

～ 30

1
4

Exhaust manifold double-headed stud

12±2

M8×1×1

Q1840816(Exhaust manifold bracket bolts )

～ 25

M8×

Catalysts insulation cap nut

10±1

×1

The crankshaft signal wheel bolt

12.5±2.5

M
6

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Engine Mechanical System

Engine Mechanical System 23

No.

Item

Torque (N·m)

remark

Hall sensor bolt

8~10

Inner six flower M6×1×16

knock sensor bolts

20±4

Inner six flower M8×1.25×30

Exhaust manifold nut

35±2

Throttle self-drilling bolt

8~10

Inner six flower M6×1×25

square-head bolt

47±5

M10×1.25×90

idle pulley bolt

49±9

M10×1.25×38

Oil filter

After Installation surface contact,
rotate 3/4 rounds or

(11±1) N·m

idle pulley assembly

50±5

M10×1.5

Standard component torque

No.

item

torque(N·m)

remark

～ 11

～ 25

M10

～ 50

M12

～ 80

(V)Precautions of maintenance

general precautions

1. Precautions of exhausting engine coolant

1). Exhaust engine coolant after engine cools off.

2. Precautions of disconnecting fuel pipe

1). Make sure there is no matters that could trigger spark or fire before working.

2). Release fuel pressure before disconnecting and dissolving.

3). After disconnecting pipe, gag the opening in case fuel will leak.

3. Precautions of removing and disassembly.

1). Please use special maintenance tools when it is required. Be safe, do not disobey the

instructions.

2). Be careful enough not to damage the matching surface and sliding suface.

3). If necessary, gag the opening of engine system with adhesive tape or something similar in case

foreign matters will get inside.

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Engine Mechanical System

Engine Mechanical System 24

4). Label and tidy the dissolved components in order, which is helpful to troubleshoot and

reassembly.

5). The basic principle of loosening nut and screw is: loosen the outer ones first, then those on

the diagonal, and so on. Please follow the appointed order if it is instructed.

4. Precautions of inspection /maintenance and replacement

1). Check the components thoroughly before maintenance or replacement. Please replace if

necessary.

5. Precautions of assembly

1). Use torque wrench to tighten nut and screw.

2). The basic principle of tightening nut and screw is: tighten the center ones first, then those on

the diagonal, with the same force. Please follow the appointed order if it is instructed.

3). Replace new pad, oil seal or “O”type ring.

4). Wash, clear and dry every component thoroughly. Check carefully if engine oil or coolant

pipe is blocked.

5). Try not to damage sliding surface or matching surface, clear foreign matters like kerf or dust

thoroughly. Smear sliding surface with engine oil before assembly.

6). When refill engine coolant after drilling, release air in the pipe.

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Engine Mechanical System

Engine Mechanical System 25

7). Start the engine and increase the rpm to check if there is leakage with engine coolant, fuel

engine oil and intake/exhaust after maintenance.

6. Those parts need to be tightened with certain degree

1). Tighten the following engine parts finally with angle wrench:

·Cylinder cap bolt

· Main bearing cap bolt

· Rod cap nut

2). Please do not tighten finally according to torque value.

3). Torque of these components is applicable for pre –tighten procedures.

4). Make sure the clear thread and base surface and smear engine oil

Precautions of sealant

1. Remove sealant

1). After removing fixing nut and screws, separate matching surface with scraper and remove the

old sealant.

△Caution Be careful not to damage matching surface. Insert scraper, and then knock side

surface to slide as per the drawing. Please use rubber hammer knock component

slightly to remove when it is hard to use scraper. Please be careful not to damage

matching surface if it is unavoidable to use tools like screwdriver.

2. Employing procedures of sealant

1). Clear the old sealant sticked to the application surface and matching surface of gasket with

scraper.

△Caution Clear the old sealant thoroughly off the groove of application surface of sealant, fixed

bolts and bolt hole.

2). Wipe the application surface and matching surface of sealant with unleaded gasoline, clear

attached water, grease and foreign matter.

3). Put the sealant with appointed size at appointed place.

△Caution

。If there is groove to put sealant, please put the sealant in the groove. Generally,

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Engine Mechanical System

Engine Mechanical System 26

put the sealant into the inner side of bolt hole, occasionally, outside, for the bolt hole. Install

and connect components within 5 mins after smear the sealant. Please clear the blot if there is

blot on the sealant. Please do not tighten again bolt and nut after installation.

Refill engine oil and engine coolant 30 mins after installation

△Caution Please operate according to the instruction if there is special instruction.

(VI)Special tool

No.

Tool

Outside figure

Instruction

fork clamp

Fixed camshaft timing gear

use with fork clamp

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Engine Mechanical System

Engine Mechanical System 27

No.

Tool

shape drawing

Description

The flywheel stop

Fixed

flywheel

Valve spring
compressor

Compression valve spring

Oxygen sensor sleeve

Remove and install the oxygen sensor

oil sump disassemble
tool

Disassemble oil sump

Valve oil seal installer

Install valveoil seal

Crankshaft front oil

seal guide

Play the role of guiding when installing
crankshaft front oil seal

Crankshaft front oil

seal installer

Install engine crankshaft front oil seal

Crankshaft rear oil seal

installer

Install crankshaft rear oil seal

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Engine Mechanical System

Engine Mechanical System 29

II failure diagnosis

(I)Diagnosis analysis table

No. Failure

description

Reason analysis

Solution

Starter does not
rotate

The connection of battery electrode becomes
loose or battery is low

tighten or charge

circuit is disconnected

check and repair

Starter has damage

Repair or change

Spark plug does not
ignite

ground connection is poor

repair

Ignition coil damage

change

spark plug clearance is not appropriate or burnt Adjust or change

Electronic ignition system has fault

Repair or change

failure in oil supply
system

gasoline pump is insufficient in oil supply

Repair or change

Petrol hose and fuel filter clogging

Clear

Cylinder
compression
pressure decreases

cylinder pad rupture

replace

Valve clearance adjustment is improper or
damaged

adjust/ repair or change

piston/

piston ring/cylinder wear

Repair or change

valve seal is poor

Repair

underpower during
running

the adjustment between acceleration pedal and
Throttle Valve is not appropriate

Adjust

cylinder compression pressure decreases

1. check if valve/spark plug/cylinder

pad leaks

2. cylinder grind

fuel supply not sufficient

Adjust or repair

air intake not sufficient

check intake system

exhaust clogging

check exhaust system, and clear the
carbon deposition

spark plug clearance inappropriate or damaged adjust or change

There is combustion
knock inside the
engine

bearing bush wear/ crankshaft cam wearing

Replace

Crankshaft/connecting rod axial diameter and
piston pin wear off greatly

Replace or repair

Piston ring damage

change

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Engine Mechanical System

Engine Mechanical System 31

No. Failure description

Reason analysis

soluti

engine overheating

Thermostat failure

Change

generator belt(water pump belt ) tensile
force not enough

Adjust

coolant not enough or water pipe block

Supplement or clear

Water pump clearance inappropriate or
damaged

Repair or replace

Radiator is blocked by incrustation

Repair or replace

Engine oil not enough

supplement

oil circuit blocked or oil pump damaged

clear or replace

spark plug clearance inappropriate or there
is carbon

deposition

clear or adjust

exhaust pipe blocked

tighten or clear

cylinder pad damaged

Replace

clutch slide

repair or replace

Excessive consumption of
engine oil

valve oil seal wear or damaged

Replace

Valve and valve duct wear

Replace

Oil ring wear or damaged

Replace

piston ring is wrongly opened according to
regulation

Replace

cylinder pad damaged

Replace

engine overheating

、inner pressure

increase

、part of the engine oil drained

out through exhaust exit

check related parts and excluded

oil return is not smooth in respiratory
system of cylinder cover shield, leading
engine oil goes into intake system through
respiratory hose

replace or clear cylinder cover
shield

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JAC S2. Engine. Service Manual - part 2