8cab & covering parts system_englisg-g9165

Service Manual of G9165 Grader

8 Cab & Covering Parts System

SERVICE MANUAL

Service Manual for G9165 Grader

I

CONTENTS

8 Cab & Covering Parts System ............................................................................. 8-1

81 Overview of Cab .................................................................................................. 8-1

811 Cab Exterior Description ............................................................................. 8-1

812 Cab Interior Description .............................................................................. 8-3

82 A/C System Description .................................................................................... 8-14

821 Function and Location of Components ..................................................... 8-14

822 System Description .................................................................................... 8-15

83 Disassembly and Assembly Of Cab Assembly ................................................. 8-17

831 Disassembly of Cab Assembly .................................................................. 8-17

832 Assembly of Cab Assembly ...................................................................... 8-23

833 Replacement of Seat .................................................................................. 8-29

834 Disassembly and Assembly of Operation Box .......................................... 8-30

84 Disassembly and Assembly of Engine Hood .................................................... 8-32

841 Disassembly of Engine Hood .................................................................... 8-32

842 Assembly of Engine Hood ......................................................................... 8-35

85 Disassembly and Assembly of A/C System ...................................................... 8-39

851 Disassembly of Evaporator Assembly ...................................................... 8-39

852 Assembly of Evaporator Assembly ........................................................... 8-41

853 Replacement of Evaporator Components .................................................. 8-44

854 Replacement of Condenser Fan ................................................................. 8-51

855 Replacement of Receiver-drier .................................................................. 8-53

856 Replacement of Compressor Components ................................................ 8-54

857 Draining and Filling of Refrigerant ........................................................... 8-56

86 Common Faults Diagnosis and Troubleshooting for A/C System .................... 8-60

861 Regular Inspection Items ........................................................................... 8-60

862 Analysis of Cooling Failure ....................................................................... 8-61

863 Analysis of Insufficient Cooling ............................................................... 8-62

864 Analysis of Heating Failure ....................................................................... 8-62

865 Analysis of Other Faults ............................................................................ 8-62


8-1

8 Cab & Covering

Parts System

81 Overview of Cab

The G9165 cab is a specially designed grader cab by

SDLG.

811 Cab Exterior Description

1. The cab is designed with FOPS&ROPS

function. ROPS and FOPS are used to prevent

heavy, falling objects from causing injury to

the operator, and protecting operators in case

of a roll over. ROPS does not only support the

load when the machine is rolling over, but also

absorbs the impact energy as well.

2. The G9165 cab is fixed on the rear frame using

4 dampers, which decreases the external

vibration effectively so as to improve the ride

comfort.

1

Fig. 8-1

1 Cab

1

Fig. 8-2

1 Damper


8-2

3. The ROPS (Roll Over Protection System)

includes a heavy duty bolt (ROPS bolt) and a

permanently installed gasket (ROPS gasket).

The ROPS bolt is used to connect the cab and

frame. In the circumstance of rolling over, the

ROPS can prevent the cab from detaching the

machine.

ATTENTION

If they are damaged due to falling things or

machine rolling over, the intensity will

reduce, and they cannot satisfy the normal

protecting function. In this case, please

contact with Lingong Construction

Machinery Co., Ltd. or its designated

dealers to consult repair method. It is

definitely not allowed to repair it

arbitrarily.

The operators are protected effectively only

when they properly utilize the operator seat

safety belts. The operator must always use

the seat safety belt when operating the

machine. It is recommended that regular

inspection of the operator seat safety belt be

performed, and if any damage is found, the

operator seat safety belt must be replaced.

It is also recommended that the operator

seat safety belt be replaced every three

years, even if no damage is observed.

Never drill or weld inside or outside the

ROPS in order to avoid damaging or

reducing the effectiveness of the protective

structure.

WARNING

If “ROPS” structure is damaged due to

1 2

Fig. 8-3

1 ROPS bolt 2 ROPS gasket


8-3

plastic deformation or failure, then the

“ROPS” structure must be replaced

immediately, please contact with the nearest

SDLG designated dealer for support.

812 Cab Interior Description

The control handles and instrument panel are

located in front of cab, and the gear shift control

handle is on the right-hand side. Simple operation,

in line with people's operating habits.

1. Starting switch

This switch is used for starting or stopping

(shut-down) of the engine. The ON position is

also used to turn on the machine electrical

system.

a) PRE position

This position is used to turn on the engine

pre-heating cold start system.

b) OFF position

Insert or remove the key in this position.

Turn the key to this position to shut down

the engine.

c) ON position

This position is used to turn on the electric

system of the machine. The key will

remain in this position when the engine is

running.

d) ST position

This is the engine-start position. Turn the

key to this position to engage the engine

starting motor.

Once the engine is started, immediately

release the key to let it return to the ON

position by spring force.

1

Fig. 8-4

1 Starting switch


8-4

2. CD player/Radio control panel (Optional)

The control panel is located on the right part

on the cab ceiling, for operation method please

reference CD Player/Radio Control Panel

Operation Manual.

3. Gear shift control

Gear shift mechanism is electro-hydraulically

controlled, 6 forward gears on the left side and

3 backward gears on the right side. Besides,

negative control is available only when

transmission box is in gear I. When traveling

downhill, you should select a suitable gear to

keep the engine speed bigger than 1200r/min,

to guarantee lubrication of the machine.

ATTENTION

The gears should be selected successively, do

not skip any gears when shifting. Do not pull

or push the handle rashly and fiercely.

4. Rocker switches

Turn signal lamp switch and front

headlamp switch are located in the front of

cab, below the steering wheel.

1

Fig. 8-5

1 CD player

Fig. 8-6

1 2

Fig. 8-7

1 Turn signal lamp switch

2 Front headlamp switch


8-5

Warning light switch

Press down the bottom end, all the turning

signal lamps will be on, which is used for

emergency to send alarm signals warn the

passing pedestrian and vehicles. Press

down the top end, all the turning signal

lamps will be off.

The switch is located on the right-hand

side.

Working light switch

Press down the top end, only front

working lights on top of the cab will be on.

Press down the bottom end, both the front

and the rear working lights will be on.

When the switch is in middle position, the

lights will be off.

Shovel blade light switch

Press down the bottom end, the blade light

on the front frame and the light on bottom

of cab will not be on. Press down the top

end, they will be off.

Rear working light switch

Press down the bottom end, the rear

working light on the rear hood will be on.

Press down the top end, it will be off.

Backlight switch

Press the bottom end and backlight will be

on; Press the top end, it will be off.

1

Fig. 8-8

1 Warning light switch

1

Fig. 8-9

1 Working light switch

1

Fig. 8-10

1 Shovel blade light switch

1

Fig. 8-11

1 Rear working light switch

1

Fig. 8-12

1 Backlight switch


8-6

Mute switch

Press the bottom end of the switch, the

audible alarm will stop.

Locking cylinder switch

This switch is an auto-reset switch. Push

bottom end and the lock cylinder retracts,

release the switch the cylinder will stop

retracting and be fixed at current position.

Push top end and the locking cylinder

extends, release the switch the cylinder

will stop extending and be fixed in current

position.

Reserved position for fan heater switch

Press the bottom end of the switch, the fan

heater will start to work, Press the top end,

fan heater will stop.

Rotating beacon switch

The switch is located in right-top of cab.

Press down the bottom end of the switch,

and the beacon on the top of the cab will

be on. Press down the top end, the beacon

will go off.

1

Fig. 8-13

1 Mute switch

1

Fig. 8-14

1 Locking cylinder switch

1

Fig. 8-15

1 Reserved position for fan heater

switch

1

Fig. 8-16

1 Rotating beacon switch


8-7

Windshield washer switch

This switch is an auto-reset switch. Push

bottom end and the washer spray works on

the front windshield. Push top end and the

washer spray works on the rear windshield.

Release the switch, it will reset to original

position.

Front windshield wiper switch

Push bottom end of the switch and the

wiper begins to work. Push the top end of

the switch and the wiper stops working.

There are 2 positions between ON and

OFF that give two different working

speeds.

5. Temperature control switches

Fan control switch

System switch controls the speed of

evaporator fan. It is divided into high,

neutral, and low grade power so that you

can properly select wind, and start/stop

A/C.

Fresh air switch

Control the fresh air actuator and

circulation of inside and outside air.

Cooling change switch

Rotate the switch clockwise to start cooling

system and choose proper cooling

capacity.

Cooling

Start the engine.

1

Fig. 8-17

1 Windshield washer switch

1

Fig. 8-18

1 Front windshield wiper switch

1 2 3

Fig. 8-19

1 Fan control switch

2 Fresh air switch

3 Cooling change switch


8-8

Turn on the power/fan control switch and

turn the temperature switch to the

"COOL" position. A light should indicate

cooling system is operating.

Adjust the fan control to a desired speed.

When the cab temperature reaches a

desired level, adjust the temperature

switch counterclockwise until the light

goes out indicating that the cooling system

has cycled off. When the cab temperature

goes above the temperature switch setting,

the light will come on and the cooling

system is engaged until it reaches the

appropriate cab temperature setting.

Heating

First, set cooling change switch to "O" or

"OFF" position.

Start the engine and open the cab heat

exchanger water valves.

Set the fan control to the desired air flow.

6. Cab light switch

This switch is located in the center of cab light.

Push it to “ON” position, the cab light will be

on. Push it to “OFF” position to turn it off.

1

Fig. 8-20

1 Cab light switch


8-9

7. Parking brake control handle

This handle is located at left side of operator’s

seat. Pull it up to engage parking brake and put

it down to release the brake.

8. Cigarette lighter

Insert the lighter and press it down, it will be

locked automatically. At this point, electric

heating piece of the lighter is contacting the

lighter socket, and then it starts to heat heating

wire. When the wire is heated to red color, the

snap spring is subject to strong heat and begins

to shift form to pop up the lighter. Then you

can use the lighter to light the cigarette, and

insert it back after that.

9. Tilt angle of steering wheel adjusting handle

Adjusting angle of steering wheel is 19°.

Control the handle on the right side of

instrument desk to tilt the steering wheel to the

desired position.

Fig. 8-21

1

Fig. 8-22

1 Cigarette lighter

1

Fig. 8-23

1 Tilt angle of steering wheel

adjusting handle


8-10

10. Instrument desk inclination adjusting pedal

The instrument desk is locked by gas spring,

step the pedal to remove the lock, at this point,

the instrument desk can be tilted, hold the

steering wheel to adjust instrument desk to

desired position and release pedal to lock it.

Adjusting range is 70°~90°.

11. Steering wheel and horn button

The steering wheel and steering control unit

are connected. Turning the steering wheel

clockwise, the machine turns right, turning the

steering wheel counter-clockwise, the machine

turns left. Press the button in the middle of the

steering wheel and the horn will sound.

12. Safety hammer

In case of an emergency, the hammer hanged

in the left-rear side of the cab can be used to

break the window and flee the cab.

1

Fig. 8-24

1 Instrument desk inclination adjusting

pedal

1 2

Fig. 8-25

1 Horn button 2 Steering wheel

1

Fig. 8-26

1 Safety hammer


8-11

13. Working device control handles

As shown in the left figures, there are five

control handles on both sides of steel wheel,

which are used to control the two multitandem

valves on front of cab respectively, to perform

the following actions:

Up/down of shovel blade

Right and left lifting cylinder act on the

ball head on left and right side of

connecting rack respectively, by extending

or retracting the cylinder piston, the left

and right side of connecting rack can be

lifted or lowered, thereby height of the left

and right end of blade can be adjusted,

which can make the height and inclination

of the ground meet the requirements.

Shovel blade rotating

The rotary frame together with the blade

body can achieve 360° rotation in the

horizontal plane. A certain deflection

angle exists between blade and grader

travel direction, so that the scraped soil

can be discharged from the two sides and

the grader can work continuously.

Sidesway of shovel blade

Blades can extend to both sides along the

length of the blade under the action of the

sidesway cylinder so as to increase the

operation width of grader.

Side-swing of shovel blade

When the blades are fully extended to

both sides and the operation width is still

not enough, you can side-swing the

connecting rack, rotary frame and the

1 2

Fig. 8-27

1 From left to right, the handles are used

to control up/down of rear scarifier,

shovel blade tilt angle, hinge steering,

up/down of bulldozing plate

2 From left to right, the handles are used

to control up/down of left shovel blade,

sidesway of shovel blade, rotation of

shovel blade, swing of shovel blade, tilt

of front wheels, up/down of right shovel

blade


8-12

blades together left and right to increase

the operation range.

Side overturning of shovel blade

Side overturning of blade is used to scrape

side slope, under the joint action of left

and right lifting cylinder, the blades can

edge on left side and right side of grader

and form a certain angle to the ground, the

maximum side overturning angle of blade

is 90°.

Adjusting of shovel blade cutting angle

Under the action of blade tilt cylinder, the

blade body can tilt between forward 47°

and backward 5°, so as to get different

cutting angle of blade and to be used for

different working condition.

14. Operator’s seat

Weight adjustment

The weight adjustment handle is in the

front middle of the seat bottom area. Turn

the handle counterclockwise to reduce the

damping stiffness and turn the handle

clockwise to increase the damping

stiffness.

Fore-and-aft adjustment

The seat slide handle is on the front

bottom side of the seat. Pull the

fore-and-aft handle and move the seat

forward or backward to the desired

position. It will lock automatically after

releasing the handle.

Backrest angle adjustment

Pull the backrest angle adjustment handle

upward to release the backrest and allow

1 2 3

Fig. 8-28

1 Fore-and-aft adjustment handle

2 Weight adjustment handle

3 Backrest angle adjustment handle


8-13

for adjustment fore and aft until the

backrest angle is comfortable. The

backrest angle is locked by releasing the

handle.

Height adjustment

There are three positions for the height of

seat. The operator can adjust according to

the need. When adjusting, grasp the base

under the seat by two hands and pull it up,

and the seat will touch the clamp. When a

snap sound is heard, release the seat. The

seat will be fixed in this position. Adjust

the position of seat to the highest position,

and then press down. The seat will fall to

the lowest position.

Headrest height adjustment

Set the headrest of the seat by using two

hands. Pull up or push down to adjust the

height of the headrest.

15. Operator's seat safety belt

If there is safety belt, be sure to check it before

operation, and replace it if necessary. Please

fasten your seatbelts for your own safety

before operation.

16. Rear view mirrors

Rear view mirrors are located on the left and

right sides on top of the cab. Before starting

work, adjust the angle of the all rear view

mirrors for safe operation.

Fig. 8-29


8-14

82 A/C System Description

821 Function and Location of

Components

The grader A/C system is composed of compressor,

evaporator assembly, condenser assembly,

receiver-drier (fluid reservoir) and rubber cooling

hose. The compressor is driven through belt by the

grader engine. The panel switch controls the

temperature and air volume. Besides, it allows a

great quantity of air to get in and out, featuring

with a high efficiency of cooling and automatic

control of cab temperature.

1. The A/C compressor, just like the heart of the

A/C cooling system, maintains the refrigerant

circulation in the cooling system, by inhaling

low-temperature and low-pressure refrigerant

vapor from the evaporator, then compressing it

into high-temperature and high-pressure

refrigerant vapor, and finally delivering the

refrigerant vapor to condenser.

2. The condenser is a heat exchanger that held

together by pipes and cooling fins. Its function

is to cool and condense the high-temperature

and high-pressure refrigerant vapor into

high-pressure refrigerant liquid.

3. The receiver-drier is use to reserve refrigerant,

remove water from the refrigerant, filter

impurities and measure refrigerant quantity.

4. The function of expansion valve is to atomize

the liquid refrigerant from receiver-drier into

low-temperature, low-pressure and vaporous

refrigerant. It can also adjust the refrigerant

flow aquatically according to cooling load.

1 2

Fig. 8-31

1 Condenser

2 Receiver-drier

1

Fig. 8-30

1 Compressor


8-15

5. The evaporator is used to gasify the

low-temperature, low-pressure and vaporous

refrigerant by absorbing heat of the air in the

cab, so as to cool the cab. The cooling

performance of the A/C depends on heat

absorption capacity of the condenser.

822 System Description

This grader A/C system mainly consists of heater system, cooling system, ventilation system and

pressure control system.

This grader cooling system cools the air inside or fresh air from the outside to lower the temperature

in the grader.

The operating instructions are as follows:

1. Start the engine;

2. Turn on the fan control switch, then rotate the cooling change switch to “COOL”, and the

indicator lamp will be on, which indicates cooling is started;

3. Rotate the fan control switch, and you can select high, middle and low gears to enjoy three

different modes of air flowing;

4. When the temperature is down to the required temperature, anti-clockwise rotate the cooling

change switch slowly until the indicator lamp is off and the compressor stops running, in which

case, the temperature in the cab is the set temperature. With any higher internal temperature

than that, the indicator lamp will be on, the compressor will start automatically, and the system

will start cooling; and with any lower internal temperature than that, the indicator lamp will be

off, and the system will stop working;

5. When the A/C is turned on, dot rotate the cooling change switch to “COOL”, and rotate the fan

control switch to a low gear at the same time in case the evaporator frosts, which may affect the

cooling effect.

The grader heater system brings the coolant in the diesel engine into the heater radiator depending

on the heat of coolant, blows the heated air into the vehicle through a blower, and thus to increase

the internal temperature.

The heater system should be operated as follows:

Fig. 8-32


8-16

1. Rotate the cooling change switch to “O” or “OFF” position before use;

2. Start the engine and open the cab heat exchanger water valves;

3. Turn on the fan control switch, select the gear, and adjust to required air flow.

This grader ventilation system includes natural ventilation and forced ventilation. The natural

ventilation is the result of the air pressure outside while the grader is running; the forced ventilation

utilizes a blower to force fresh air outside into the cab.

This grader pressure system is controlled by a high/low-pressure switch, and in the event of

abnormal A/C system pressure including little or no refrigerant and excessively high pressure,

disconnect the compressor to protect the A/C system.

ATTENTION

Turn off the heat exchanger water valves when cooling in summer, and turn off the

cooling change switch when heating in winter.

Refrigerating fluid for A/C system of G9165 grader is R-134a (Freon-free environmental

refrigerant). It features high heat absorptivity, easy to liquefy, non-inflammable and non-explosive,

stable chemical contents, non-toxic and non-corrosive.

Fig. 8-33


8-17

83 Disassembly and Assembly Of

Cab Assembly

831 Disassembly of Cab Assembly

1. Before removal of cab, use a lifting rope to

hang the cab, hoist the cab properly until the

lifting rope is neither loose nor too tight.

2. Disconnect the connection between cab and

multitandem valve.

3. Disconnect the connection between steering

gear and cab.

Fig. 8-34

1

Fig. 8-35

1 Steering gear


8-18

4. Disconnect the connection between foot brake

valve and cab.

5. Disconnect the connection between A/C hoses

and evaporator.

ATTENTION

The refrigerant shall be drained firstly in

this procedure.

6. Disconnect the rear frame wire harnesses.

1

Fig. 8-36

1 Foot brake valve

Fig. 8-37

1

Fig. 8-38

1 Pull the yellow part upward, and then

unplug the connector


8-19

7. Disconnect the cab right-side wiring harnesses.

8. Disconnect the wiring harness under the hand

(parking) brake handle (on the bottom of cab).

9. Disconnect the windshield washer motor

wiring harness and the water pipe(s).

Fig. 8-39

1

Fig. 8-40

1 Wiring harness connector

Fig. 8-41


8-20

10. Disconnect the transmission control wiring

harnesses.

11. Disconnect the engine throttle control wire.

12. Disconnect the cab interior trim wiring

harness.

Fig. 8-42

1

Fig. 8-43

1 Engine throttle control wire

Fig. 8-44


8-21

13. Disconnect the fan heater water pipes.

14. Remove the rack(s).

15. Disconnect the hand (parking) brake.

Fig. 8-45

1

Fig. 8-46

1 Rack

Fig. 8-47


8-22

16. Remove the ROPS bolt.

17. Remove the cab (damper) fixing bolts.

18. Lift down the cab.

Fig. 8-48

1

Fig. 8-49

1 Fixing bolt

Fig. 8-50


8-23

832 Assembly of Cab Assembly

1. As shown, connect the lifting device, lift the

cab and put it onto the rear frame. Do not let

the cab hurt the pipeline of the rear frame.

ATTENTION

Hook the cab lifting eye with the lifting rope

to lift the cab horizontally and align it with

the mounting holes. Do not press down on

the hydraulic rubber hoses and wiring

harness connectors. Ensure that the cab is

smoothly lowered down in the course of

descending.

2. Install the cab (damper) fixing nuts.

3. Install the ROPS bolt.

Fig. 8-51

1

Fig. 8-52

1 Fixing nut

1

Fig. 8-53

1 Bolt


8-24

4. Connect the wiring harness under the hand

(parking) brake handle (on the bottom of cab).

5. Connect the windshield washer motor wiring

harness and the water pipe(s).

6. Connect the transmission control wiring

harnesses.

1

Fig. 8-54


Fig. 8-55

Fig. 8-56


8-25

7. Fix the multitandem valve on the support with

bolts.

8. Connect the lower connecting rods to the

multitandem valve orderly.

9. Connect the steering gear oil pipes.

Fig. 8-57

Fig. 8-58

1

Fig. 8-59

1 Steering gear


8-26

10. Connect the foot brake valve pipes.

11. Connect the rear frame wire harnesses.

12. Connect the cab interior trim wiring harness.

1

Fig. 8-60

1 Foot brake valve

1

Fig. 8-61


Fig. 8-62


8-27

13. Connect the cab right-side wiring harnesses.

14. Connect the A/C hoses to the evaporator.

15. Connect the fan heater water pipes.

Fig. 8-63

Fig. 8-65

Fig. 8-64


8-28

16. Connect the hand (parking) brake.

17. Connect the engine throttle control wire.

18. Install the rack(s).

Fig. 8-68

1

Fig. 8-67

1 Engine throttle control wire

Fig. 8-66


8-29

833 Replacement of Seat

1. Remove the bolts under the seat bracket.

2. Take the seat out of the cab.

3. Replace with new seat and install the bolts.

Fig. 8-69

Fig. 8-70

Fig. 8-71


8-30

834 Disassembly and Assembly of

Operation Box

1. Remove the cover plate fixing bolts.

2. Remove the shell plate fixing bolts.

3. Take down cover plate and shell plate.

4. Install cover plate and shell plate.

Fig. 8-72

Fig. 8-73

Fig. 8-74


8-31

5. Install the shell plate fixing bolts, but do not

tighten them.

6. Install the cover plate fixing bolts. Tighten all

the bolts.

Fig. 8-75

Fig. 8-76


8-32


Engine Hood

841 Disassembly of Engine Hood

1. Remove the rear cover side plate(s).

2. Disconnect the rear cover wiring harnesses.

3. Remove the connecting bolts of rear cover and

frame.

Fig. 8-77

1

Fig. 8-78


1

Fig. 8-79

1 Bolt


8-33

4. Remove the connecting bolts of engine hood

and rear cover.

5. Lift down the rear cover.

6. Remove the connecting bolts of engine hood

and expansion water tank.

1

Fig. 8-80

1 Bolt

Fig. 8-81

Fig. 8-82

1 Bolt

1


8-34

7. Remove the connecting bolts of air filter cover

and engine hood.

8. Remove the fixing bolts of hydraulic oil tank

cover plate on both sides.

9. Remove the link connecting bolts.

1 2

Fig. 8-83

1 Air filter cover

2 Bolt

1

Fig. 8-84

1 Cover plate

1 2

Fig. 8-85

1 Link 2 Bolt


8-35

10. Remove the power switch.

11. Remove the engine hood fixing bolts.

12. Lift down the engine hood.

842 Assembly of Engine Hood

1. Lift up the engine hood. Align the bolt holes

and put it down.

2. Install and tighten the engine hood fixing

bolts.

1

Fig. 8-86

1 Power switch

1

Fig. 8-87

1 Bolt

1

Fig. 8-88

1 Bolt


8-36

3. Install the power switch.

4. Fix the expansion water tank on engine hood

with bolts.

5. Fix air filter cover on engine hood with bolts.

1 2

Fig. 8-91

1 Air filter cover

2 Bolt

Fig. 8-90

1 Bolt

1

1

Fig. 8-89

1 Power switch


8-37

6. Install the link with bolts.

7. Lift and assemble hydraulic oil tank cover

plate(s), tighten the fixing bolts.

8. Lift and assemble rear cover, tighten the fixing

bolts.

1 2

Fig. 8-92

1 Link 2 Bolt

Fig. 8-94

1

Fig. 8-93

1 Cover plate


8-38

9. Connect the wiring harnesses.

10. Install the rear cover side plate(s).

1

Fig. 8-95


1

Fig. 8-96

1 Side plate


8-39


A/C System

Start the engine and drive the grader to smooth and

spacious ground. Fix the front of the front tires and

back of the rear tires with blocks. Keep the bucket

flat on the ground, and shut down the engine.

851 Disassembly of Evaporator

Assembly

1. Drain engine coolant (about 28L), contain it

with clean vessel.

2. Open the lockpin of the A/C hood assembly.

ATTENTION

Avoid directly contacting the refrigerant.

The removal and refitting of the climate

unit shall be conducted in a well-ventilated

area.

3. Remove the filters.

1

Fig. 8-97

1 Lockpin

1 2

Fig. 8-98

1 Fresh air filter module

2 Return air filter module


8-40

4. Disconnect the wiring harness connector of the

temperature control panel and fresh air door

motor.

5. Disconnect the evaporator-control panel

wiring harness connector and the evaporator

power wiring harness connector.

6. Disconnect the hose clamps of engine fan

heater water pipes.

7. Remove the connecting bolts of the evaporator

and cab.

1 2

Fig. 8-99

1 Filter cap

2 Air door wiring harness

1 2 3

Fig. 8-100

1 Power wiring harness connector

2 Evaporator-control panel wiring harness

connector

3 Temperature control panel

1 2

Fig. 8-101

1 Hose clamp 2 Bolt


8-41

8. Remove the 2 connecting bolts of cab interior

trim panel and evaporator assembly.

9. Take down the evaporator assembly and put it

in suitable place.

852 Assembly of Evaporator

Assembly

1. Install the evaporator assembly.

2. Connect the rubber hoses at the air vent of the

evaporator and air inlet of the cab.

ATTENTION

Keep the air vent and air inlet

unobstructed.

1 2

Fig. 8-102

1 Interior trim panel

2 Bolt hole

1

Fig. 8-103

1 Evaporator assembly

1

Fig. 8-104

1 Evaporator assembly


8-42

3. Install the hose clamps of engine fan heater

water pipes.

4. Install the connecting bolts of the evaporator

and cab.

5. Disconnect the evaporator-control panel

wiring harness connector.

6. Connect the evaporator power wiring harness

connector.

7. Install the 2 connecting bolts of cab interior

trim panel and evaporator assembly.

1 2

Fig. 8-105

1 Hose clamp 2 Bolt

1 2

Fig. 8-107

1 Interior trim panel

2 Bolt hole

1 2 3

Fig. 8-106

1 Power wiring harness connector

2 Evaporator-control panel wiring harness

connector

3 Temperature control panel


8-43

8. Connect the wiring harness connector of the


motor.

9. Install the filter cap.

10. Close the lockpin of the A/C hood assembly.

11. Fill refrigerant.

12. Recover the machine.

1 2

Fig. 8-108

1 Filter cap


1

Fig. 8-109

1 Lockpin


8-44

853 Replacement of Evaporator

Components

ATTENTION

The evaporator parts to be replaced should

be supplied with the same model and by the

same manufacturer, and do self-inspect to

make sure whether the replaceable parts

meet all the technical requirements.

Considering that there is nitrogen in the

A/C components and the system should be

free from impurities and moisture, connect

the pipeline immediately once you take off

the cap. If the pipeline is open, cover the

spout plug, or wrap it with a multilayer

plastic cloth instead.

Replacement of heater core

1. Remove the evaporator assembly from the

grader, and put it on a platform.

2. Remove the fixing plate installed on the right

side of the evaporator.

3. Remove all the clamps, and dismantle the

housing.

1 2

Fig. 8-110

1 Evaporator 2 Fixing plate

1

Fig. 8-111

1 Clamp


8-45

4. Take out the heater core and replace it.

5. Refit the housing, and fix all the clamps.

ATTENTION

Check whether the fan has been installed in

the right place.

6. Refit the heating system.

Replacement of blower






housing.

1

Fig. 8-112

1 Heater core

1 2

Fig. 8-113


1

Fig. 8-114

1 Clamp


8-46

4. Disconnect the wiring harness connector, take

out the blower and replace it.

5. Refit the housing, and fix all the clamps.

ATTENTION

Check whether the fan has been installed in

a right place.

6. Refit the heating system.

Replacement of expansion valve

WARNING

Please wear protective gloves to avoid

getting hurt by the oil.

1. Completely drain the refrigerant out from the

system.

2. Remove the filter and filter cap. Disconnect

the wiring harness connector of the


motor.

3. Remove the fixing plate on the right upper side

of the evaporator. Disconnect the pressure

sensor connector.

1

Fig. 8-115

1 Blower

1 2

Fig. 8-116

1 Filter cap


1 2

Fig. 8-117

1 Fixing plate

2 Pressure sensor connector


8-47

4. Disconnect the pipes from the expansion valve,

and remove the expansion valve. Block the

joint.

5. Take down the plug and install a new

expansion valve.

ATTENTION

Make sure the inner cavity of the expansion

valve is clean, and lubricate the sealing ring

with compressor oil.

6. Connect the expansion valve pipes.

7. Connect the pressure sensor connector.

8. Install the fixing plate.

9. Fill the refrigerant into the system with a

vacuum pump.

10. Install the filter cap. Connect the wiring

harness connector of the temperature control

panel and fresh air door motor.

11. Recover the grader.

1

Fig. 8-118

1 Expansion valve

1 2

Fig. 8-119

1 Fixing plate

2 Pressure sensor connector

1 2

Fig. 8-120

1 Filter cap



8-48

Replacement of temperature sensor






housing.

4. Pull out the temperature sensor joint, which is

located between the heater core and

refrigerator core. Replace the sensor with new

one.

1 2

Fig. 8-121


1

Fig. 8-122

1 Clamp

1 2

Fig. 8-123

1 Heater core 2 Refrigerator core


8-49

5. Refit the evaporator housing and install the

fixing plate.




7. Close the lockpin of the A/C hood assembly.


Replacement of evaporator

WARNING

Please wear protective gloves to avoid

getting hurt by the oil.

1. Open the cover of evaporator assembly.

2. Completely drain the refrigerant out from the

system.

3. Remove the filter and filter cap.

4. Disconnect the wiring harness connector of the


motor.

1

Fig. 8-124

1 Fixing plate

1 2

Fig. 8-125

1 Filter cap


1 2

Fig. 8-126

1 Filter cap



8-50

5. Remove the fixing plate on the right upper side

of the evaporator.

6. Disconnect the pressure sensor connector.


housing. Take out the evaporator and put it

aside.

8. Loosen the bolts and install the new

evaporator.

ATTENTION

Make sure the inner cavity of the

evaporator is clean, and lubricate the

sealing ring with compressor oil.

9. Connect the pressure sensor connector.

10. Assemble the evaporator housing.

11. Install the fixing plate.

1 2

Fig. 8-127

1 Fixing plate

1 2

Fig. 8-129

1 Fixing plate

1

Fig. 8-128

1 Evaporator


8-51




13. Fill the refrigerant into the system with a

vacuum pump.


854 Replacement of Condenser Fan

1. Remove the peripheral bolts of condenser

cover.

2. Unplug the plug of fan motor, remove

condenser cover and fan and put them on

cushion.

1 2

Fig. 8-130

1 Filter cap


1

Fig. 8-131

1 Filing hose

1

Fig. 8-132

1 Bolt


8-52

3. Loose the 4 connecting bolts of condenser fan.

ATTENTION

Pay attention to the nuts inside.

4. After replacing with a new fan, fasten the four

connecting bolts.

ATTENTION

When assembling the new fan, put the fan

wiring harness on the upper right position.

5. Assemble condenser cover and fan to the

condenser.

6. Recover machine.

1 2

Fig. 8-133

1 Condenser fan bolt

2 Fan wiring harness


8-53

855 Replacement of Receiver-drier

1. Drain the refrigerant.

2. Remove the steam storage pipe that connected

with the receiver-drier. Protecting the steam

storage pipe connector well is required.

3. Remove the upper bolts that connecting

condenser and receiver-drier. Protecting the

condenser pipe connector well is required.

4. Remove the bottom bolts that connecting

condenser and condenser pipe. Protecting the

condenser pipe connector well is required.

5. Loose the fixing bolts connecting

receiver-drier support and condenser. Remove

the receiver-drier.

6. Replace with a new receiver-drier and connect

it with steam storage pipe and condenser pipe.

Before connecting pipes, it is forbidden to

remove the plug cap. It can only be opened in

the last stage of installation.

7. Install the receiver-drier fixing bolts.

8. Fill refrigerant.

9. Recover the machine and check A/C system.

1 2 3

Fig. 8-134

1 Steam storage pipe

2 Receiver-drier

3 Condenser pipe

1 2

Fig. 8-135

1 Fixing bolt of receiver-drier support

2 Condenser pipe


8-54

856 Replacement of Compressor

Components

ATTENTION

The evaporator parts to be replaced should

be supplied with the same model and by the

same manufacturer, and do self-inspection

to check whether the replaceable parts meet

all the technical requirements.

Considering that there is nitrogen in each

A/C components and the system should be

free from impurities and moisture, connect

the pipeline immediately once you take off

the cap. If the pipeline is open, cover the

spout plug, or wrap it with a multilayer

plastic cloth instead.

Replacement of compressor belt

1. Put the machine in the maintenance position.

2. Open the engine hood.

3. Loose the connecting bolts and adjusting

screws, and then remove the belt.

4. Install a new belt, adjust the tension, tighten

and adjust the belt properly with the

connecting bolt. If the belt goes down for

10-12mm after being applied with the force of

about 10kg, the belt is adjusted properly. After

that, tighten the compressor.

5. Recover the machine and test-run the A/C

system.

1 2

Fig. 8-136

1 Belt 2 Adjusting screw


8-55

Replacement of compressor

1. Open the engine hood.

2. Drain the refrigerant completely out of the

system.

3. Release the belt tension, and remove the belt.

Pull out the clutch wiring harness plug.

4. Separate the compressor to condenser pipe and

evaporator to compressor pipe from the

compressor, put them aside for fixation, and

protect the condenser pipe connector well.

5. Loose and remove the fixing bolts of

compressor, then take down the compressor.

6. Drain the compressor oil into a calibrated

breaker (volume of the breaker should be no

less than 250ml).

ATTENTION

Pay attention to compressor oil.

The leaked compressor oil should disposed

in an environmentally friendly way

7. Replace the compressor with a new one

(pre-filled with 240ml compressor oil). Drain

the compressor oil completely out of the new

compressor.

8. Fill the old compressor oil (obtained by step 6)

into the new compressor.

9. Install the new compressor with the connecting

bolt, yet without tightening.

10. Pull off the plugs from the refrigerant pipe and

compressor, install the refrigerant pipe and a

new O-ring on the compressor, and lubricate

the O-ring with compressor oil.

11. Insert the connector, and install the refrigerant

pipe clamp.

1

Fig. 8-138

1 Belt

1 2

Fig. 8-137

1 Compressor to condenser pipe

2 Evaporator to compressor pipe


8-56

12. Refit the belt onto the compressor, adjust the

compressor location so that the compressor

clutch belt groove and the engine belt groove

are on the same plane, and then adjust the belt

moderately.

13. Add the refrigerant into the A/C system again.


857 Draining and Filling of

Refrigerant

Refrigerant draining

Instruments:

Refrigerant device Vacuum pump

Adaptor AC leak detector

Hose Platform scale

1. Put the refrigerant container on the platform

scale.

Make sure the volume of the refrigerant

container is big enough to contain the

refrigerant.

Weight the refrigerant, weight of refrigerant =

weight of refrigerant and container – weight of

refrigerant container.

Read the capacity of container from the

container.

2. Make sure there is no pressure in the recovery

device.

3. Connect the red “draining” hose of the

recovery device to the refrigerant container.

1

Fig 8-140

1 Drain hose

1

Fig. 8-139

1 Filling hose


8-57

Connect blue “absorption” hose to low

pressure connector of the machine.

Drain

4. Open the red hose valve on the refrigerant

container.

Open the valve on the refrigerant container.

Open the “draining” valve on the recovery

device.

Rotate the central controller to recovery

position.

Start the recovery device through the switch,

start draining.

Open the blue hose valve through the lower


Open “absorption” valve

5. When the weight no longer increases, check

whether the pressure is lower than the vacuum

degree displayed on the pressure gauge.

6. Close the absorption valve.

Close the blue hose valve through the low


Rotate the central controller to “auto clean”;

the blue pressure gauge falls to vacuum degree

again.

Close the recovery device.

Close refrigerant container valve.

Close draining valve.

7. Disconnect the recovery device from the

machine.

Fig 8-141

1 Scale displayer 2 Absorption

3 Central controller 4 Draining

5 Refrigerant container valve

6 Red hose valve

7 Refrigerant container

8 Platform scale


8-58

Refrigerant filling, including vacuum

pumping

Vacuum exhaust

1. Close all of the valves on the pressure gauge

box.

2. Connect the red hose to the high pressure

connector on the machine.

Open the hose valve through the machine

connector.

3. Connect the blue hose to the low pressure

connector on the machine.

Open the hose valve through the machine

connector.

4. Connect the yellow hose to the refrigerant

container.

Place the refrigerant container upside down on

the platform scale.

Check whether there is refrigerant in the

container. Weight of refrigerant = weight of

refrigerant and container – weight of

refrigerant container.

5. Open the two green valves on the pressure

gauge box.

Start the vacuum pump.

6. Open the blue and red valves on the pressure

gauge box.

Start the vacuum gauge.

Keep the vacuum pump working at least for 50

minutes.

7. When reached the right pressure, close the two

green valves, red valve and blue one on the

pressure gauge box.

Close the vacuum pump.

1 2

Fig 8-142

1 Red hose 2 Blue hose

2 3 4

Fig 8-143 Pressure gauge box

1 Vacuum gauge

2 Refrigerant container

3 Platform Scale

4 Vacuum pump


8-59

Disconnect the hoses from the machine.

Filling

8. Connect the adaptor to the low pressure

connector of the machine, and fill in the same

volume of oil consumed by system.

Remove the adaptor.

9. Connect the red hose to the high pressure

connector of the machine.

Connect the blue hose to the low pressure

connector of the machine.

10. Press the TARA (reset the scale) on the scale

displayer.

Open the yellow valve on the pressure gauge

box.

11. Open the blue valve, start filling.

12. Under the condition of opening AC power,

start the engine. Run the engine at the speed of

1000rpm.

13. When the platform scale shows the right

weight of the refrigerant, close the refrigerant

valve (refer to the information on the inside of

the machine hatch).

Close the yellow valve on the pressure gauge

box.

14. Close the hose valve through the machine

connector.

Close all of the valves on the pressure gauge

box.

15. Open the red and blue valves through the

machine connectors and check the pressure at

the speed of 1800rpm.

16. Disconnect the red and blue hoses from the

machine.

1 2

Fig 8-145

1 Red hose 2 Blue hose

1

Fig 8-144

1 Adapter


8-60

86 Common Faults Diagnosis and Troubleshooting for A/C System

To inspect faults and troubleshoot the A/C system, determine the cause of malfunction definitely

according to the abnormal phenomenon of A/C running, and then take measures. The common

faults of A/C system include system cooling failure, insufficient cooling capacity, heating failure

and etc.

861 Regular Inspection Items

The grader A/C system which works in a rather severe environment may be damaged regardless of

whether it is working or not, so it's better to enhance the routine maintenance.

Frequently inspect all the pipeline connects of A/C system, the compressor fixing bracket and the

compressor belt which should be tensioned properly, observe the cooling system hoses which

should be free of wear, inspect the A/C system wiring harness, and keep condenser surface clean.

Table 8-1 Table of regular inspection items

Inspection items Inspection content Interval

Daily Half a year Yearly

Pipeline assembly

Poor fastness, with gap. ▲ ▲

Loose connection, looseness of nut

and bolt. ▲ ▲

Connecting bolt Loose connection, looseness and

falling off of nut and bolt. ▲ ▲

Belt

Looseness and bend. ▲ ▲

Degradation, wear, bruise and

cracking. ▲ ▲

Noise, off-flavor or abnormal

heating. ▲

Condenser

assembly

Cooling fin falls down. ▲

Foreign materials clogging. ▲ ▲ ▲

A/C fan control

switch

Start inspection, air volume and

switch control. ▲ ▲

Change-over function. ▲ ▲

Refrigerant

leakage

Leakage in pipeline joints. ▲ ▲

Leakage inside the components. ▲


8-61

Refrigerant

quantity Inspect the refrigerant quantity. ▲ ▲

Noise

Compressor. ▲

Condenser blower and evaporator

blower. ▲

Temperature

difference of

receiver-drier

Surfaces that have temperature

difference are interfered with

foreign materials.

▲

862 Analysis of Cooling Failure

Table 8-2 Analysis table of cooling failure

Cooling

failure

The evaporator

blower runs.

The condenser

blower fails to

run.

The compressor

fails to work.

Inspect whether the blower

connector falls off, the ground is

normal, and the blower gets

damaged.

The compressor

works.

Inspect whether the temperature

control switch gets damaged, the

relay pulls in, the relay connector

is loose.

The condenser

blower runs.

The compressor

fails to work.

Inspect whether the clutch is

damaged, the connector falls off,

and the belt is loose or slips.

The evaporator

blower fails to

run.

The condenser

blower runs, and

the compressor

works as well.

Test whether the speed control switch malfunctions,

the blower wire is disconnected, and the blower

ground wire in good condition.

The condenser

blower fails to

run, neither the

compressor.

Test whether the fuses are blown and the relay works

normally, and inspect connecting wiring harness for

looseness.

The compressor

is normal.

Both the

evaporator blower

and condenser

blower work

normally.

If the machine is not occupied for a long term,

R134a leakage occurs, inspect with a pressure

gauge, and confirm whether there is R134a.


8-62

863 Analysis of Insufficient Cooling

Table 8-3 Analysis table of insufficient cooling

Insufficient

cooling

capacity

The

compressor

is normal.

Both the evaporator

blower and condenser

blower work normally,

so do the evaporator

and condenser.

The liquid receiver inlet and outlet are

reversely connected.

Inspect whether the expansion valve is

blocked by ice or dirt, and replace the liquid

receiver.

Replace the R134a.

The blower runs

normally, so do the

others.

Inspect whether the condenser surface has

been blocked by the incrustation

accumulated.

864 Analysis of Heating Failure

Table 8-4 Analysis table of heating failure

Heating

failure

The evaporator blower

runs normally.

Inspect whether the solenoid valve pulls in.

Inspect whether the other valves of heater pipeline are not

switched on yet.

The evaporator blower

fails to work.

Inspect whether the speed control switch malfunctions, the

blower wire is disconnected, and the blower ground wire

in good condition. Inspect whether the fuse is blown and

connecting wiring harness is loose.

865 Analysis of Other Faults

Table 8-5 Analysis table of other faults

S/N Symptoms Causes Troubleshooting

1

The system performs cooling normally

at the beginning, and the insufficient

cooling capacity occurs after a while;

bubble can be observed from the sight

glass of liquid receiver; the high/low

pressure gauge “readings” are low.

Mostly driving on the

rough road, the vibration

results in connector

looseness and then

leaking occurs.

Detect the leak with a

leak detector, and

screw up the loose parts

carefully.

2

The system fails to carry out cooling,

with hot air from the vent, and no

temperature difference between the

expansion valve inlet and outlet after

testing by hand, and the low pressure

gauge “readings” are low.

Improper operation may

be the cause. The

expansion valve thermal

bulb is worn and leaking,

which turns off the

valve.

Replace the expansion

valve, and renew the

R134a.


8-63

3

The air out of the vent is not cool, and

the compressor temperature increases.

The low pressure gauge pointer goes

down rapidly, and gets close to “0”,

while the high pressure gauge reading

remains high.

Impurities get into the

system, and block the

expansion valve strainer,

resulting in thin frost and

“perspiring” on the

expansion valve.

Intermittently starting

the cooling system may

resolve the instant

problem when the

blockage is not serious.

Or remove the

expansion valve and

clean it with alcohol

and renew the R134a

for the draining system.

4

The cooling capacity is insufficient, so

that the evaporator gets frosted; the

high/low pressure gauge “readings”

are low.

The orifice in the

expansion valve makes

no difference.

Drain the system,

replace the expansion


R134a.

5

After the system runs for a while, the

cooling capacity decreases gradually,

the high pressure gauge reading goes

up and the low pressure gauge reading

is less than 0.4Mpa.

The drying agent in the

receiver is saturate, and

the expansion valve

throttle is clogged by ice.

Drain the system,

replace the expansion


R134a.

6

After the cooling system is turned on,

only air instead of cool air comes out,

with the high/low pressure gauge

unchanged.

The temperature control

switch is not connected

well or the compressor

electromagnetic clutch

coil is damaged.

Inspect whether the

temperature control

switch is damaged with

a multimeter; replace

the compressor

electromagnetic clutch.

7

The compressor electromagnetic

clutch acts frequently, the engaged

time is short, with poor cooling effect,

and the high/low pressure gauge

readings are normal.

The temperature control

switch is turned on with

small opening angle, so

that the compressor stops

running, resulting in

insufficient cooling

capacity.

Inspect the temperature

control switch, which

should be turned to the

maximum cooling

Precautions for troubleshooting cooling system:

1. While troubleshooting the system, wear protective glasses and protective mask as many as

possible so as to avoid any direct contact with the refrigerant, which may cause frostbite,

and once any large amount of refrigerant contacts the human body, please wash with cold

water immediately.

2. The cooling system should be repaired at a well-ventilated place because the refrigerant is

colorless, tasteless, and even leads to personnel suffocation due to anoxia.

3. The refrigerant exposed to open flame will produce toxic phosgene, so keep away from any


8-64

fire sources.

4. To avoid any risk of explosion, soldering or cleaning with hot steam is not allowed around

the A/C pipeline or its parts.

5. During the replacement of system parts, make sure that the system connectors and system

inner cavities are clean. Meanwhile, replenish the refrigerator oil in accordance with the

standards shown in the table 8-6.

Table 8-6 Refrigerant capacity

Part name Supplementary capacity/mL

Evaporator 40~50

Condenser 40~50

System connecting hoses 30~40

Receiver-drier 15~25

6. After replacement of A/C parts, the pipeline joints, while being connected, should be

tightened to the specified tightening torque, which is shown in the table 8-7.

Table 8-7 Tightening torque

Thread dimensions Tightening torque

5/8-18UNF, M16×1.5 16~20Nm

3/4-16 UNF, M22×1.5 20~25Nm

7/8-14 UNF, M24×1.5 30~35Nm

8cab & covering parts system_englisg-g9165

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