Sinoboom GTBZ26 User manual

GTBZ26&28J Service Manual
Service Manual
GTBZ26&GTBZ28J
© Copyright by Hunan Sinoboom Intelligent Equipment Co.,Ltd.
The third edition: December 2019

GTBZ26&28J Service Manual
Contents
Foreword Safety Notices for Maintenance......................................................................................... 1
A Overview................................................................................................................................. 1
B Safety of Hydraulic System.................................................................................................... 1
C Maintenance............................................................................................................................ 1
Chapter 1 Specification.......................................................................................................................3
1.1 Capacity.................................................................................................................................3
1.2 Tires.......................................................................................................................................3
1.3 Engine Parameters................................................................................................................ 3
1.4 Specification and Performance Parameters.......................................................................... 4
1.5 Action Speed......................................................................................................................... 4
1.6 Torque Requirements............................................................................................................ 5
1.7 Hydraulic Oil.........................................................................................................................5
1.8 Weight of Main Parts............................................................................................................ 5
1.9 Lubrication and Operator Maintenance................................................................................6
Chapter 2 Overview.......................................................................................................................... 12
2.1 Overview of Machine Preparation, Inspection and Maintenance...................................... 12
2.2 Maintenance and Guide...................................................................................................... 14
2.3 Lubrication and Information...............................................................................................16
2.4 Testing of Oil Cylinder Shift...............................................................................................17
2.5 Repair guidance for pin roll and composite bearing.......................................................... 18
2.6 Welding on Sinoboom equipment.......................................................................................18
Chapter 3 Underframe and Turntable............................................................................................... 23
3.1 Tires and Rims.................................................................................................................... 23
3.2 Removal of Drive Motor.....................................................................................................24
3.3 Removal of Reducer........................................................................................................... 24
3.4 Installation of Reducer........................................................................................................25
3.5 Components of the reducer................................................................................................. 25
3.6 Adjustment and Maintenance of Steering Mechanism.......................................................28
3.7 Floating Balance Device (Floating Configuration)............................................................ 29
3.8 Installation of Cushion Block (Non-floating Configuration).............................................31
3.9 Turntable Rotation Mechanism...........................................................................................31
3.11 Removal and Installation of Rotary Reducer....................................................................35
3.12 Engine............................................................................................................................... 40
Chapter 4 Boom and Working Platform........................................................................................... 43
4.1 Boom System...................................................................................................................... 43
4.2 Boom Structure................................................................................................................... 44
4.3 Boom Cleaning Standard.................................................................................................... 48
4.4 Wireropes............................................................................................................................ 48
4.5 Wirerope Break Detection Proximity Switch..................................................................... 51
Chapter 5 Hydraulic System............................................................................................................. 53
Chapter 6 Electrical System..............................................................................................................55

GTBZ26&28J Service Manual
Please contact us:
Website: www.sinoboom.com
E-mail: [email protected]
Service Tel: [phone]
Fax: [phone]
Address: No.128, East Jinzhou Avenue, Ningxiang High-tech Industrial Park, Changsha,
Hunan,China
Zip code: 410600
Trainslation Version
Hunan Sinoboom Intelligent Equipment Co., Ltd. All Rights Reserved
The third edition: December 2019

GTBZ26&28J Service Manual
1
Foreword Safety Notices for Maintenance
A Overview
This chapter includes basic safety notices that
must be abided by in the maintenance process
of aerial work platform. The maintenance
personnel must strictly follow safety warnings
and notices to prevent injury to themselves or
others or damage to the equipment.
Maintenance plan must be strictly
implemented during the maintenance to ensure
the machine operates safely.
The machine cannot be altered before the
authorities believe that it has the same
safety as the original equipment.
Relevant key points in the manual describe
specific notices that must be followed in the
maintenance process. In most cases, these
notices must be abided by during maintenance
of hydraulic system and large machine
components.
Safety of yourself and others shall be the first
consideration during equipment maintenance.
Be sure to always pay attention to weight. Do
not move heavy parts without assistance of
mechanical equipment. Weight cannot be put
at any unstable position. Adequate support
shall be ensured when a part of the equipment
is lifted.
As the machine manufacturer cannot
directly control site inspection and
maintenance process, safety of the
maintenance site shall be under the
responsibility of the machine
owner/operator.
B Safety of Hydraulic System
Hydraulic system of the machine works under
the pressure with extremely high risk.
Therefore, pressure of the system shall be
released as far as possible before demolishing
or removing a part of the system.
C Maintenance
Violation of safety regulations listed in the
chapter may lead to machine damage and
personal injury.
Make sure the replaced parts are the same
or similar to original parts.
Smoking is forbidden. Filling of oil is
forbidden in lightning and storm. Make
sure the oil tank cover is closed and
under safe status at all time.
Please remove all rings, watches and
ornaments during the maintenance.
During the maintenance, please do not
wear too long hair or loose garment or tie
that is likely to be twined on the
equipment.
Observe all warnings and notices on the
machine and in the service manual.
Wipe off oil, grease and water on the
standing surface and handrail.
It is a must to observe notices for
detection of hot-pressing coolant system.
Warning
Warning
Warning

GTBZ26&28J Service Manual
2
The lifting boom must be blocked or
fixed with sling or use main boom safety
support before operation under it.
Before adjustment, lubricate or maintain
other parts and turn off all power
switches.
Batteries shall be removed before
replacement of electronic elements.
Make sure all supporting equipment and
accessories are located at correct
positions.
Approved non-flammable cleaning agent
can be used only.

GTBZ26&28J Service Manual
3
Chapter 1 Specification
1.1 Capacity
Table 1-1 Capacity
Hydraulic oil tank
170L/45 gal
Fuel tank
160L/42.3 gal
Hydraulic system
270L/71.3 gal
1.2 Tires
Table 1-2 Specification of Tires
Tire specification
385/65-24/10
Tire diameter
1060mm/3.47ft
Tire width
360mm/1.18ft
Tire type
Solid, big pattern
Maximum load
10500kg/23149lb
Tire specification
385/65-24
Tire diameter
1095mm/3.6ft
Tire width
390/1.28ft
Tire type
Pouring type foam t
ire
Maximum load
9750lg/21495ft
1.3 Engine Parameters
Table 1-3 Cummins QFS2.8t3TC72
Specification
Type
Water-cooling
Number of cylinders
4
Cylinder diameter
94mm/3.7in
Stroke
100mm/3.9in
Total displacement
2.8L/0.74gal
Compression ratio
16.7
Ignition sequence
1-2-4-3
Output power
54KW@2200rpm
Torque
270N*m@1800rpm
Capacity
Cooling system
capacity
Engine oil capacity
3.5L/0.92gal
8L/2.1gal92
Low-speed
1500rpm
High-speed
2200rpm
Table 1-4 Deutz TD 2.9L4 Specification
Type
Water-cooling
Number of cylinders
4
Cylinder diameter
92mm/3.6in
Stroke
110mm/4.3in
Total displacement
2.9L/0.77gal
Compression ratio
17:1
Ignition sequence
1-2-4-3
Output power
55.4KW@2300rpm
Torque
260N*M@1800rpm
Capacity
Cooling system
capacity
Engine oil capacity
3.3L/0.87gal
8.9L/2.35gal
Low-speed
1500rpm
High-speed
2200rpm

GTBZ26&28J Service Manual
4
1.4 Specification and Performance
Parameters
Table 1-5 Operation Specification
Load of working
platform-GTBZ26
Unrestricted Load
restricted Load
250kg/551lb
480kg/1058lb
Load of working
platform-GTBZ28J
Unrestricted Load
250kg/551lb
Maximum height of
platform
GTBZ26
GTBZ28J
25.8m/84 ft 8 in
27.7m/90
ft 10.5 in
Maximum horizontal
extension
GTBZ26
GTBZ28J
20.4m/66 ft 11
20m/65 ft 7.5 in
Maximum driving speed
2WD
4WD
5.2km/h/3.2mph
(2WD)
4.4km/h/2.7mph
(4WD)
Gradeability
2WD
4WD
30% /17°(2WD)
45%/24°(4WD)
Turning radius
Inside
Outside
2.44m/8ft
5.84m/19.2ft
Turntable rotation
360°
Platform rotation
160°
Maximum allowable
wind speed
12.5m/s
28mph
Maximum allowable
inclination angle
5°
Maximum allowable
hand thrust
90lbf
400N
Table 1-6 Product Size
Retracted length
GTBZ26
11.54m/37 ft 10 in
GTBZ28J
13.22m/43ft
Retracted width
2.49m/8 ft 2 in
Retracted height
2.88m/9 ft 5 in
Ground clearance
0.41m/1 ft 4 in
Wheelbase
3m/9 ft 10 in
Control voltage
12V
Total weight
GTBZ26-2WD
GTBZ26-4WD
GTBZ28J-2WD
GTBZ28J-4WD
16442kg/36248lb( 2WD)
16532kg/36447lb (4WD)
16581kg/36555lb (2WD)
16671kg/36753lb (4WD)
1.5 Action Speed
Table 1-7 Action Speed (Unit S)
Action Item
GTBZ26
GTBZ28
J
Upward luffing
100-115
100-115
Downward luffing
90-105
90-105
Turntable rotation
-boom fully retracted
95-103
95-103
Turntable rotation
-boom outstretched
220-260
220-260
Boom outstretching
85-95
85-95
Boom retraction
75-85
75-85
Platform rotation
18-22
18-22
Jib boom up
/
28-32
Jib boom down
/
28-32
Maximum traveling
speed (30m)
20～25
20～25
Speed testing requirements
Luffing: the boom is fully retracted when
luffing down in place. Luff upward twice and
luff downward twice for the testing.
Turntable rotation: the boom is located at the
center. Rotate one circle and test twice..
Outstretching and retraction: when the
boom achieves the maximum luffing angle,
the boom is fully retracted. The boom
outstretches twice and retracts twice.
Traveling: the testing shall be performed on a
horizontal plane. Switch to high engine speed

GTBZ26&28J Service Manual
5
and high traveling speed status and push the
traveling handle to the maximum stroke. Drive
forward and backward by 30m for twice
respectively.
Platform rotation: when the working
platform is horizontal, rotate the platform
from the leftmost to the rightmost twice and
then rotate from the rightmost to the leftmost
twice.
Jib boom: with the platform horizontal,
starting from the lowest position of jib boom,
raise and lower the jib boom twice,
respectively.
Testing notices
1. When to start or finish are dependent on
actions instead of controller or switch.
2. The result of traveling testing varies with
different tire specifications.
3. All speed testing shall be performed on
the platform control box. Operation from
the ground control box will differ.
4. All testing shall be performed when
hydraulic oil temperature is higher than
38℃. Too low hydraulic oil temperature
will affect the result of testing.
1.6 Torque Requirements
Table 1-8 Torque Requirements
Name
Torque
Value
Time
Interval
Wheel bolt
800Nm
50/600*
Rotary support
bolt
580Nm
50/600*
Balance weight
bolt
730Nm
Decided
according to
situations
Engine bolt
120Nm
Decided
according to
situations
* Inspection should be performed after initial
operation of 50 hours, followed by every 600
hours for the sake of safety.
Note: please refer to the torque table for
maintenance or when fastener becomes loose
to decide the proper torque value.
1.7 Hydraulic Oil
Table 1-9 Specification of Hydraulic Oil
Range of Working
Temperature of
Hydraulic System
Common Hydraulic
Oil
-20℃ to 100℃
23#
-5℃ to 120℃
46#
10℃ to 130℃
68#
1.8 Weight of Main Parts
Table 1-10 Weight of Parts
Components
Weight (kg/lb)
Reducer and motor
135 kg /298 lb
Tire assembly
320 kg /705 lb
Engine-Cummins
448 kg /988 lb
Engine-Deutz
474 kg /1045 lb
Counterweight
4900 kg /10803 lb
Luffing oil cylinder
380 kg /838 lb
Jib boom
155 kg/341 lb
Working platform
207kg/456 lb
Slewing mechanism
376 kg /829 lb
Telescopic oil cylinder
364 kg /802 lb
Leveling oil cylinder
32 kg /71 lb
Chassis assembly
4090 kg /9017 lb
Slewing table
assembly
8000 kg /17637 lb
Boom assembly
3000 kg /6614 lb

GTBZ26&28J Service Manual
6
1.9 Lubrication and Operator
Maintenance
Lubrication intervals are all based on the
condition that the machine operates under
normal conditions. When equipment
operates in multi-shift manner or is exposed
to harsh environment, lubrication
frequency and lubricant amount shall be
increased accordingly.
1. Shaft lubrication
Lubrication point:
Capacity: decided as necessary
Lubricant: ZL-3 lithium grease
Interval: everyday or every 8 hours
2. Rotary support: remote lubrication
Lubrication point: 1 lubricating oil cup
Capacity: decided as necessary
Lubricant: ZL-3 lithium grease
Interval: every 3 months or 150 hours of
operation
3. Slewing reducer
Lubrication point: Fuel Feeding Plug
Capacity: 2L
Lubricant: industrial gear oil 90#
Interval: Check the oil level every 150
hours/Change the oil after running 1200
hours, and fill to submerge the inner ring.
4. Traveling reducer
Lubrication point: oil filler plug
Capacity: 0.68L/0.18gal
Lubricant: industrial gear oil 90#
Interval: check oil level after initial 50
hours, then replace lubricating oil after
initial use for 50-100 hours and later
replace lubricating oil after every 1000
hours or half a year.
Method: rotate the reducer to the
illustrated position, remove bolt 1 and
bolt 2, and fill gear oil from the hole of
bolt 1 until oil spills out of the hole of
bolt 2.
Notice

GTBZ26&28J Service Manual
7
5. Hydraulic Return Oil Filter
Maintenance point: replaceable element
Interval: replace first after 50 hours of
operation, and later after every 300
hours.
6. Hydraulic oil filter
Maintenance point: replaceable element
Interval: replace first after 50 hours of
operation, and later after every 300
hours.
7. Hydraulic oil
Lubrication point: filler cap
Capacity: 170L/45gal
Lubricant: hydraulic oil
Interval: check oil level after the boom is
lowered every day. Later replace oil after
every 2 years or 1200 hours of operation.
8. Suction oil filter (inside the oil tank)
Maintenance point: 2 locations in the oil
tank
Interval: every 2 years or 1200 hours of
operation. Clear and clean during
replacement of hydraulic oil.
9. Engine oil filter-Cummins

GTBZ26&28J Service Manual
8
Lubrication of maintenance point: oil
filler
Capacity: 4.5L/1.2gal
Lubricant: CH-4 level engine oil
Interval: check oil level every day.
Replace every 500 hours or 6 months of
operation, whichever comes first. Adjust
the final oil level on the oil level gauge.
10. Diesel filter-Cummins
Maintenance point: replaceable element
Interval: replace every 500 hours or 6
months of operation, whichever comes
first.
11. Oil-water separator-Cummins
Maintenance point: replaceable element
Interval: drain once every day. Replace
every 500 hours or 6 months, whichever
comes first.
12. Air filter -Cummins
Maintenance point: replaceable element
Interval: replace every 500 hours or 6
months of operation or replace according
to actual situations.
13. Oil Filter-Deutz

GTBZ26&28J Service Manual
9
Lubrication point: oil filler
Capacity: 4.5L/1.2gal
Lubricant: CH-4 level engine oil
Interval: check oil level every day.
Replace every 500 hours or 6 months of
operation, whichever comes first. Adjust
the final oil level on the oil level gauge.
14. Diesel Filter -Deutz
Maintenance point: replaceable element
Interval: replace every 500 hours or 6
months of operation, whichever comes
first.
15. Diesel Prefilter-Deutz
Maintenance point: replaceable element
Interval: drain once every day. Replace
every 500 hours or 6 months, whichever
comes first.
16. Air Filter-Deutz
Maintenance point: replaceable element
Interval: replace every 500 hours or 6
months of operation or replace according
to actual situations.

GTBZ26&28J Service Manual
10
Table 1-11 Fastening Torque of Thread Fasteners with Only Flat Gasket
Thread
Diameter
mm
Thread Pitch
mm
Fastening Torque (N.m)
Grade 8.8
Grade 10.9
Standard
Me
Minimum
Min
Maximum
Max
Standard
Me
Minimum
Min
Maximum
Max
8
Coarse thread
1.25
30
25
35
42
34
50
Fine thread
1
30
26
36
46
38
54
Coarse thread
1.5
58
48
68
85
70
100
10
Fine thread
1.25
60
50
70
90
75
100
1
65
55
75
95
80
110
12
Coarse thread
1.75
100
85
120
150
120
170
Fine thread
1.5
110
90
120
160
130
180
1.25
110
90
130
160
140
190
14
Coarse thread
2
160
130
190
240
200
280
Fine thread
1.5
170
140
200
260
210
300
16
Coarse thread
2
250
210
290
370
310
430
Fine thread
1.5
270
220
310
390
330
460
18
Coarse thread
2.5
360
300
420
510
420
590
Fine thread
1.5
400
330
470
570
480
670
20
Coarse thread
2.5
500
420
590
720
600
840
Fine thread
2
530
440
620
760
630
880
1.5
560
470
650
800
660
930
22
Coarse thread
2.5
690
570
800
980
810
1140
Fine thread
2
720
600
840
1030
860
1200
1.5
750
630
880
1070
900
1250
24
Coarse thread
3
870
730
1020
1240
1040
1450
Fine thread
2
950
790
1110
1350
1130
1580
27
Coarse thread
3
1280
1060
1490
1820
1510
2120
Fine thread
2
1380
1150
1610
1960
1640
2290
30
Coarse thread
3.5
1730
1440
2020
2470
2060
2880
Fine thread
2
1920
1600
2240
2730
2280
3190
33
Coarse thread
3.5
2360
1960
2750
3360
2800
3920
Fine thread
2
2590
2150
3020
3680
3070
4300
36
Coarse thread
4
3030
2520
3530
4310
3590
5030
Fine thread
3
3110
2670
3740
4570
3810
5330
Metric system grade 8.8 Metric system grade 10.9

GTBZ26&28J Service Manual
11
Table 1-12 Fastening Torque of Thread Fasteners with At Least Spring Washer
Thread
Diameter
mm
Thread Pitch
mm
Fastening Torque (N.m)
Grade 8.8
Grade 10.9
Standard
Me
Minimum
Min
Maximum
Max
Standard
Me
Minimum
Min
Maximum
Max
8
Coarse thread
1.25
25
20
30
38
32
44
Fine thread
1
28
25
32
40
34
46
Coarse thread
1.5
50
40
60
75
65
85
10
Fine thread
1.25
55
45
65
80
65
95
1
55
45
65
85
70
100
12
Coarse thread
1.75
90
75
105
130
110
150
Fine thread
1.5
95
80
110
140
120
160
1.25
98
80
115
140
120
170
14
Coarse thread
2
140
120
170
210
170
240
Fine thread
1.5
150
130
180
230
190
260
16
Coarse thread
2
220
180
260
330
270
380
Fine thread
1.5
240
200
280
350
290
400
18
Coarse thread
2.5
310
260
370
450
370
520
Fine thread
1.5
350
300
410
500
420
590
20
Coarse thread
2.5
450
370
520
630
530
740
Fine thread
2
470
390
550
670
560
780
1.5
500
410
580
700
590
820
22
Coarse thread
2.5
610
510
710
860
720
1010
Fine thread
2
640
530
740
910
760
1060
1.5
670
560
780
950
790
1110
24
Coarse thread
3
770
640
900
1100
920
1280
Fine thread
2
840
700
980
1200
1000
1400
27
Coarse thread
3
1130
940
1320
1610
1340
1880
Fine thread
2
1220
1020
1420
1740
1450
2030
30
Coarse thread
3.5
1530
1280
1790
2180
1820
2550
Fine thread
2
1700
1410
1980
2420
2010
2820
33
Coarse thread
3.5
2100
1740
2430
2970
2480
3470
Fine thread
2
2300
1910
2670
3260
2710
3800
36
Coarse thread
4
2680
2230
3130
3820
3180
4450
Fine thread
3
2840
2360
3310
4040
3370
4710
Metric system grade 8.8 Metric system grade 10.9

GTBZ26&28J Service Manual
12
Chapter 2 Overview
2.1 Overview of Machine Preparation,
Inspection and Maintenance
Overview
This chapter will provide necessary
information to operators who make the
machine ready and keep safe operation. All
necessary inspections and maintenances shall
be completed before the machine is put into
service in order to obtain the longest service
life and guarantee safe operation.
Preparation, Inspection and Maintenance
Comprehensive inspection and preventive
maintenance plan must be established and
observed. The following forms record regular
inspections and maintenances recommended
by SINOBOOM. Please refer to relevant
stipulations of your country, region or local
area to obtain more requirements regarding
aerial work platform. The frequency of
inspection and maintenance shall be increased
according to specific environment, strictness
and operating frequency.
Pre-operation Inspection
Users or operators shall first perform
pre-operation inspection before daily use or
every work shift. For detailed steps of
pre-operation inspection, please refer to the
operation manual. Please read carefully and
fully understand the Operation Manual.
Pre-delivery Inspection and Daily
Inspection
Pre-delivery inspection must be performed by
qualified SINOBOOM equipment engineers.
SINOBOOM equipment engineers recognized
by SINOBOOM shall have universally
accredited education background, certificate,
and rich knowledge and experience, accept
relevant trainings and boast the capacity and
qualification necessary for repair and
maintenance of SINOBOOM product model
stated in the instruction.
Pre-delivery inspection and daily inspection
are the same in inspection method but
different in inspection times. The pre-delivery
inspection must be performed before every
time delivery for selling, renting or leasing
products, while the daily inspection must be
performed when the equipment is used for 3
months or 150 hours (whichever comes first)
or put aside by more than 3 months or bought
as second-hand equipment. The frequency of
inspection shall be increased according to
specific environment, strictness and operating
frequency.
In the course of such inspections, please refer
to SINOBOOM Pre-delivery Inspection and
Daily Inspection Form and Preventive
Maintenance Schedule for items to be
inspected and refer to the manual to
understand repair and maintenance steps.
Annual Inspection
Annual inspection of the machine shall be
performed by factory certified maintenance
engineers within 13 months following the last
annual inspection. Only the persons who have
gone through the training of specific product
models by maintenance training school of
Hunan SINOBOOM can be recognized as

GTBZ26&28J Service Manual
13
Factory certified maintenance engineers. For
the inspection, please refer to Service Manual
and applicable SINOBOOM inspection forms.
In the course of the inspection, please refer to
Annual Inspection Form of SINOBOOM
Machine and Preventive Maintenance
Schedule for the items to be inspected, and
please refer to the manual for repair and
maintenance steps.
To acquire safety related reports, Hunan
SINOBOOM has to update ownership
information of each machine. Please tell
ownership information of the current machine
to Hunan SINOBOOM during each annual
inspection of the machine.
Preventive Maintenance
SINOBOOM equipment engineers shall
perform preventive maintenance as required.
SINOBOOM equipment engineers recognized
by Hunan SINOBOOM shall have universally
accredited education background, certificate,
and rich knowledge and experience, accept
relevant trainings and boast the capacity and
qualification necessary for repair and
maintenance of SINOBOOM product model
stated in the instruction.
Please refer to Preventive Maintenance
Schedule and the manual to understand repair
and maintenance steps. The frequency of
repair and maintenance shall be increased
according to specific environment, strictness
and operating frequency.

GTBZ26&28J Service Manual
14
Table 2-1 Inspection and Maintenance
Type
Frequency
Primary
Responsibility
Maintenance
Qualification
Reference
Pre-operatio
n inspection
Before daily use, or when the
operator is changed.
User or operator
User or operator
Operation manual
Pre-delivery
inspection
Before each sale, rent or lease.
Owner, agent or user
Equipment engineer
approved by
SINOBOOM
Service manual and
applicable
SINOBOOM
inspection form
Daily
inspection
Used for 3 months or 150 hours
(whichever comes first);
Or idle for more than 3 months;
Or the purchased equipment is
old.
Owner, agent or user
Equipment engineer
approved by
SINOBOOM
Service manual and
applicable
SINOBOOM
inspection form
Equipment
annual
inspection
Annual overhaul shall not be
more than 13 months compared
with the last inspection.
Owner, agent or user
Qualified
maintenance
technician
(recommended)
Service manual and
applicable
SINOBOOM
inspection form
Preventive
maintenance
Carried out according to the time
interval specified in the service
manual.
Owner, agent or user
Equipment engineer
approved by
SINOBOOM
Service manual
2.2 Maintenance and Guide
Overview
The following information assists you in using
and applying repair and maintenance
procedures contained in the instruction.
Safety and Operation Standard
Safety of yourself and others shall be the first
consideration during equipment maintenance.
Be sure to always pay attention to weight. Do
not move heavy parts without assistance of
mechanical equipment. Weight cannot be put
at any unstable position. Adequate support
shall be ensured when a part of the equipment
is lifted.
Cleaning
1. The most important thing to prolong
service life of the machine is to prevent
entry of dirt or impurities into the
machine. The machine has taken
preventive measures to prevent such
invasion. Protective plate, outer cover,
sealing and filter are used to keep supply
of air, fuel and engine oil clean. They
shall be timely maintained as required to
ensure the effects of protective measures.
2. When any air, fuel or engine oil pipeline
is connected, clear the neighboring area,
openings and joints. Once a pipeline or a
part ruptures, all openings shall be
covered at once to prevent entry of
foreign matters.
3. During repair or maintenance, check and
clean all the parts to ensure all passages
and openings are free of blockage. All
parts shall be covered to make sure they
are clean. All parts must be kept clean
before installation. New parts shall be
stored in containers before use.

GTBZ26&28J Service Manual
15
Removal and Installation of Parts
1. When mechanical assistance is required,
please use adjustable lifting device as far
as possible. All lifting tools (chains and
slings) must be parallel to one another
and vertical to the top of the lifted part as
far as possible.
2. To remove parts at a corner, please keep
in mind that bearing capacity of eyebolt
or similar bracket will lower when the
angle between support structure and part
is less than 90°.
3. If a part is hard to remove, please check
whether all nuts, bolts, cables, trays and
wirings are all removed and whether any
neighboring parts obstruct their removal.
Removal and Reinstallation of Parts
To remove or reinstall a part, please complete
each step in order. Please do not start
operation of another part before removal or
installation of a part is completed. Please
always double check your work to make sure
nothing is omitted. No adjustment can be
performed before appropriate approval is
obtained (except recommended adjustment).
Press-fit part
Please lubricate the meshing surface with
anti-sticking or molybdenum disulfide
compound before assembly of press-fit parts.
Bearing
1. The bearing removed must be covered to
avoid attachment of contaminant or
abrasive material. The bearing shall be
washed in incombustible cleaning agent
and dried. It can be cleaned with
compressed air but cannot be rotated.
2. Please scrap the bearing in case of dent,
scratch, or burn of bearing race and steel
ball (or roller).
3. If the bearing is repairable, it shall be
wrapped with clean paper (or wax paper)
after application of a layer of oil. Please
do not unpack reusable bearing or new
bearing before installation.
4. Please lubricate new bearing or
overhauled bearing before installation.
Please press the bearing into the holder or
inner hole. Please exert pressure to
outside bearing race. To install the
bearing onto the shaft, please exert
pressure to the inner race.
Washer
Check whether the hole on the washer can
align with opening of the accessory. To
fabricate the washer manually, use washer
material or inventory material with equivalent
material and thickness Please make sure
opening is made at a correct position;
otherwise, sealing failure of the washer may
cause severe destruction of the system.
Use of Bolts and Application of Torque
1. Please use bolts of proper length. If the
bolts are too long, the bolts can touch the
bottom before their heads are fastened
onto relevant parts. If the bolts are too
short, there will be inadequate thread part
for meshing and fixation of parts. During
replacement of the bolts, bolts in the
same or equivalent specification as the
original bolts can be used only.
2. In addition to torque requirements
specified in the instruction, standard
torque values shall be used for bolts,
studs and steel bolts after thermal
treatment according to the recommended
factory practices (refer to torque table in
Chapter 1).
Hydraulic Pipeline and Electrical Wiring
While unplugging or removing hydraulic
pipelines or electrical wires from the
equipment, the hydraulic pipelines and
electrical wires and their sockets shall be

GTBZ26&28J Service Manual
16
clearly marked to ensure they can be
reinstalled correctly.
Hydraulic System
1. Keep the hydraulic system clean. In case
of metallic or rubber particles in the
hydraulic system, please completely
discharge and flush the entire system at
once.
2. Parts shall be removed or reinstalled on a
clean operation surface. All metal parts
shall be cleaned with incombustible
cleaning agent. Parts shall be lubricated
as necessary for easy assembly.
Lubrication
Please lubricate relevant parts at the specified
interval and use lubricant of the amount, type
and grade recommended in the manual. If no
recommended lubricant is available, consult
local supplier for equivalent lubricant with the
specification compliant with or surpassing the
specification listed.
Battery
Batteries shall be washed with nonmetallic
brushes and sodium bicarbonate and water
solution and then washed with clean water.
Battery terminals shall be applied with
anti-corrosion compound after the batteries are
totally dry.
Lubrication and Maintenance
Refer to “Lubrication Table” in Chapter 1 for
parts and components to be lubricated and
maintained.
2.3 Lubrication and Information
Hydraulic System
1. Contaminants are the primary factors that
impair the hydraulic system. They can
invade through a multiple of manners, for
instance, improper use of hydraulic oil,
entry of moisture, lubricating grease,
metal chip, sealing element and sand
during maintenance or failure of
preheating of the system or leakage of
water inlet pipe of water pump, resulting
in cavitation.
2. Design and manufacturing tolerance
standard for working parts is extremely
strict. Therefore, even a little
contaminant or foreign matter entering
the system can cause wear or destruction
of parts and consequent operation fault.
Be sure to take preventive measures to
keep the hydraulic oil clean, including oil
in reserve. Filter of the hydraulic system
shall be checked, washed or replaced if
necessary at the interval specified in
Chapter 1 and checked for metal particles
at any time.
3. If hydraulic oil is turbid, it indicates it
contains too much water, which may
cause inorganic matters to grow and
result in oxidation or corrosion. In this
case, discharge and wash the system and
refill clean hydraulic oil.
4. Other hydraulic oil may not contain the
specified additive or may have different
viscosity. Therefore, please do not mix
products of different brands or of
different types. It is recommended to use
quality mineral oil with viscosity suitable
for operation environment of the
machine.
Note: metal particles may occur inside
hydraulic oil or filter of the new machine due
to wear of screen.
Hydraulic Oil
1. Please refer to recommended viscosity
scope in Chapter 1.
2. SINOBOOM recommends that SAE
viscosity be of 32 or 46.
3. In addition to the above, the only

GTBZ26&28J Service Manual
17
exception is to drain off the system and
refill.
Check and replace the filter element and
hydraulic oil
1. The filter element shall be replaced first
after 50 hours of initial operation and
later every 300 hours (unless otherwise
specified). To replace the hydraulic oil,
please use the hydraulic oil of the
specification compliant with or
surpassing specification stated in the
manual. If the product of the same type
as the original hydraulic oil is hardly
achieved, please consult local supplier
how to select proper products. Please do
not mix petroleum and synthetic oil.
SINOBOOM recommends the hydraulic
oil shall be replaced on a yearly basis.
2. Necessary measures must be taken to
keep the hydraulic oil clean. To pour
hydraulic oil from the original container
to another container, make sure possible
contaminants inside the container are
completely cleaned. After replacement of
system oil, mesh screen elements of the
filter must be cleaned and drum-type
filter element must be replaced.
3. After the equipment is switched off,
proper preventive maintenance measures
are to fully check all hydraulic parts,
pipelines and joints and perform
functional inspection of each system
before restart of the machine.
Lubrication Specification
The special lubricant recommended by the
part manufacturer shall be always the optimal
selection. However, multi-function grease
generally boasts the characteristics up to
requirements of single-function grease.
Regarding use of grease to maintain the spare
part, please consult local supplier if you have
any problems. Please refer to Chapter 1 for the
lubricant names.
2.4 Testing of Oil Cylinder Shift
Measure the maximum acceptable shift of oil
cylinder with the following method.
Platform Shift
Measure the shift from platform to ground.
With the main boom fully outstretched, the
platform under the rated load and power
switched off, the maximum allowable shift
within 10 minutes is 50cm. If the machine
cannot pass the testing, please perform
following operations.
Shift of Oil Cylinder
Table 2-2 Shift of Oil Cylinder
Diameter of oil
cylinder
(mm)
Maximum
Acceptable Shift
(In 10 min) (mm)
63
0.96
80
0.63
100
0.39
125
0.23
160
0.14
180
0.13
200
0.10
220
0.08
The shift shall be measured with calibrated
micrometer at the place of oil cylinder piston
rod. Oil inside the oil cylinder shall be at
ambient temperature and stable temperature.
The oil cylinder must have normal load,
normal platform load exerted by the platform.
The oil cylinder is acceptable if it passes the
testing.
Note: the information is based on leakage of
oil cylinder is 6 drops per minute. As the
hydraulic oil features the physical
characteristics of the thermal expansion and
cold shrinkage, the tested results may have an
error of 7/10000.