Terex Genie GR-20J User manual

Service Manual
Serial Number Range
GR™-20J
from GRJL-2298
GR™-26J
Original
Instructions
Part No. 1312899GT
Rev A
March 2022

Service Manual March 2022
Introduction
ii GR™-20J • GR™-26J Part No. 1312899GT
Intro ductio n Intro ductio n
Importan t Inf or matio n
Important
Read, understand and obey the safety rules and
operating instructions in the appropriate Operator's
Manual on your machine before attempting any
maintenance procedure.
This manual provides detailed scheduled
maintenance information for the machine owner
and user. It also provides troubleshooting and
repair procedures for qualified service
professionals.
Basic mechanical, hydraulic and electrical skills
are required to perform most procedures.
However, several procedures require specialized
skills, tools, lifting equipment and a suitable
workshop. In these instances, we strongly
recommend that maintenance and repair be
performed at an authorized Genie dealer service
center.
Compliance
Machine Classification
Group B/Type 3 as defined by ISO 16368
Machine Design Life
Unrestricted with proper operation, inspection and
scheduled maintenance.
Technical Publications
Genie has endeavored to deliver the highest
degree of accuracy possible. However, continuous
improvement of our products is a Genie policy.
Therefore, product specifications are subject to
change without notice.
Readers are encouraged to notify Genie of errors
and send in suggestions for improvement. All
communications will be carefully considered for
future printings of this and all other manuals.
Contact Us:
Internet: www.genielift.com
E-mail: [e-mail]
Copyright © 2011 by Terex Corporation
1312899GT Rev A, March 2022
Second Edition, First Printing
Genie is a registered trademark of Terex South Dakota, Inc. in
the U.S.A. and many other countries.
“GR” is a trademark of Terex South Dakota, Inc.

March 2022 Service Manual
Introduction
Part No. 1312899GT GR™-20J • GR™-26J iii
RevisionHistory
Revision History
Revision Date Section Procedure / Page / Description
A 3/2022 Initial Release
Reference Examples:
Section – Maintenance, B-3
Electronic Version
Click on any content or procedure in the Table of Contents to view
the update.
Section – Repair Procedure, 4-2
Section – Fault Codes, All charts
Section – Schematics, Legends and schematics

Service Manual March 2022
Introduction
iv GR™-20J • GR™-26J Part No. 1312899GT
Serial Number Legend
1 Model
2 Facility code
3 Sequence number
4 Serial label
5 Serial number (stamped on chassis)

March 2022 Service Manual
Safety Rules
Part No. 1312899GT GR™-20J • GR™-26J v
Sec ti on 1 Safety Rul es
Gene ral Saf ety Rul es
Danger
Failure to obey the instructions and safety
rules in this manual and the appropriate
Operator's Manual on your machine will result
in death or serious injury.
Many of the hazards identified in the
operator's manual are also safety hazards
when maintenance and repair procedures are
performed.
Do not modify or alter a MEWP without prior
written permission from the manufacturer.
Do Not Perform Maintenance
Unless:
You are trained and qualified to perform
maintenance on this machine.
You read, understand and obey:
•manufacturer's instructions and safety
rules
•employer's safety rules and worksite
regulations
•applicable governmental regulations
You have the appropriate tools, lifting
equipment and a suitable workshop.

Service Manual March 2022
Safety Rules
vi GR™-20J • GR™-26J Part No. 1312899GT
Personal Safety
Any person working on or around a machine
must be aware of all known safety hazards.
Personal safety and the continued safe
operation of the machine should be your top
priority.
Read each procedure thoroughly. This
manual and the decals on the
machine, use signal
words to identify
the following:
Safety alert symbol
—used to
alert personnel to potential
personal injury hazards. Obey
all safety messages that follow
this symbol to avoid possible
injury or death.
Indicates a imminently
hazardous situation
which, if
not avoided, will result in death
or serious injury.
Indicates a potentially
hazardous situation which, if
not avoided, could result in
death or serious injury.
Indicates a potentially
hazardous situation which, if
not avoided, may cause mi
nor
or moderate injury.
Indicates a potentially
hazardous situation which, if
not avoided, may result in
property damage.
Be sure to wear protective eye wear
and other protective clothing if the
situation warrants it.
Be aware of
potential crushing
hazards such as moving parts, free
swinging or unsecured components
when lifting or placing loads. Always
wear approved steel
-toed shoes.
Workplace Safety
Any person working on or around a machine
must be aware of all known safety hazards.
Personal safety and the continued safe
operation of the machine should be your top
priority.
Be sure to keep sparks, flames and
lighted tobacco away from flammable
and combustible materials like battery
gases and engine fuels. Always have
an approved fire extinguisher within
easy reach.
Be sure that all tools and working
areas are properly maintained and
ready for use. Keep work surfaces
clean and free of debris that could get
into machine components and cause
damage.
Be sure any forklift, overhead crane or
other lifting or supporting device is
fully capable of supporting and
stabilizing the weight to be lifted. Use
only chains or straps that are in good
condition and of ample capacity.
Be sure that fasteners intended for
one time
use (i.e., cotter pins and self
-
locking nuts) are not reused. These
components may fail if they are used
a second time.
Be sure to properly dispose of old oil
or other fluids. Use an approved
container. Please be environmentally
safe.
Be sure
that your workshop or work
area is properly ventilated and well lit.

March 2022
Table of Contents
Part No. 1312899GT GR™-20J • GR™-26J vii
Introduction Introduction ......................................................................................................ii
Important Information ......................................................................................... ii
Revision History ................................................................................................ iii
Serial Number Legend....................................................................................... iv
Section 1 Safety Rules......................................................................................................v
General Safety Rules .........................................................................................v
Section 2 Specifications...................................................................................................1
Machine Specifications .......................................................................................1
Performance Specifications ................................................................................2
Hydraulic Component and Manifold Specifications..............................................3
Manifold Component Specifications ....................................................................3
Hydraulic Oil Specifications ................................................................................4
Hydraulic Hose and Fitting Torque Specifications ...............................................5
Torque Procedure ..............................................................................................6
SAE and Metric Fasteners Torque Charts...........................................................8

March 2022
Table of Contents
viii GR™-20J • GR™-26J Part No. 1312899GT
Section 3 Scheduled Maintenance Procedures .............................................................. 9
Introduction........................................................................................................ 9
Pre-Delivery Preparation Report....................................................................... 12
Maintenance Inspection Report ........................................................................ 14
Checklist A Procedures ................................................................................. 15
A-1 Perform 30 Day Service............................................................................. 15
A-2 Replace the Hydraulic Suction Strainer ...................................................... 15
Checklist B Procedures ................................................................................. 17
B-1 Inspect the Batteries .................................................................................. 17
B-2 Inspect the Electrical Wiring....................................................................... 19
B-3 Inspect the Tires and Wheels..................................................................... 20
B-4 Test the Drive Brakes ................................................................................ 21
B-5 Test the Drive Speed – Stowed Position .................................................... 22
B-6 Test the Drive Speed – Raised Position ..................................................... 23
B-7 Test the Flashing Beacon (if equipped) ...................................................... 24
B-8 Test the Motion Alarm................................................................................ 24
B-9 Visual Inspection of the Hydraulic Oil ......................................................... 25
B-10 Inspect the Breather Cap ......................................................................... 26
B-11 Inspect the Rear Axle Free-wheel ............................................................ 27
B-12 Inspect the Lateral Offset of the Mast....................................................... 28
B-13 Inspect the Mast Wear Pads .................................................................... 29
Checklist C Procedures ................................................................................. 30
C-1 Calibrate the Platform Overload System .................................................... 30
C-2 Repalce the Hydraulic Tank Breather Cap –
Models with Optional Hydraulic Oil............................................................ 31
Checklist E Procedures ................................................................................. 32
E-1 Test or Replace the Hydraulic Oil............................................................... 32

March 2022
Table of Contents
Part No. 1312899GT GR™-20J • GR™-26J ix
Section 4 Repair Procedures..........................................................................................33
Introduction ......................................................................................................33
Platform Controls ...........................................................................................35
1-1 Circuit Boards.............................................................................................35
1-2 Controller Adjustments ...............................................................................35
How to Activate or Deactivate the Motion Alarm...........................................36
How to Activate or Deactivate the Flashing Beacon (if equipped) .................37
How to Calibrate the Joystick.......................................................................38
How to Calibrate the Steer Angle Sensor.....................................................39
Platform Components ....................................................................................41
2-1 Platform......................................................................................................41
2-2 Platform Overload System ..........................................................................42
Jib Components .............................................................................................44
3-1 Jib Cylinder ................................................................................................44
Mast Components ..........................................................................................46
4-1 Mast Assembly...........................................................................................46
How to Remove the Mast Assembly ............................................................46
How to Disassemble the Mast, GR-26J........................................................50
How to Assemble the Mast, GR-26J ............................................................53
How to Disassemble the Mast, GR-20J........................................................56
How to Assemble the Mast, GR-20J ............................................................57
4-2 Lift Cylinder ................................................................................................59
Ground Controls.............................................................................................61
5-1 Level Sensor ..............................................................................................61
Hydraulic Pump ..............................................................................................62
6-1 Hydraulic Pump ..........................................................................................62

March 2022
Table of Contents
x GR™-20J • GR™-26J Part No. 1312899GT
Function Manifold .......................................................................................... 64
7-1 Function Manifold Components.................................................................. 64
7-2 Valve Adjustments – Function Manifold ...................................................... 66
Hydraulic Tank ............................................................................................... 68
8-1 Hydraulic Tank........................................................................................... 68
Turntable Components.................................................................................. 69
9-1 Turntable Rotation Hydraulic Motor ............................................................ 69
9-2 Battery ....................................................................................................... 70
Steer Axle Components................................................................................. 71
10-1 Yoke ........................................................................................................ 71
10-2 Steer Cylinder .......................................................................................... 71
10-3 Steering Rod............................................................................................ 72
10-4 Steer Angle Sensor.................................................................................. 73
Non-Steer Axle Components......................................................................... 75
11-1 Drive Motors ............................................................................................ 75
11-2 Drive Brake.............................................................................................. 77
Battery Charger.............................................................................................. 78
12-1 Battery Charger........................................................................................ 78
Battery Charger Staus Indicator ....................................................................... 79
Battery Charger not Operating.......................................................................... 79
How to Reset the Battery Charger .................................................................... 80

March 2022
Table of Contents
Part No. 1312899GT GR™-20J • GR™-26J xi
Section 5 Fault Codes.....................................................................................................81
Introduction ......................................................................................................81
Fault Code Chart ..............................................................................................83
Section 6 Schematics .....................................................................................................95
Introduction ......................................................................................................95
ECM Pin Legend ..............................................................................................96
Limit Switch and Sensor Legend.......................................................................98
Electrical Symbols Legend................................................................................99
Hydraulic Symbols Legend .............................................................................100
Electrical Schematics...................................................................................101
Electrical Schematic, GRJ (from GRJL-2298) .................................................102
GCON LED Panel, GRJ (from GRJL-2298).....................................................106
Temperature Sensor Harness, GRJ (from GRJL-2298)...................................107
Options, GRJ (from GRJL-2298).....................................................................110
Hydraulic Schematics ..................................................................................111
Hydraulic Schematic, 2.2 kw (from GRJL-2298)..............................................112
Hydraulic Schematic, 3 kw (from GRJL-2298).................................................113

Service Manual March 2022
xii GR™-20J • GR™-26J Part No. 1312899GT
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March 2022 Service Manual
Specifications
Part No. 1312899GT GR™-20J • GR™-26J 1
Sec ti on 2 Speci fic ati o ns
Machin e Spec ific atio ns
Machine Specifications
Batteries, Standard
Voltage
2V DC
Group
AS/CE/UK -
C5
ANSI/CSA -
C20
Quantity
12
Battery capacity, maximum
AS/CE/UK -
250 AH
ANSI/CSA - 270 AH
Weight
500 l
bs
227 k
g
Fluid capacities
Hydraulic tank
5.8 g
allons
22 liters
For operational specifications, refer to the
Operator's Manual.
Tires and wheels
Tire size (solid rubber)
16 x 5 x 11 i
n
40,6 x 12,7 x 28 cm
Castle nut torque, dry
89 ft-
lbs
120 Nm
Castle nut torque, lubricated
66 ft-
lbs
90 Nm
Lug nut
torque, dry 132 ft-
lbs
180 Nm
Lug nut torque, lubricated
96 ft-
lbs
130 Nm
Turntable bearing
Rotate bearing mounting bolts,
lubricated
70 ft-
lbs
95 Nm
Rotate bearing mounting bolts,
dry
92 ft-
lbs
125 Nm

Service Manual March 2022
Specifications
2 GR™-20J • GR™-26J Part No. 1312899GT
Perfor man ce S peci fi catio ns
Performance Specifications
Drive speed, maximum
Platform stowed
2.8 m
ph
40 ft / 9.8 s
ec
4,5 k
m/h
12,2 m / 9,8 sec
Platform raised
0.4 m
ph
40 ft / 54.8 s
ec
0.65 k
m/h
12.2 m / 54.8 s
ec
Braking distance, maximum
High range on paved surface
60 i
n
152 c
m
Gradeability
See Operator's Manual
Function speed, maximum from platform controls
(with 1 person in platform)
GR-20J
Mast up
Mast down
24 - 26 s
econds
19 - 21 s
econds
GR
-26J
Mast up
Mast down
54 - 56 s
econds
40 - 42 s
econds
GR-20J, GR-26J
Jib boom up
Jib boom down
12 - 17 s
econds
21 - 26 s
econds
Turntable rotate, 350°
32 - 37 s
econds
For operational specifications, refer to the
Operator's Manual.

March 2022 Service Manual
Specifications
Part No. 1312899GT GR™-20J • GR™-26J 3
Hydrauli c Com pon ent and Manif ol d Sp ec ific ati ons
Hydraulic Component
Specifications
Function Pump
Type
Gear
Displacement per revolution
0.256 c
u in
4.2 c
c
Function manifold
System relief valve pressure, maximum
2030 psi
140 b
ar
Lift relief valve pressure
930 p
si
64 b
ar
Filter cap torque
37 ft-lbs
50 Nm
Torque
specifications
Brake mounting fasteners, dry
75 ft-
lbs
102 Nm
Brake mounting fasteners, lubricated
56 ft-
lbs
76 Nm
Grease specification
RETINAX HDX
2 grease, NLGI (lithium
based) or equivalent
Manif old Co mpo nent S peci fica ti ons
Manifold Component
Specifications
Plug torque
SAE No. 2
36 in-
lbs / 4 Nm
SAE No. 4
10 ft-lbs / 13 Nm
SAE No. 6
14 ft-
lbs / 19 Nm
SAE No. 8
38 ft-
lbs / 51 Nm
SAE No.10
41 ft-
lbs / 55 Nm
SAE No. 12
56 ft-
lbs / 76 Nm

Service Manual March 2022
Specifications
4 GR™-20J • GR™-26J Part No. 1312899GT
Hydraulic Oil Spec if ic ations
Hydraulic Oil Specifications
Hydraulic Fluid Specifications
Genie specifications require hydraulic oils which are
designed to give maximum protection to hydraulic
systems, have the ability to perform over a wide
temperature range, and
the viscosity index should
exceed 140. They should provide excellent antiwear,
oxidation prevention, corrosion inhibition, seal
conditioning, and foam and aeration suppression
properties.
Cleanliness level,
minimum
ISO 15/13
Water content,
maximum
200 p
pm
Recommended Hydraulic Fluid
Hydraulic oil type
Shell PW 46
Viscosity grade
Multi-viscosity
Viscosity index
152
Optional Hydraulic Fluids
Biodegradable
Texaco Hydra
46
Shell Naturelle HF-
E 46
Note: Genie specifications require additional
equipment and special installation instructions for
the approved optional fluids. Consult Genie
Product Support before use.
Optional fluids may not have
the same hydraulic lifespan and
may result in component
damage.
Note: Extended machine operation can cause the
hydraulic fluid temperature to increase beyond its
maximum allowable range. If the hydraulic fluid
temperature consistently exceeds 200°F / 90°C an
optional oil cooler may be required.
Do not top off with incompatible
hydraulic fluids. Hydraulic fluids
may be incompatible due to the
differences in base additive
chemistry. When incompatible
fluids are mixed, insoluble
materials may form and deposit
in the hydraulic system,
plugging hydraulic lines, filters,
control valves and may result in
component damage.
Note: Do not operate the machine when the
ambient air temperature is consistently above
120°F / 49°C.

March 2022 Service Manual
Specifications
Part No. 1312899GT GR™-20J • GR™-26J 5
Hydrauli c Hose and Fitti ng Torque Speci ficati ons
Hydraulic Hose and Fitting
Torque Specifications
Your machine is equipped with Parker Seal-Lok™
ORFS or 37° JIC fittings and hose ends. Genie
specifications require that fittings and hose ends
be torqued to specification when they are removed
and installed or when new hoses or fittings are
installed.
Seal-Lok™ Fittings
(hose end - ORFS)
SAE Dash Size
Torque
-4 18 ft-lbs / 25 Nm
-6 30 ft-lbs / 41 Nm
-8
40 ft-lbs / 55 Nm
-10 60 ft-lbs / 81 Nm
-12 85 ft-lbs / 115 Nm
-16 110 ft-lbs / 150 Nm
-20 150 ft-lbs / 205 Nm
-24 230 ft-lbs / 315 Nm
JIC 37° Fittings
(swivel nut or hose connection)
SAE Dash Size
Thread Size
Flats
-4 7/16-20 2
-6 9/16-18 1 1/2
-8 3/4-16 1 1/2
-10 7/8-14 1 1/2
-12 1 1/16-12 1 1/4
-16
1 5/16-12
1
-20 1 5/8-12 1
-24 1 7/8-12 1
SAE O-ring Boss Port
(tube fitting - installed into Aluminum)
(all types)
SAE Dash Size
Torque
-4 14 ft-lbs / 19 Nm
-6 23 ft-lbs / 31,2 Nm
-8
36 ft-lbs / 49 Nm
-10 62 ft-lbs / 84 Nm
-12 84 ft-lbs / 114 Nm
-16 125 ft-lbs / 169,5 Nm
-20 151 ft-lbs / 204,7 Nm
-24 184 ft-lbs / 249,5 Nm
Adjustable Fitting Non-adjustable fitting
1 jam nut
SAE O-ring Boss Port
(tube fitting - installed into Steel)
SAE Dash Size
Torque
-4 ORFS / 37° (Adj)
ORFS (Non-adj)
37° (Non-adj)
15 ft-lbs / 20,3 Nm
26 ft-lbs / 35,3 Nm
22 ft-lbs / 30 Nm
-6 ORFS (Adj / Non-adj)
37° (Adj / Non-adj)
35 ft-lbs / 47,5 Nm
29 ft-lbs / 39,3 Nm
-8 ORFS (Adj / Non-adj)
37° (Adj / Non-adj)
60 ft-lbs / 81,3 Nm
52 ft-lbs / 70,5 Nm
-10 ORFS (Adj / Non-adj)
37° (Adj / Non-adj)
100 ft-lbs / 135,6 Nm
85 ft-lbs / 115,3 Nm
-12
(All types)
135 ft-lbs / 183 Nm
-16 (All types) 200 ft-lbs / 271,2 Nm
-20 (All types) 250 ft-lbs / 339 Nm
-24 (All types)
305 ft-lbs / 413,5 Nm

Service Manual March 2022
Specifications
6 GR™-20J • GR™-26J Part No. 1312899GT
Torque P roce dur e
Torque Procedure
Seal-Lok™ fittings
1 Replace the O-ring. The O-ring must be
replaced anytime the seal has been broken.
The O-ring cannot be re-used if the fitting or
hose end has been tightened beyond finger
tight.
Note: The O-ring in Parker Seal Lok™ fittings and
hose end are custom-size O-rings. They are not
standard size O-rings. They are available in the O-
ring field service kit (Genie part number 49612).
2 Lubricate the O-ring before installation.
3 Be sure the O-ring face seal is seated and
retained properly.
4 Position the tube and nut squarely on the face
seal end of the fitting, and tighten the nut
finger tight.
5 Tighten the nut or fitting to the appropriate
torque. Refer to the appropriate torque chart
in this section.
6 Operate all machine functions and inspect the
hose, fittings and related components to
confirm there are no leaks.
JIC 37° fittings
1 Align the tube flare (hex nut) against the nose
of the fitting body (body hex fitting) and
tighten the hex nut to the body hex fitting to
hand tight, approximately 30 in-lbs / 3.4 Nm.
2 Using a permanent ink marker, make a
reference mark on one the flats of the hex nut
and continue the mark onto the body of the
hex fitting. Refer to Illustration 1.
Illustration 1
1 hex nut
2 reference mark
3 body hex fitting

March 2022 Service Manual
Specifications
Part No. 1312899GT GR™-20J • GR™-26J 7
3 Working clockwise on the body hex fitting,
make a second mark with a permanent ink
marker to indicate the proper tightening
position. Refer to Illustration 2.
Note: Use the JIC 37° Fitting table in this section
to determine the correct number of flats, for the
proper tightening position.
Note: The marks indicate the correct tightening
positions have been determined. Use the second
mark on the body hex fitting to properly tighten the
joint after it has been loosened.
Illustration 2
1 body hex fitting
2 reference mark
3 second mark
4 Tighten the hex nut until the mark on the hex
nut is aligned with the second mark on the
body hex fitting.
5 Operate all machine functions and inspect the
hose, fittings and related components to
confirm there are no leaks.

Service Manual March 2022
Specifications
8 GR™-20J • GR™-26J Part No. 1312899GT
SA E and Me tric Fastene rs Torq ue C h arts