PDF Service Manual Hyundai 15LC-7A 18LC-7A 20LC-7A Forklift - 1 MB
Access complete repair and maintenance information for your Hyundai 15LC-7A, 18LC-7A, and 20LC-7A series forklifts.
This service manual contains detailed procedures for everything from routine service to complete overhauls.
With clear diagrams and specifications, it empowers technicians to diagnose problems quickly and perform reliable repairs, keeping your fleet operational.
PDF Viewer
Viewer loads when you scroll here
SHARE THIS MANUAL
Download the PDF Manual
PDF viewer loading area
Text Preview from This Manual
The text below was extracted from the visible preview pages to help you confirm the manual contents before download.
--- Page 1 ---
CONTENTS
SECTION 1 GENERAL
Group 1 Safety Hints - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1-1
Group 2 Specifications - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1-5
Group 3 Periodic Replacement - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1-13
SECTION 2 REMOVAL AND INSTALLATION OF UNIT
Group 1 Structure - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2-1
Group 2 Removal and Installation of Unit - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2-2
SECTION 3 POWER TRAIN SYSTEM
Group 1 Structure and Operation - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 3-1
Group 2 Troubleshooting - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 3-15
Group 3 Test and adjustments - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 3-19
Group 4 Disassembly and Assembly - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 3-23
SECTION 4 BRAKE SYSTEM
Group 1 Structure and Function - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-1
Group 2 Operational Checks and Troubleshooting - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-6
Group 3 Tests and Adjustments - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-9
SECTION 5 STEERING SYSTEM
Group 1 Structure and Function - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-1
Group 2 Operational Checks and Troubleshooting - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-10
Group 3 Disassembly and Assembly - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-12
SECTION 6 HYDRAULIC SYSTEM
Group 1 Structure and Function - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 6-1
Group 2 Operational Checks and Troubleshooting - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 6-22
Group 3 Disassembly and Assembly - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 6-26
SECTION 7 ELECTRICAL SYSTEM
Group 1 Component Location - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 7-1
Group 2 Electrical Circuit - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 7-2
Group 3 Component Specification - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 7-9
Group 4 Connector Destination - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 7-10
Group 5 Troubleshooting - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 7-12
--- Page 3 ---
SECTION 1 GENERAL
Group 1 Safety Hints - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1-1
Group 2 Specifications - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1-5
Group 3 Periodic Replacement - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1-13
--- Page 4 ---
5. TORQUE CHART
Use following table for unspecified torque.
1) BOLT AND NUT
(1) Coarse thread
8T 10T
Bolt size
kgfÂm lbfÂft kgfÂm lbfÂft
M 6Ý1.0 0.85 ~ 1.25 6.15 ~ 9.04 1.14 ~ 1.74 8.2 ~ 12.6
M 8Ý1.25 2.0 ~ 3.0 14.5 ~ 21.7 2.7 ~ 4.1 19.5 ~ 29.7
M10Ý1.5 4.0 ~ 6.0 28.9 ~ 43.4 5.5 ~ 8.3 39.8 ~ 60.0
M12Ý1.75 7.4 ~ 11.2 53.5 ~ 81.0 9.8 ~ 15.8 70.9 ~ 114
M14Ý2.0 12.2 ~ 16.6 88.2 ~ 120 16.7 ~ 22.5 121 ~ 163
M16Ý2.0 18.6 ~ 25.2 135 ~ 182 25.2 ~ 34.2 182 ~ 247
M18Ý2.0 25.8 ~ 35.0 187 ~ 253 35.1 ~ 47.5 254 ~ 344
M20Ý2.5 36.2 ~ 49.0 262 ~ 354 49.2 ~ 66.6 356 ~ 482
M22Ý2.5 48.3 ~ 63.3 349 ~ 458 65.8 ~ 98.0 476 ~ 709
M24Ý3.0 62.5 ~ 84.5 452 ~ 611 85.0 ~ 115 615 ~ 832
M30Ý3.0 124 ~ 168 898 ~ 1214 169 ~ 229 1223 ~ 1656
M36Ý4.0 174 ~ 236 1261 ~ 1704 250 ~ 310 1808 ~ 2242
(2) Fine thread
8T 10T
Bolt size
kgfÂm lbfÂft kgfÂm lbfÂft
M 8Ý1.0 2.2 ~ 3.4 15.9 ~ 24.6 3.0 ~ 4.4 21.7 ~ 31.8
M10Ý1.2 4.5 ~ 6.7 32.5 ~ 48.5 5.9 ~ 8.9 42.7 ~ 64.4
M12Ý1.25 7.8 ~ 11.6 56.4 ~ 83.9 10.6 ~ 16.0 76.7 ~ 116
M14Ý1.5 13.3 ~ 18.1 96.2 ~ 131 17.9 ~ 24.1 130 ~ 174
M16Ý1.5 19.9 ~ 26.9 144 ~ 195 26.6 ~ 36.0 192 ~ 260
M18Ý1.5 28.6 ~ 43.6 207 ~ 315 38.4 ~ 52.0 278 ~ 376
M20Ý1.5 40.0 ~ 54.0 289 ~ 391 53.4 ~ 72.2 386 ~ 522
M22Ý1.5 52.7 ~ 71.3 381 ~ 516 70.7 ~ 95.7 511 ~ 692
M24Ý2.0 67.9 ~ 91.9 491 ~ 665 90.9 ~ 123 658 ~ 890
M30Ý2.0 137 ~ 185 990 ~ 1339 182 ~ 248 1314 ~ 1796
M36Ý3.0 192 ~ 260 1390 ~ 1880 262 ~ 354 1894 ~ 2562
1-10
--- Page 5 ---
2) INSTALLATION
After assembling mast components totally without piping connections, install mast assembly to the
equipment.
ö Installation procedure for each of mast component is the reverse of the removal procedure.
(1) Mast support cap
Η Check the mast support cap and spring pin for wear.
Θ Jack up the machine so that the front is raised and then using an overhead hoist assemble outer
mast to drive axle unit.
Ι Tighten mounting bolts to mast support cap.
ÂTightening torque : 19.9~26.9kgfÂm(144~195lbfÂft)
(2) Tilt cylinder pin
Hold the mast with a crane, operate the tilt control lever and align the holes, then knock the pin.
(3) Lift cylinder installation and adjustment
Η Assemble the lift cylinder inside the outer
mast, then tighten the stopper bolt. If the
cylinder assembly has been replaced,
adjust as follows so that the left and right
cylinders are synchronized at the
maximum lifting height.
Θ Assemble the cylinder rod to the inner
mast, and check the left-to-right play of
the mast at the maximum lifting height.
ö If play is to LEFT, install adjustment shim
to LEFT cylinder.
ö If play is to RIGHT, install adjustment
L15C3RE12
shim to RIGHT cylinder.
ÂShim thickness : 1.0mm(0.04in)
2-6
--- Page 6 ---
(2) Rear wheel
Remove mounting bolt and hub nut with
socket wrench and then carefully take out
the tire assembly.
20D7RE28
(3) Hose
Drain hydraulic oil in the hoses and
cylinder before removing them.
Loosen connector and then disconnect
the hoses.
15L7RE29
(4) Mounting bolt
Put a block under the steering axle,
support on a truck, and raise the frame
with a crane. Remove the mounting bolts
installing to the frame, and pull out to the
rear.
There are shims between the support and
steering axle to prevent play.
15L7RE30
2-16
--- Page 7 ---
4. CONTROL VALVE
1) STRUCTURE
17 18 19 16 32 20
15 A
C B
33
1
21
28
29
C
30
B 31
11
22
25
23
27
26 24
R
8,9 F 2
7
3
10 A
4
(From COOLER) (To COOLER)
6 12
13
35 34 SECTION A-A 14 5
38 36
37
F R
D153PT28
1 Body 14 Spring 27 Snap ring
2 Plug 15 Plug 28 Valve
3 Piston 16 Piston 29 Spring
4 Valve 17 Stopper 30 Stopper
5 Stopper 18 Spring 31 Nut
6 Valve 19 Spring 32 Screw
7 Plate 20 O-ring 33 Screw
8 Washer 21 Solenoid valve 34 Nipple
9 Bolt 22 Oil seal 35 Spring washer
10 O-ring 23 Plug 36 Plug
11 O-ring 24 Spring 37 Washer
12 Spring 25 Spool 38 Plug
13 Spring 26 Plate
3-9
--- Page 8 ---
GROUP 3 TESTS AND ADJUSTMENTS
1. INCHING PEDAL
1) Depress inching pedal fully, and move gear
shift lever to FORWARD or REVERSE. Inching stroke
15~35mm
Check that machine does not move even
when engine speed is increased slightly.
2) Adjust stopper bolt so that pedal height is Pedal height
174-184mm
174~184mm (6.9~7.2 in).
3) Adjust bolt so that brake pedal interconnects
Floor plate
with inching pedal at a stroke of 15~35mm
(0.6~1.4in).
15LC7BS12
2. HYDRAULIC PRESSURE
1) Block wheels of truck, and pull parking lever. Install oil pressure gauge at inlet of control valve.
2) Move direction control lever to FORWARD or REVERSE, depress accelerator pedal and run engine
at 1500rpm. Measure clutch pressure and torque converter pressure and check that they are within
specified range.
3. ENGINE STALL SPEED
Move direction control lever to FORWARD or REVERSES, and run engine at maximum speed.
Check that maximum engine speed is within specified range.
ö This check raises the temperature of the oil in the torque converter, so do not run this test for
a long period.
Model Stall speed
HYUNDAI beta 1680Ü100rpm
4. DIFFERENTIAL
1) Fitting differential assembly
(1) Install the differential assembly and fit
adjust screw gear(1).
Loctite
(2) Apply loctite in the hole of cap(2), and #271
temporarily tighten with bolt(3). 3 1
2) Adjustment of backlash
ö Tighten the adjust screw gear(1). 2
L15C3DF01
3-19
--- Page 9 ---
Unit : mm(in), kg(lb)
Criteria
No. Check item Remedy
Standard size Repair limit
Clearance between piston 0.015-0.025 0.065 Replace
A1 and housing hole (0.0006-0.001) (0.0025) piston
Free 89.9 87.3
length (3.54) (3.43)
Torque converter Installed 63 63
Torque A2 inlet relief valve length (2.48) (2.48)
spring
converter Installed 7.70 6.94
A load (16.98) (15.3)
input output
Free 122 120.4
valve length (4.80) (4.74)
Torque converter
output pressure Installed 103.5 103.5
A3 adjusting valve length (4.07) (4.07)
spring Installed 3.45 3.11
load (7.61) (2.36)
60
B Oil seal O.D - (2.36)
Torque converter Oil seal mating 59.952-60.000 59.852 Replace
C impeller valve C1 face outer dia (2.360-2.362) (2.356)
Clearance of abutment 0.1-0.3 1.0
E1 when housing is inserted (0.004-0.012) (0.04)
E Seal spring
2.47-2.49 2.7
E2 Ring with (0.097-0098) (0.089)
2.56-2.60 2.7
F Turbine shaft(Seal ring groove width) (0.100-0.102) (0.106)
48.0-48.025 48.12
G Housing(Seal ring portion inner dia) (1.889-1.890) (1.894)
47.951-47.970 Clearance
H Impeller hub O.D (1.887-1.888) between hub
47.975-48.000 and bushing
I Pump bushing (1.889-1.890) 0.1(0.0039)
Corrected
15 14.85 by hard
J Pilot(Tip outer dia) Isuzu engine chrome
(0.59) (0.38)
plating
3-29
--- Page 10 ---
3. DIFFERENTIAL
1) STRUCTURE
TRANSMISSION
Loctite #271
12
11
6
5
7
18~20 kgf . m
(130~144 lbf . ft) 3 4
. 2 6
5~7.5 kgf m 5
13 (36~54 lbf . ft) 8 7
Loctite #271(Hole side) 8
5 5
6
6
(Run out : Max, 0.1 with
dial guage reading) 9
1
Adjust with item 12
9~16 kgf . m 10
(65~116 lbf . ft) 14
Loctite #271(Hole side)
13
11
Starting torque : 35~43.5 kgf . m
(253~325 lbf . ft) 12
L15C3DF04
ö Ring gear and pinion must be replaced as one unit.
Do not replace one without the other.
1 Case 6 Washer 11 Taper bearing
2 Case 7 Differential pinion 12 Screw gear
3 Hexagon bolt 8 Bushing 13 Bolt
4 Spider 9 Bevel gear 14 Plate
5 Differential pinion 10 Bolt
3-39
--- Page 11 ---
5. WHEEL BRAKE
1) STRUCTURE
The wheel brake assembly mounts to the flange on the drive axle housing casting and is basically
contained within the hub assembly.
The inside of the hub is machined and acts as the brake drum.
20
21
4
3
19
11 5
9
10
2 13
14
1
15
12
6
7 16
8 17
7
18
15LC7BS03
1 Back plate-LH/RH 8 Shoe hole down spring 15 Adjuster guide
2 Wheel cylinder 9 Shoe hole down pin 16 Shoe return spring
3 Spring washer 10 Strut 17 Adjuster lever-LH/RH
4 Cylinder bolt 11 Strut spring 18 Adjuster spring
5 Shoe & lining assembly sec 12 Adjuster assembly-LH/RH 19 Rubber
6 Shoe & lining assembly pri-LH/RH 13 Shoe guide 20 Parking cable assembly-LH/RH
7 Shoe hole down cup 14 Adjuster cable 21 E-ring
4-4
--- Page 13 ---
SECTION 5 STEERING SYSTEM
GROUP 1 STRUCTURE AND FUNCTION
1. OUTLINE
Steering wheel
Priority valve
Steering cylinder
LS
Steering unit
CF
T
L
P LS
R
Hydraulic tank
15LC7SS01
The steering system for this machine is composed of steering wheel assembly, steering unit,
steering cylinder, steering axle and pipings. The steering force given to the steering wheel enters
the steering unit through the steering column. The required oil flow is sensed by the function of the
control section of the unit, and pressurized oil delivered from the hydraulic pump is fed to the
steering cylinder. The force produced by the steering cylinder moves the knuckle of steering tires
through the intermediate link.
The axle body is unit structure having steering knuckles installed to its both ends by means of
kingpins. Hub and wheel are mounted through bearing to spindle of knuckle.
5-1
--- Page 14 ---
Problem Cause Remedy
Steering wheel turns unstea- ÂLockout loosening. ÂRetighten.
dily. ÂMetal spring deteriorated. ÂReplace.
Steering system makes abn- ÂGear backlash out of adjustment. ÂAdjust.
ormal sound or vibration. ÂLockout loosening. ÂRetighten.
ÂAir in oil circuit. ÂBleed air.
Abnormal sound heard when Valve
steering wheel is turned fully ÂFaulty. (Valve fails to open.) ÂAdjust valve set pressure and check
for specified oil pressure.
Piping
ÂPipe(from pump to power steering ÂRepair or replace.
cylinder) dented or clogged.
Piping makes abnormal Oil pump
sounds. ÂLack of oil. ÂAdd oil.
ÂOil inlet pipe sucks air. ÂRepair.
ÂInsufficient air bleeding. ÂBleed air completely.
Valve or valve unit makes Oil pump
abnormal sounds. ÂOil inlet pipe sucks air. ÂRepair or replace.
Valve
ÂFaulty. (Unbalance oil pressure) ÂAdjust valve set pressure and check
specified oil pressure.
Piping
ÂPipe(from pump to power steering) ÂRepair or replace.
dented or clogged.
ÂInsufficient air bleeding. ÂBleed air completely.
Insufficient or variable oil flow. ÂFlow control valve orifice clogged. ÂClean
Insufficient or variable dischar- Piping
ge pressure. ÂPipe(from tank to pipe) dented or ÂRepair or replace.
clogged.
Steering cylinder head ÂPacking foreign material. ÂReplace
leakage (Piston rod) ÂPiston rod damage. ÂGrind surface with oil stone.
ÂRod seal damage and distortion. ÂReplace
ÂChrome gilding damage. ÂGrind
Steering cylinder head thread ÂO-ring damage. ÂReplace
(A little bit leak is no problem)
Welding leakage ÂCylinder tube damage. ÂTube replace.
Rod ÂTube inside damage. ÂGrind surface with oil store.
ÂPiston seal damage and distortion ÂReplace
Piston rod bushing inner ÂBushing wear. ÂReplace
diameter excessive gap
5-11
--- Page 15 ---
(5) Press the springs together and push the
neutral position springs into place in the
sleeve.
5-77(2)
(6) Line up the springs and center them.
5-77(3)
(7) Guide the ring down over the sleeve.
ö The ring should be able to rotate free of
the springs.
5-77(4)
(8) Fit the cross pin into the spool / sleeve.
5-78(1)
5-21
--- Page 16 ---
2) DISASSEMBLY
ö Before disassembling steering cylinder, release oil in the cylinder first.
(1) Put wooden blocks against the cylinder tube, then hold in a vice.
(2) Remove the gland by hook a wrench in the notch of cylinder head and turn counter-clockwise.
(3) Remove the cylinder rod and piston from the tube.
(4) Check wear condition of the sealing parts. If there are some damage, replace with new parts.
3) CHECK AND INSPECTION mm(in)
Criteria
Check item Remedy
Standard size Repair limit
Clearance between 0.064~0.137 0.180 Replace
piston & cylinder tube (0.0025~0.0054) (0.0070) piston seal
Clearance between 0.024~0.112 0.120 Replace
cylinder rod & bushing (0.0009~0.0044) (0.0049) bushing
Seals, O-ring Damage Replace
Cylinder rod Dents Replace
Cylinder tube Biting Replace
4) ASSEMBLY
(1) Install a new piston seal the groove on the piston.
ö Be careful not to scratch the seal too much
during installation or it will not seat properly.
D353SE27
(2) Install the rod seal to the position in the gland
applying a slight coat with grease prior to install.
D353SE28
5-31
--- Page 17 ---
2) WHEN THE LIFT CONTROL LEVER IS IN THE LOWER POSITION
7 6
10 9
3
Steering system
2
1
11
8
Return line
12
15LC7AHS04
When the lift control lever is pushed forward, the spool on the first block moves to lower position.
The work port(1A) and the small and the large chamber of lift cylinder are connected to the return
passage, so the fork will be lowered due to its own weight.
6-4
--- Page 18 ---
5) STRUCTURE (4 SPOOL - TRAVEL WITH MAST OPSS)
2A 3A 4A
2B 3B 4B
16 17 11 12 13 15 15 14
15L7HS57
Port name Size
Inlet port 7/8-14UNF
Outlet port 7/8-14UNF
Work port 3/4-16UNF
11 Inlet block assy 15 Auxiliary block assy
12 Lift block assy 16 Long bolt
13 Tilt block assy 17 Nut
14 Outlet block assy
6-14
--- Page 19 ---
2) HYDRAULIC GEAR PUMP
Problem Cause Remedy
Pump does not develop full ÂSystem relief valve set too low or ÂCheck system relief valve for proper
pressure. leaking. setting.
ÂOil viscosity too low. ÂChange to proper viscosity oil.