INTRODUCTION
parts of the lifting mechanism are the cylinder, links,
GENERAL
tension rods and load wheel assemblies. The cylinder
This section has the description, repair and adjustment
fastens between the drive unit frame and the fork
procedures for the W/B/C60-80XT units. A
weldments.
troubleshooting table for the lift mechanism is at the end
The upper links fastens between the weldments. The
of this section. The lifting mechanism is operated by the
lower linkage (rockers) are attached between both
hydraulic system. The lifting mechanism raises the fork
weldments and the tension rods. Each tension rod
weldment.
fastens between one of the rockers and a wheel support.
When the cylinder extends, it lifts the fork weldment
DESCRIPTION (See Figure 1)
and makes the linkage move. As the rockers rotate, each
Most of the truck s lifting mechanism fastens between tension rod pushes a wheel support down. This action
the drive unit frame weldment and fork weldment. The raises the tips of the forks.
1. HYDRAULIC CYLINDER
2. UPPER LINK
3. ROCKER
B60XT SHOWN
4. ROCKER PIVOT PIN
OTHER MODLES
5. TENSION ROD SIMILAR
6. WHEEL SUPPORT
7. YOKE
8. WHEEL SUPPORT PIN
7
8
1
2
3
4
6
5
FIGURE 1. LIFTING MECHANISM
REPAIRS
weldment. The following list has the sections giving the
REMOVAL AND DISASSEMBLY
(See Figure 2 and Figure 6) correct removal and installation procedures for these
parts. Select the section that includes the parts that must
Electrical and hydraulic parts must be removed to
separate the main frame weldment from the fork
1
be removed. For the electrical system see the sections can cause serious injury. NEVER put hands, arms,
THE ELECTRICAL SYSTEM, 2200 SRM 279, head or legs between these parts unless the parts
CURTIS TRANSISTOR MOTOR CONTROL- have blocks to prevent movement.
LER, 2200 SRM 411 or DIAGRAMS CURTIS
TRANSISTOR, 8000 SRM 457. For the hydraulic
WARNING
system see the section THE WALKIE HYDRAULIC
SYSTEM, 1900 SRM 278.
Be careful when removing or installing snap rings.
These snap rings can come loose during removal or
Separate parts of the lifting system can be removed
installation with enough force to cause an injury. Al-
without disassembling the complete mechanism. It is
ways use the correct snap ring pliers and wear eye
not necessary to do EACH step of the procedure to
protection during removal and installation.
remove just one part. This procedure has steps to
remove and disassemble the complete lifting
4. To remove the lift cylinder, remove the snap rings
mechanism. Read the procedure and do only the
from the anchor pin that fasten the bottom of the
necessary steps.
cylinder to the main frame weldment. Use a drift to
remove the anchor pin. Have a person hold the cylinder
1. Put a solid wood or metal block under each side of
so that it can not fall. Use a drift to remove the roll pin
the drive unit frame weldment, near the rockers. The
retaining the upper anchor pin to the fork weldment.
blocks must be thick enough to just fit under the drive
Drive the upper anchor pin from the frame weldment.
unit frame weldment. The drive unit frame weldment
must not lower or tilt when the fork weldment is
5. Lift the cylinder and put it in a position so that the
removed. See the section PERIODIC MAINTE-
hydraulic lines are on top. There is oil inside the
NANCE, 8000 SRM 281.
cylinder. Install labels for the correct connection during
assembly and remove the hydraulic lines. Put caps on
2. Raise the forks to the maximum height. Put solid
the hydraulic lines and the ports to prevent the oil from
wood or metal blocks under both sides of the fork
draining out.
weldment at the fork tips and at the battery. The four
blocks must prevent the fork weldment from tipping to
either side. Push the  LOWER button. Remove the
6. If the hydraulic cylinder must be disassembled do
drive unit compartment hood.
the following steps:
a. Hold the cylinder over a container and
WARNING
remove the caps from the hydraulic ports. Drain
The capacitor in the transistor controller can hold an the oil from the rod port of the cylinder into a
electrical charge after the battery is disconnected. To container by pulling on the rod.
prevent electrical shock and injury, discharge the ca-
b. Use a spanner wrench to remove the piston
pacitor before inspecting or repairing any compo-
head.
nent in the drive unit compartment. Wear safety
glasses. Make certain the battery has been discon-
c. Remove the piston head and rod assembly
nected. Use a screwdriver or jumper wire to make a
from the shell.
short circuit across the B + and B  terminals of the
transistor controller.
NOTE: Replace all wipers and seals whenever a
cylinder is disassembled.
3. Remove the battery as shown in the section
PERIODIC MAINTENANCE, 8000 SRM 281.
d. Place the flat surface of the piston rod
assembly into a soft jawed vise. Remove the
locknut, piston head with the seal and retainer
WARNING
from the rod. Remove the seal from the piston
There are close clearances between the MDU, the
head.
fork weldment and the main frame weldment that
2
47
1. MDU FRAME WELDMENT
2. FORK WELDMENT
46
3. HYDRAULIC CYLINDER
45
4. ANCHOR PIN
5. ROLL PIN
6. SNAP RING
2
7. ANCHOR PIN
4
3
44
43
6
42
41
39
5 40
7
1
6
38
8
37
36
35
9
10
31
11
34
12
5
15 33
32
14
31
10
13
30
29
15
28
26
27
16
25
17
22
16
18
21
24
19
20
23
8. BUSHING
9. LUBE FITTING 22. BUSHING 35. PIVOT PIN
10. BUSHING 23. LOCKWASHER 36. WHEEL SUPPORT ASSEMBLY
11. LUBE FITTING 24. CAPSCREW 37. CAPSCREW
12. ROLL PIN 25. PIVOT PIN 38. PIVOT PIN
13. PIVOT PIN 26. PIVOT PIN 39. NUT
14. UPPER LEVER 27. LOCKWASHER 40. SET SCREW
15. LUBE FITTING 28. CAPSCREW 41. SPACER
16. LUBE FITTING 29. BUSHING 42. ROLLER
17. ROCKER 30. TENSION ROD 43. CAPSCREW
18. BUSHING 31. JAM NUTS 44. WEAR STRIP
19. CAPSCREW 32. YOKE 45. NUT
20. PIVOT PIN 33. BUSHING 46. ACCESS PLATE
21. NUT 34. LUBE FITTING 47. CAPSCREW
FIGURE 2. LIFT LINKAGE
3
e. Remove the wiper seal from the retainer.
1
9 7
7. To remove the upper linkage, remove the roll pins
retaining the pivot pins to the main drive unit weldment.
Remove the pivot pins. Remove the roll pins retaining
the lower pins to the fork weldment. Remove the pins
6
and upper link from the fork weldment. On the
C60-80XT units disconnect the high speed pedal
7
harness before separating the weldments. Separate the
drive unit frame weldment from the fork weldment.
2
3
4
8. Remove the capscrews and lockwashers retaining
8
the pivot pin to the fork weldment. Remove the pivot 5
4
3
2
pins from the drive unit frame weldment and the
rockers.
1. WHEEL SUPPORT 6. ROLL PIN
2. GUARD 7. LUBE FITTING
9. Remove the capscrews and lockwashers retaining
3. WAVE WASHER 8. AXLE
the pivot pins to the rocker arms and the tension rods.
4. BEARING 9. BUSHING
Remove the pivot pins and the rockers. The fork
5. LOAD WHEEL
weldment may now be separated from the drive unit
frame weldment.
FIGURE 3. WHEEL SUPPORT - SINGLE
10. Remove the capscrews and locknuts retaining the
LOAD WHEEL
torsion rods to the wheel supports. Remove the pivot
pins, spacers, rollers and torsion rods.
8
1
10 3
2
11. Remove the set screws retaining the wheel support
4
pivot pin. Use a drift to drive the pivot pin from the fork
weldment and wheel support.
7
12. If either wheel support must be disassembled do
9
the following steps:
8
5
4
4
3
3
2
6
Single and Dual Wheels (See Figure 3 and
3
Figure 4)
4
5
1. WHEEL SUPPORT 6. SPACER
CAUTION
2. GUARD 7. ROLL PIN
Do not drive the axle from the end with the grease fit-
3. WAVE WASHER 8. LUBE FITTING
ting installed.
4. BEARING 9. AXLE
5. LOAD WHEEL 10. BUSHING
a. Use a punch to remove the roll pin that
fastens the axle and the load wheel. Use a drift to
remove the axle from the wheel support.
FIGURE 4. WHEEL SUPPORT - DUAL
LOAD WHEEL
b. Remove the axle, guards, wave washers,
bearings and load wheels from the wheel support.
Tandem Wheels (See Figure 5)
c. Use a press to remove the bushings from the a. Remove the nuts retaining the front load
wheel support. wheels to the bracket. Remove the capscrew,
4
bearings, wave washers, washers and axle sleeve. Single and Dual Wheels (See Figure 3 and
Figure 4)
Repeat for the rear load wheel.
a. Use a press or a block of wood and a hammer
b. Remove the brackets, shims and bushings
to install the bearings into the wheel.
from the wheel support.
b. Align the wheel and bearing assembly and
the wave washers and guards with the opening in
c. Use a press to remove the bushings from the
the wheel support. On the dual wheel assembly
wheel support.
install the spacer between both inner wave
washers. Install the axle shaft. Install the roll pin
13. Remove the jam nuts retaining the torsion rods to
to fasten the axle in the wheel support.
the yokes.
c. Align the wheel support assembly in the fork
14. Remove capscrews and nuts retaining the wear
weldment. Align the roller and spacer inside the
strips.
wheel support assembly and install the pivot pin
to retain the roller, spacer and wheel support
assembly to the frame weldment. Align the pivot
WARNING
pin and install the set screw.
Cleaning solvents can be flammable and toxic, and
d. Install new grease fittings if necessary.
can cause skin irritation. Wear protection when han-
dling solvents and always follow the recommenda-
Tandem Wheels (See Figure 5)
tions of the manufacturer.
a. Use a press or a block of wood and a hammer
15. Clean and inspect all components for damage or
to install the bearings into the load wheels. Install
wear. Replace any item that is worn or damaged. Use a
the axle sleeves in the load wheels.
press or a block of wood and a hammer to remove the
bushings when necessary.
b. Position the shims and brackets on the wheel
support. Align the load wheels with the bearings
and sleeves between the wave washers, washers
ASSEMBLY AND INSTALLATION
and the brackets and install the axles. Install the
nuts on the axles.
This assembly and installation procedure is for a lifting
c. Align the wheel support assembly in the fork
mechanism that is completely disassembled. Do only
weldment. Align the roller and spacer inside the
the steps necessary to assemble and install the parts of
wheel support assembly and install the pivot pin
your unit that have been removed.
to retain the roller, spacer and wheel support
assembly to the fork weldment. Align the pivot
1. Use a bearing tool or a block of wood and a hammer
pin and install the set screw.
to install the bushings in all the linkage, including the
upper links, drive unit frame weldment, fork weldment,
d. Install new grease fittings if necessary.
rockers, tension rods, yokes and wheel supports. Align
4. Assemble the torsion rods to the yokes. The length
the bushings and linkage so that the edges are even.
of the torsion rods must be adjusted after the linkage has
After the bushings are installed, line drill a 3.05 mm
been completely assembled.
(0.12 in) diameter hole through each bushing, using
the grease fitting hole as a guide. Install the grease
5. Align the rockers with the fork weldment and
fitting.
install the pivot pins using the capscrews and nuts to
retain the rockers.
2. Install wear strips on the fork weldment, using the
capscrews and nuts to retain the strips. Tighten the 6. Position the torsion rods and yokes between the
capscrews to 35 NSm (26 lbf ft) torque. rockers and the wheel support assemblies. Install the
pivot pins to retain the yokes to the wheel support
3. Assemble the wheel support assemblies: assemblies. Install the capscrews and nuts to retain the
5
pivot pins. Align the torsion rods and the rockers and 7. Align the fork weldment and the rockers. Install the
install the pivot pins. Align the recess in the pivot pins pivot pins that retain the rockers to the fork weldment.
with the hole in the rockers and install the capscrew and Install the capscrews and nuts to retain the pivot pins.
lockwasher to retain the pivot pins.
8. Align the main frame weldment with the fork
weldment. Install the upper links to the frame weldment
using the lower pivot pins. Install the upper pivot pins to
1. SHIM
retain the main frame weldment and the upper links.
2. BUSHING
1
3. NUT
2
Install roll pins to retain both sets of pivot pins for the
3
4. BRACKET
4
upper links. Connect the high speed pedal harness.
5
5. WASHER
6
7
8 6. WAVE WASHER
9. Assemble the hydraulic cylinder if necessary.
NOTE: Put clean hydraulic oil on the seals and
9
7
wiper before assembly. Use the oil shown in Table 1
6
5
10 of the section PERIODIC MAINTENANCE, 8000
2
1
SRM 281.
12
12
11
a. Install a new wiper seal in the the piston head.
14
Install the piston head onto the piston rod. Install
a new seal in the piston groove. Install the piston,
piston seal and locknut on the piston rod. Align
the flat surfaces of the rod in a soft jawed vise and
12
13
tighten the locknut to 150 NSm (110 lbf ft) torque.
12
14
b. Put hydraulic oil on the inside of the shell as
7. BEARING 11. CAPSCREW
described in the NOTE above. Carefully install
8. LOAD WHEEL 12. LUBE FITTING
9. AXLE SLEEVE 13. WHEEL SUPPORT
the piston rod assembly into the shell. Do not
10. BRACKET 14. BUSHING
damage the seal or wiper during assembly.
CAUTION
FIGURE 5. WHEEL SUPPORT - TANDEM
WHEELS Do not allow any Loctite to get into the cylinder.
8
6
5
7
4
3
2
1
1. SHELL
2. LOCKNUT
3. SEAL
4. PISTON
5. PISTON HEAD
6. WIPER
7. PISTON ROD
8. BUSHING
FIGURE 6. HYDRAULIC CYLINDER
6
c. Put LoctiteRNo. 242 on the threads of the 12. Install the hydraulic lines to the hydraulic
piston head. Follow the directions of the cylinder. The hose assembly goes to the bottom port in
manufacturer. the cylinder.
d. Tighten the piston head to 27 NSm (20 lbf ft)
torque. 13. Lubricate all the grease fittings. Connect any
wires removed according to the labels. Install the
battery as shown in the section PERIODIC
WARNING
MAINTENANCE, 8000 SRM 281.
Be careful when removing or installing snap rings.
The snap rings can come loose during removal or
installation with enough force to cause an injury. Al-
14. Remove the blocks and lower the unit to the floor.
ways use the correct snap ring pliers and wear eye
Check the level of the hydraulic oil. Connect the battery
and face protection during removal and installation.
connector. Install the drive unit compartment hood.
10. Align the base of the cylinder in the main frame Operate the lift truck to check for correct operation. See
weldment. Install the anchor pin and snap rings. the OPERATING MANUAL.
CHECKS AND ADJUSTMENTS
TORSION ROD ADJUSTMENT
The torsion rods must be adjusted so that the machined
surface on top of the rear link is flush to the frame when
the lift truck is in the lowered position. If the rear link
machined surface is not flush to the fork frame or if the
load wheels are not carrying the load equally, an
adjustment must be made. Make certain to check both
forks and both load wheels.
1. Position a flat bar across one of the forks. Use a tape
rule or a ruler to measure the distance from the floor to
the top of the fork. Record the dimension.
FIGURE 7. MEASURING FORK -
LOWERED POSITION
6. Compare the measurements taken. If the
2. Move the flat bar to the other fork and make the
measurements taken are not within 4.6 mm (0.18 in) of
same measurement. Record the second measurement.
each other or if the load wheels are not carrying the load
equally an adjustment is required. The lowered fork
3. Turn the key to the ON position and raise the fork to
height at the load wheel end should be 81.03 to 85.60
its maximum height.
mm (3.19 to 3.37 in).
7. Remove the four capscrews retaining the access
4. Place the flat bar across the first fork that was
covers on each fork.
measured and take a measurement with the fork in the
raised position. Record the dimension.
CAUTION
Improper adjustment to the pull rods can cause
5. Move the flat bar to the other fork and take a excessive wear to one of the load wheels and poor
measurement of the second fork. pallet entry and exit . When making any adjustments
7
be certain that the measurements are the same on 9. After the adjustments have been made, tighten the
both forks. If an equal measurement can not be
jam nuts to 176 NSm (130 lbf ft) torque.
obtained, the problem may be a twisted frame. A
twisted frame must be replaced.
10. Install the covers and secure them using the four
access cover capscrews. tighten the capscrews to 19
NSm (7 lbf ft) torque.
REAR FORK ADJUSTMENT
NOTE: This adjustment is available only on lift
trucks that have double pallet forks.
1. Position a flat bar across one of the forks at the
battery end. Use a tape rule or a ruler to measure the
distance from the floor to the top of the fork. Record the
dimension.
FIGURE 8. MEASURING FORK - RAISED
POSITION
8. There are two nuts on either side of the rear link and
2. Move the flat bar to the other fork and make the
load wheel assembly. Loosen both outer jam nuts and
same measurement. Record the second measurement.
make the necessary adjustment to the inner jam nuts. To
lower the load wheels, turn the inner nuts clockwise.
This will shorten the working length of the pull rods. To 3. Turn the key to the ON position and raise the fork to
raise the load wheels, turn the inner nuts its maximum height.
counter-clockwise. The working length of the pull rod
will be increased.
4. Place the flat bar across the first fork that was
measured and take a measurement with the fork in the
raised position. Record the dimension.
5. Move the flat bar to the other fork and take a
measurement of the second fork.
6. Compare the measurements taken. If the
measurements taken are not within 4.6 mm (0.18 in) of
each other, an adjustment is required The lowered fork
height at the battery box end should be 82.80 to 88.90
mm (3.26 to 3.50 in).
7. Loosen the nuts retaining the capscrews on both
sides of the frame between the battery box and the drive
unit frame. Adjust the capscrew to obtain the proper
dimension when the forks are lowered. Tighten the nuts
FIGURE 9. ADJUSTING TORSION ROD to retain the capscrews.
8
TROUBLESHOOTING
PROBLEM POSSIBLE CAUSE
Forks will not raise Hydraulic oil level low. See the section PERIODIC
MAINTENANCE, 8000 SRM 281.
Hydraulic pump motor not operating. Check motor electrical power and
control circuits. See the section THE ELECTRICAL SYSTEM, 2200 SRM
411 and the section THE WALKIE HYDRAULIC SYSTEM, 1900 SRM
178. See also the section MAINTENANCE, 620 SRM 294.
Lowering solenoid or valve stays in the lowering position.
Forks will not hold a position Control valve or solenoid is damaged. See the section THE WALKIE
HYDRAULIC SYSTEM, 1900 SRM 178.
Hydraulic line has a leak.
Cylinder seal or wiper has a leak. See the steps in the REPAIR section
that describes cylinder disassembly and assembly.
9