Yale 524150797, Maintenance Manual

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Hydraulic Pump
REMOVE
1. Remove the hydraulic unit from the lift truck. Re-
fer to the Figure 4 or Figure 5 in this section.
2. Clean the reservoir and pump area to prevent
contaminants from entering the hydraulic system.
3. Remove the capscrews retaining the reservoir to
the hydraulic unit. Tap around the perimeter to
break the seal and separate the reservoir from the
motor assembly.
4. Remove the spring retaining screw from the suc-
tion tube.
5. Remove the suction tube and strainer by pulling
down and out.
6. Remove the four capscrews retaining the pump to
the drive motor.
7. Disassemble the pump assembly and coupling
from the adapter.
INSTALL
NOTE: The hydraulic unit includes four separate kits
as shown in Figure 4 or Figure 5.
1. Clean and lubricate all components using clean
hydraulic oil.
2. Replace all O-rings and seals within the unit.
3. Grease the coupler and coupler cavity with the
motor resting with the adapter plate up. Align the
pump mounting holes with the holes in the motor.
Ensure that the tank is seated into the motor.
4. Install the four capscrews and tighten to 13.6 to
16.3 N•m (10 to 12 lbf ft).
5. Install the O-rings into the pump cavities. Apply
grease to the return tubes. Insert tubes into pump
cavities and O-rings. Grease the suction tube and
insert into locking device with hole. Install and
tighten the spring retaining screw to secure the
suction tube.
6. Remove the retainer and replace the O-ring.
Lightly grease the O-ring before installation.
7. Align the reservoir so the hose connections will be
in the same position as they were prior to re-
moval. Install the four capscrews to retain the res-
ervoir.
8. Install the hydraulic unit. Refer to Hydraulic Unit -
Install, in this manual.
9. Remove the breather and fill the reservoir with the
recommended oil. See the section
Capacities
and Specifications 8000YRM1511, Hydraulic
Oils. Add oil until the oil is up to the full mark. If
too much oil is added, the oil will leak from the
breather during operation. If too much oil has
been added, drain the excess or use a suction de-
vice to remove some of the oil.
10. Run the pump for 5 seconds and energize the
lowering valve at the same time so that oil gets
through the pump body and valve at 0.0 psi. Op-
erate the forks up and down three or four times to
remove air from the system. Operate the lift truck
until the hydraulic oil reaches operating tempera-
ture. Remove the breather and check the hy-
draulic oil level. Add additional oil if necessary.
Check for hydraulic oil leaks.
11. Install the drive unit compartment cover. Test the
operation of the motorized hand truck before re-
turning the truck to service.
Hydraulic Pump 1900 YRM 1506
6