Manitowoc MLC150-1, Service Maintenance Manual

Page: 44 / 206

HYDRAULIC SYSTEM MLC150-1 SERVICE/MAINTENANCE MANUAL
2-24
Published 03-21-2021, Control # 264-01
Servicing Suction Strainer
Each pump suction line is equipped with a suction strainer
located inside the hydraulic tank (
Figure 2-21 ).
Service the suction strainers when the fault
alarm comes on and the Suction Pressure icon
appears in the Fault Bar of the main display.
To service the suction strainers, the hydraulic tank must be
drained.
See Figure 2-21 for the following procedure.
1. Stop the engine and allow the hydraulic oil to cool.
2. Drain the hydraulic oil into a suitable container capable
of holding 416 L (110 gal).
3. Remove the access cover (1) from the hydraulic tank.
4. Using a pipe wrench, remove the suction strainers (2)
from the valve mounting plate (3).
5. Either replace the strainers with new ones or, if the
strainers are not damaged, clean them as follows:
a. Soak the suction strainers in a clean, nonflammable
solvent.
b. Brush off the outer surfaces.
c. Flush the strainers with solvent from the inside out.
6. Apply thread sealant to the suction strainer threads.
7. Thread the suctions strainers into the valve mounting
plates, and tighten with a pipe wrench.
8. Reinstall the access cover (1).
9. Fill the hydraulic tank with clean oil as instructed in
step 18 on page 2-25 .
10. Start the engine and check for leaks. Correct as needed.
Changing Hydraulic Oil
Unless otherwise specified, refer to Figure 2-17, page 18 for
the following procedure.
Drain and refill the hydraulic system semiannually or every
1,000 hours of engine operation, whichever comes first,
unless an alternate interval has been established through an
oil analysis program.
1. Operate the crane until the hydraulic oil is at its normal
operating temperature. This helps remove impurities
from the system.
2. Stop the engine.
3. Vent the tank using either the vent valve (8) or the
schrader valve (9).
4. Verify the shut-off valves (17) are open.
5. Place a suitable container capable of holding 416 L (110
gal) under the hydraulic tank.
6. Remove the dust cap from the quick-drain valve (20).
7. Insert the end of the hose from the quick-drain drainer
assembly (
Figure 2-22 ) in the container.
8. Connect the quick-drain drainer to the quick-drain valve
and completely drain the hydraulic tank. The quick-drain
drainer assembly is stored in the crane’s parts box.
Item Description
1 Access Cover
2 Suction Strainer (Qty 2)
3 Valve Mounting Plate (Qty 2)
FIGURE 2-21
View in Left Enclosure
REFERENCE
ONLY