JLG 4017 Service Manual - Manual (Page 109)

8.9 4017
Hydraulic System
6. Drain the hydraulic oil reservoir. Refer to Section
8.5.1, “Hydraulic Oil Reservoir Draining.”
7. Thoroughly clean the pump (1) and surrounding
area, including all hoses and fittings before
proceeding.
Note: Cap all hoses as you remove them to prevent
unnecessary fluid spillage.
8. Remove the four bolts and four lockwashers
securing the flange halves to the pump. Remove the
inlet hose and o-ring.
Note: Before removing any fittings from the pump, note
their orientation to ensure correct installation.
9. Remove the four bolts and four lockwashers
securing the flange halves to the pump. Remove the
outlet hose and o-ring.
10. Disconnect the case drain hose from the fitting.
Disconnect the load sense line.
11. Remove the two bolts and two lockwashers securing
the pump to the transmission. Remove the gasket
located between the transmission and the pump.
Wipe up any hydraulic oil spillage.
Note: DO NOT disassemble the operating pump. The
pump is pre-set from the manufacturer. Any adjustments
or repairs performed by anyone other than an authorized
dealer could void the warranty.
b. Pump Installation
1. While the pump is still on the bench, install all
fittings, except the outlet hose fitting, orientating
them as noted during removal.
2. Place the pump and a new gasket into position on
the transmission. Align the pump shaft with the
internal transmission gear, so that the machined
teeth mesh together.
3. Align the bolt holes with the pump mount holes.
Secure the pump to the transmission with the two
bolts and washers.
4. If necessary, slide the T-bolt band clamp onto the pump
inlet hose. Uncap and secure the hose to the hydraulic
reservoir outlet connection with the T-bolt band clamp.
5. Place a new oiled o-ring into position over the pump
opening. Uncap and secure the inlet hose with two
flange halves, four lockwashers and four bolts.
6. Connect the load sense line to the fitting.
7. Place a new, oiled o-ring into position over the pump
opening. Uncap and secure the outlet hose with two
flange halves, four lockwashers and four bolts.
8. Fill the hydraulic reservoir with clean, filtered
hydraulic oil.
9. Prime the pump by filling the case drain port with fresh,
filtered hydraulic oil from a clean container before
installing the case drain connector and hose.
10. Check all routing of hoses and tubing for sharp
bends or interference with any rotating members. All
tube and hose clamps must be tight.
11. Start the engine and run at approximately one-third
to one-half throttle for about one minute without
moving the machine or operating any hydraulic
functions.
12. Inspect for leaks and check all fluid levels. The
hydraulic reservoir oil level must be to the middle of
the sight gauge.
c. Pump Test
Refer to Section 8.4.1, “Hydraulic Pressures.”
1. Check the system functions.
MZ0280
1
WARNING:
Hydraulic oil leaking under
pressure can penetrate the skin and cause
severe personal injury. DO NOT use your hand
or any part of your body to check for hydraulic
leaks. When checking for hydraulic leaks, wear
safety glasses and gloves to help provide
protection from spraying hydraulic oil. Use a
piece of cardboard or paper to search for
leaks.