JLG 1850SJ, Service And Maintenance Manual, Page: 397 / 712

SECTION 5 - BASIC HYDRAULIC INFORMATION & HYDRAULIC SCHEMATICS
3121619 5-145
REPLACING CHARGE PUMP JOURNAL BEARINGS
Use a suitable press to remove and replace the journal bear-
ings. Refer to the drawings below for installation dimensions.
ASSEMBLY
1. Lubricate and install new seal (K150).
2. Install housing (K300). Install screws (K350). Using a 10
mm internal hex, torque screws per listing in table.
3. Install alignment pins (K450). Install new gasket (K151).
4. Lubricate and reassemble charge pump assembly [shaft
(K201), pin (S500), geroter (S100), cover (S200), two clips
(K205)].
5. Install charge pump assembly into housing in original
position.
6. Lubricate and install seal (S300).
7. Install aux pad (K101).
8. Using a 10 mm internal hex, install screws (K400). Torque
screws per listing in table.
9. Lubricate and install seal (K250). Install running cover
(K301).
10. Install screws (K351) and brackets (K975). Torque screws
per listing in the table.
Charge Check / HPRV
The high pressure relief and charge check valve assembly may
be removed for cleaning and replacement of the O-rings.
These valves are factory set and are not field adjustable. Refer
to the pump model code for the factory setting when ordering
replacements.
REMOVAL
1. Using an 8 mm internal hex wrench, remove the valve
seat plugs (K007).
2. Carefully lift the valve (H002) and spring (H003) assem-
blies from the center section using a magnet.
INSPECTION
1. Inspect the valves and mating seats in the valve seat
plugs (K007) for damage or foreign material.
REASSEMBLY
1. Lubricate and install new O-rings (K008, K010) and
backup ring (K009) on valve seat plug (K007).
2. Verify that the conical springs (H003) are properly
retained on the check relief valves (H002). Install the
valve assemblies into the center section. Ensure each
valve assembly moves freely in its bore.
3. Install the valve seat plugs into the center section and
torque to 80 Nm [59.lbft].
4. Operate machine through full range of controls to
ensure proper operation. Check for leaks.
Figure 5-137. Charge Check / HPRV