JLG Skytrak 6036 Service Manual page 160

Disassembly
1. Remove the relief valve from the control valve
housing.
2. Unscrew plug (1, Fig. 9.25) and remove the
relief valve cartridge from housing (8).
3. Remove and discard O-ring (9) from housing.
4. Remove acorn nut (19) and jam nut (17) from
adjustment screw (15).
5. Remove and discard O-rings (16 and 18).
6. Unscrew adjustment screw (15) from plug (1).
7. Invert the plug. Pilot spring (14) and poppet
(13) should drop out.
8. Remove O-rings (10 and 12) and backup ring
(11) from the plug.
9. Remove piston spring (2), piston (3) and relief
valve poppet (4) from check valve poppet (7).
10. Remove and discard O-ring (5) and backup
ring (6) from the relief valve poppet.
Cleaning and Drying
Clean metal parts in an approved solvent such as
trichlorethylene and blow dry.
Inspection and Replacement
1. Inspect the poppet seating surfaces. They
must be sharp, clean, and free of nicks or
excessive wear. Replace the part if worn or
damaged.
2. Install new O-rings and backup rings. Repair
kits are available.
3. Clean out the channel in piston (3, Fig. 9.25)
through which fluid passes.
4. Make sure the piston moves freely in the relief
valve poppet.
Assembly
1. Lubricate with hydraulic oil and install new O-
ring (5, Fig. 9.25) and backup ring (6) on relief
valve poppet (4). Stretch O-ring, do not roll it
to fit.
2. Lubricate poppet (4) with hydraulic oil and
insert into check valve poppet (7) followed by
piston (3) and piston spring (2).
3. Lubricate with hydraulic oil and install new O-
ring (10), backup ring (11) and O-ring (12) on
plug (1). Stretch O-rings, do not roll them to
fit.
4. Lubricate exterior of plug (1) and insert into
poppet (7).
9-47
Section 9. Hydraulic System
9
8
7
6
5
4
3
2
10
1. Plug
2. Pilot Spring
3. Piston
4. Relief Valve Poppet
5. O-ring
6. Backup Ring
7. Check Valve Poppet
8. Housing
9. O-ring
10. O-ring
11. Backup Ring
12. O-ring
13. Pilot Poppet
14. Pilot Spring
15. Adjustment Screw
16. O-ring
17. Jam Nut
18. O-ring
19. Acorn Nut
Fig. 9.25 Relief Valve Exploded View
Model 6036 S/N 9B0499 and Before
11
12
1
13
14
15
16
17
18
19
MA0661