JLG 660SJ Service Manual - Manual (Page 240)

SECTION 5 - HYDRAULICS
5-30 – JLG Lift – 3121202
5.7 PRESSURE SETTING PROCEDURES
COLD TEMPERATURES HAVE A SIGNIFICANT IMPACT ON PRES-
SURE READINGS. JLG INDUSTRIES, INC. RECOMMENDS OPER-
ATING THE MACHINE UNTIL THE HYDRAULIC SYSTEM HAS
WARMED TO NORMAL OPERATING TEMPERATURES PRIOR TO
CHECKING PRESSURES. JLG ALSO RECOMMENDS USING A CAL-
IBRATED GAUGE. PRESSURE READINGS ARE ACCEPTABLE IF
WITHIN +/- 5% OF SPECIFIED PRESSURES.
Main Relief, Steer, Swing and Lift Down
1. Install pressure gauge at quick disconnect on port
MP on main valve.
2. With the aid of an assistant, activate telescope in.
3. While monitoring pressure gauge, adjust main relief
to 3000 PSI (206.85 Bar).
4. With the aid of an assistant, activate steer left.
5. While monitoring pressure gauge, adjust steer left
relief to 1800 PSI (124.1 Bar).
6. With the aid of an assistant, activate steer right.
7. While monitoring pressure gauge, adjust steer right
relief to 1800 PSI (124.1 Bar).
8. With the aid of an assistant, activate swing left or
right.
9. While monitoring pressure gauge, adjust swing relief
to 1700 PSI (117.2 Bar).
10. With the aid of an assistant, activate lift down.
11. While monitoring pressure gauge, adjust lift down
relief to 1500 PSI (103.4 Bar)
.
Platform Level
1. Install pressure gauge at quick disconnect on port
M3 on main valve.
2. With the aid of an assistant, activate platform level
forward.
3. While monitoring pressure gauge, adjust platform
level relief to 2800 PSI (193.06 Bar).
4. Install pressure gauge at quick disconnect on port
M4 on main valve.
5. With the aid of an assistant, activate platform level
backward.
6. While monitoring pressure gauge, adjust platform
level relief to 1800 PSI (124.11 Bar).
Articulating Jib Boom (If Equipped)
1. Install pressure gauge at quick disconnect on articu-
lating valve.
2. With the aid of an assistant, activate articulating jib
up.
3. While monitoring pressure gauge, adjust articulating
jib up relief to 1500 PSI (103 Bar).
4. With the aid of an assistant, activate articulating jib
down.
5. While monitoring pressure gauge, adjust activate
articulating jib down relief to 1200 PSI (83 Bar).
Figure 5-28. Articulating Jib Boom Pressure
Adjustments