2-39. MAINTENANCE OF PRESSURE RELIEF VALVE 12253778-1 AND PRESSURE
RELIEF VALVE 12253778-2 (CONT).
ADJUSTMENT OF CHECK VALVE (CONT)
Adjust pressure for check valve (5) to
between 2100 and 2300 psi (14,480
and 15,859 kPa) by turning screw (6)
counterclockwise to decrease pressure or
clockwise to increase pressure.
When correct pressure adjustment is ob-
tained, tighten nut (4).
If correct pressure adjustment cannot be
obtained, replace check valve (5). Refer
to page 2-154.
ADJUSTMENT OF BOOM CYLINDER
PRESSURE RELIEF VALVE
1 Perform adjustment of check valve pro-
2 Loosen nut (1) on boom cylinder pres-
sure relief valve (2).
3 Adjust pressure for boom cylinder pres-
sure relief valve (2) to between 1950
and 2050 psi (13,445 and 14,135 kPa)
by turning screw (3) counterclockwise to
decrease pressure or clockwise to in-
4 When correct pressure is obtained,
tighten nut (1).
5 If correct pressure adjustment cannot be
obtained, replace boom cylinder pressure
relief valve (2). Refer to page 2-154.
6 Push BOOM cylinder control handle (4)
to LOWER until boom is in stowed
7 Turn off hydraulic system. Refer to TM