Skyjack SJ519 TH, Service Manual, Page: 102 / 108

102
SJ519 TH 216942AC
Section 4 – Procedures Non-Routine Maintenance
Service Brake Pressure
▪
Service Brake Pressure Check:
1. Release residual pressure by moving the joystick
several times in each direction.
2. Remove plug and install a 1,500 psi gauge into
the GP2 port on the main manifold.
GP2 Test
Port
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3. With engine running at low idle, depress
brake pedal fully. Pressure should increase
proportionally to 1,000 psi MAX.
4. If maximum pressure is less than 1,000 psi,
brake valve must be replaced.
.
NOTE
The pressure setting value is the nominal maximum
value.
IMPORTANT
There is no adjustment. Replace the brake valve at
the service brake pedal.
Pilot Pressure
▪
Pilot Pressure Check:
1. Release residual pressure by moving the joystick
several times in each direction.
2. Install a 1,000 psi gauge into the fitting at port
SP1 (GP1) of the hydraulic function manifold.
3. With engine running at low idle and NO
hydraulic function engaged, pressure should be
350 ± 25 psi.
GP1 Test
Port
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Pilot Pressure Adjustment:
1. Locate RV6 on the drive pump and remove the
plug to access the spring and pop it. Hold the
relief main body to prevent it from loosening.
2. Inspect the seat area of the poppit for any
unusual wear, damage, or debris. If damaged
then the complete valve must be replaced