JLG Skytrak 6036 Service Manual page 187

Section 9. Hydraulic System
Trouble
Steers too Slowly
Front or Rear Wheels
Not Parallel in 2- or 4-
Wheel Steering
Steering is Spongy or
Noisy
Auxiliary Equipment
Slow or Malfunctions
Auxiliary Equipment
Drifts or Creeps
Tandem Pump Fails to
Deliver Fluid
Model 6036 S/N 9B0499 and Before
Probable Cause
Steer relief valve not set
correctly
Defective sequence valve
Steering cylinder leakage
Wheel misalignment
External leakage in system
Internal leakage in cylinder
Internal leakage in power
steering unit
Defective steer select valve
Air in steering lines
Faulty power steering unit
External fluid leakage at
tubes, hoses or fittings
Faulty relief valve setting
Internal leakage in cylinder
Internal leakage in control
valve
Defective tandem pump
Leakage in auxiliary
cylinder(s)
Low level in reservoir
Filler/breather on reservoir
is dirty
Suction strainer clogged
Suction line is restricted or
loose
Remedy
Check and set relief valve (para 9.1.6).
Install new cartridge or replace valve (para 9.3.5).
Install cylinder seal kit(s) (para 9.2.6).
Check and adjust wheel alignment as needed per
paragraph 5.2.5.
Check and tighten connections at valves, pump
and cylinders. Repair or replace defective hose.
Install cylinder seal kit(s) (para 9.2.6).
Repair or replace power steering unit.
Replace steer select valve (para 9.3.4).
Check and tighten loose connections. Operate
steering to purge system of air.
Repair or replace power steering unit.
Check and tighten connections at valves, pumps
and cylinders. Repair or replace faulty hose(s).
Check and set frame tilt relief valve (para 9.1.4).
Repair cylinder as required (para 9.2.7).
Repair control valve as required (para 9.3.1).
Repair tandem pump (para 9.4.1).
Repair or replace cylinder(s) or check valve (para
9.2.7).
Check and fill hydraulic reservoir as described in
Owners/Operators manual.
Clean or replace filler/breather.
Clean strainer as described in Owners/Operators
manual.
Clean or replace suction line and/or tighten if
loose.
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