JLG 1850SJ Service And Maintenance Manual page 387

Oil level in reservoir
Charge check / HPRVs
Low prime mover speed
Charge and control pressures
Air in system
Contaminated control orifices
Contaminated control screens
Pump inlet vacuum
3121619
SECTION 5 - BASIC HYDRAULIC INFORMATION & HYDRAULIC SCHEMATICS
Table 5-39. Sluggish system response
Item
Low oil level will cause sluggish response.
Incorrect pressure settings will affect system
reaction time.
Low engine speed will reduce system perfor-
mance.
Incorrect pressures will affect system perfor-
mance.
Air in system will produce sluggish system
response.
Control orifices are plugged.
Control screens are plugged.
Inlet vacuum is too high resulting in reduced
system pressure.
Description
Fill reservoir.
Replace charge check / HPRVs.
Adjust engine speed.
Measure and adjust charge and control pres-
sures.
Fill tank to proper level. Cycle system slowly for
several minutes to remove air from system.
Clean control orifices.
Clean or replace control screens.
Measure charge inlet vacuum. Inspect line for
proper sizing. Replace filter. Confirm proper
bypass operation.
Action
5-135