D. Hydraulic System
Thoroughly review description of hydraulic system.
Use logical steps to determine cause of malfunction.
Identify the function or functions that require troubleshooting.
If possible, trace malfunction to source: pump, control, motor or cylinder.
Determine if pressure or volume is inadequate for function as specified:
Hydraulic System Pressures
Auxiliary circuits, gear pump 2800 p.s.i.
Main circuit, hydrostatic pumps 4350 p.s.i.
Hydraulic System Flows
Auxiliary circuits, gear pump 10 g.p.m.
Main circuit, hydrostatic pumps 13 g.p.m. each
(Flow determined at engine r.p.m. = 2900)
Worn or Malfunctioning pump or
motor
Stuck relief valve cartridge.
Low system pressure caused by
worn pump.
Air in system due to low level of
oil, cavitating pump, leaky
fittings, pinched hose, etc.