Service Manual

HYDRAULIC SYSTEM

4-35Z580/Z589 DFI Z Master Service Manual

7. Verify the restrictor valve on the hydraulic ow tester

is in the fully “Opened” position (Fig. 341).

10. Stroke the left hand hydrostatic lever fully forward.

Very slowly, rotate the “T” handle of the adjustable

ow tester restrictor valve until the pressure gauge

reaches 500 PSI (3447 kPa). The measured ow

should be 13 to 15 gpm (49 to 56.8 lpm) (Fig. 342).

Fig 341 PICT-3497a

Fig 342 PICT-3509a

11. With the unit at full engine throttle speed, slowly

rotate the “T” handle of the ow tester restrictor

valve clockwise until the pressure gauge reads

approximately 1000 to 1200 psi (6895 to 8274 kPa)

(Fig. 343).

Caution: DO NOT operate the machine for an ex-

tended period of time at the 1200 psi (8274 kPa)

rate.

8. Start the machine. Run it for approximately 5

minutes to warm the oil in the hydrostatic system.

9. Release the parking brake and bring both levers to

the inside neutral position. Set the engine throttle to

full RPM.

Fig 343 PICT-3509a