Toro Z Master Z400 Series Service Manual page 85

HYDRAULIC SYSTEM
5. Check the hydraulic reservoir and fill as needed with
Mobil 1 Extended Performance, 15w50 oil.
6. Disconnect the electric PTO clutch from the wiring
harness to prevent accidental engagement of the
mower deck.
7. Disconnect the seat switch from the harness.
Temporarily install a jumper wire across the harness
(Fig. 207). Move the seat back to the operating
position.
4
8. Verify the restrictor valve on the hydraulic flow tester
is in the fully "Opened" position.
9. Start the machine. Run the unit for approximately 5
minutes to warm the oil in the hydrostatic pumps.
10. Release the parking brake and bring both levers to
the inside neutral position. Run the engine at full
RPM.
4-20
Fig 207
PICT-0014a
11. Stroke the left hand hydrostatic lever fully forward.
Very slowly, rotate the "T" handle of the adjustable
flow tester restrictor valve until the pressure gauge
reaches 300 psi (21 bar). Record the measured flow
(gallons/liters per minute).
12. With the unit at full engine speed, slowly rotate the
"T" handle of the flow tester restrictor valve clock-
wise until the pressure gauge reads approximately
1000 to 1200 psi (69 to 83 bar).
CAUTION: DO NOT operate the machine for
extended period of time at high pressure.
13. Record the difference of "flow droop" of the pump.
For the Hydro-Gear 10A and BDP 12 pump,
maximum allowable "flow droop" is 1.5 gpm (6.8
liters/min). Any droop greater than 1.5 gpm (6.8
liters/min) is considered unacceptable and the pump
should be replaced, barring any other potential
causes for the pressure drop.
14. Return the motion control lever to neutral position
and return the levers to the neutral lock position.
Engage the parking brake. Slow the engine speed to
idle and turn the ignition switch to the OFF position.
15. Disconnect the hydraulic flow tester from the
hydraulic lines.
16. Reconnect the hydraulic lines to the wheel motor.
Tighten the fittings.
17. Tighten the hydraulic lines at the pump.
18. Check the hydraulic reservoir and fill as necessary to
the "HOT" level mark. See, Checking the Hydraulic
Fluid, page x-xx.
19. Reinstall the rear tire and lower the unit to the
ground. Remove the temporary jumper cable for the
seat and reconnect the seat switch. Reconnect the
electric PTO clutch connector.
Z Master Z400 Service Manual