Toro Greensmaster TriFlex 3320/3420 Service Manual page 95

The steering/lift circuit gear pump flow test should be
performed to make sure that the steering, lift and trac-
tion charge circuits have adequate hydraulic flow.
Procedure for Steering/Lift Circuit Gear Pump Flow
Test:
1. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine for approximately ten
(10) minutes.
2. Park machine on a level surface with the cutting units
lowered. Make sure engine is off and the parking brake
is engaged. Make sure the hydraulic tank is full.
CAUTION
Prevent personal injury and/or damage to equip-
ment. Read all WARNINGS, CAUTIONS and Pre-
cautions for Hydraulic Testing at the beginning
of this section.
3. Thoroughly clean junction of hydraulic hose and dis-
charge (lower) fitting of gear pump (Fig. 25). Disconnect
hose from pump fitting.
4. Install hydraulic tester (pressure and flow) in series
with the gear pump fitting and the disconnected hose.
Make sure that tester flow arrow points from the pump
discharge and toward the disconnected hose. Also,
make sure flow control valve on the tester is fully
open.
5. Make sure that traction pedal and joystick are in neu-
tral and the parking brake is engaged.
6. Start engine and run at low idle speed. Check for hy-
draulic leakage and correct before proceeding with test.
7. Move throttle so engine is running at high idle speed.
Greensmaster 3320/3420
IMPORTANT: Do not fully restrict oil flow through
tester. In this test, the flow tester is positioned be-
fore the circuit relief valve. Pump damage can occur
if the oil flow is fully restricted.
8. Watch flow and pressure gauge carefully while slow-
ly closing the flow control valve on the tester until the
pressure gauge reads 800 PSI (55.2 bar).
9. Open control valve on tester, move throttle to low idle
speed and shut off engine. Record test results.
10.Flow gauge reading for a gear pump in good condi-
tion should be approximately 3.6 GPM (13.6 LPM).
11. If gear pump flow is less than 3.1 GPM (11.7 LPM),
check for restriction in the pump intake line. If no restric-
tion is found, repair or replace gear pump.
12.When testing is complete, disconnect tester from the
gear pump fitting and hydraulic hose. Connect hose to
pump fitting.
1
1. Gear pump
Page 5 - - 41
2
Figure 25
2. Hydraulic hose
Hydraulic System