Toro Groundsmaster 4000-D Service Manual page 83

Procedure for Cutting Deck Gear Pump Flow Test
NOTE: Over a period of time, the gears and wear plates
in the pump can wear. A worn pump will by pass oil and
make the pump less efficient. Eventually, enough oil loss
will occur to cause the cutting deck motors to stall under
heavy cutting conditions. Continued operation with a
worn, inefficient pump can generate excessive heat and
cause damage to the seals and other components in the
hydraulic system.
1. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine for approximately 10
minutes. Make sure the hydraulic tank is full.
2. Park machine on a level surface with the cutting
decks lowered and off. Make sure engine is off and the
parking brake is applied.
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. Locate deck manifold for gear pump section to be
tested. Disconnect hydraulic hose at deck manifold port
(P1) (Fig. 38).
4. Install tester in series with the the disconnected hose
and hydraulic manifold port (P1).
5. Make sure the flow control valve on the tester is fully
open.
6. Start engine and move throttle to full speed (2870
RPM). Do not engage the cutting decks.
IMPORTANT: Do not fully restrict oil flow through
tester. In this test, the flow tester is positioned be-
fore the relief valve. Pump damage can occur if the
oil flow is fully restricted.
7. Watch pressure gauge carefully while slowly closing
the flow control valve until 2000 PSI (138 bar) is ob-
tained. Verify with a phototac that the engine speed is
still 2870 RPM.
Groundsmaster 4000--D
8. Flow indication should be approximately 14 GPM (53
LPM).
9. Shut off engine and record test results.
10.Disconnect flow tester from hydraulic hose and man-
ifold port. Reconnect hose to the manifold.
11. If a pressure of 2000 PSI (138 bar) cannot be ob-
tained or flow was less than 11.5 GPM (44 LPM) (85%
of expected flow), check for restriction in the pump in-
take line. If line is not restricted, consider that gear pump
is worn or damaged.
RIGHT
FRONT
1. Front PTO manifold
2. Hyd. hose to front P1
Page 4 - - 49
1
4
2
Figure 38
3. LH PTO manifold
4. Hyd. hose to LH P1
Hydraulic System
3