Toro Groundsmaster 4100-D Service Manual page 107

Procedure for Engine Cooling Fan Circuit Gear
Pump Flow Test
1. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine under load for
approximately ten (10) minutes. Make sure the hydrau-
lic tank is full.
2. Park machine on a level surface with the cutting deck
lowered and off. Make sure engine is off and the parking
brake is applied. Raise and support seat.
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 fitting and hydraulic
hose at the last gear pump section which supplies the
engine cooling fan circuit (Fig. 50).
4. With the engine off and cutting deck lowered, discon-
nect the hydraulic hose from the 90
gear pump section.
IMPORTANT: Make sure that the oil flow indicator
arrow on the flow gauge is showing that the oil will
flow from the pump section, through the tester and
into the hydraulic hose.
5. Install tester with pressure gauge and flow meter in
series between the fitting and the disconnected hose.
Make sure the flow control valve on the tester is fully
open.
6. After installing tester, start engine and run at idle
speed. Check for hydraulic leakage at tester location
and correct before proceeding with test.
IMPORTANT: The pump is a positive displacement
type. If pump flow is completely restricted or
stopped, damage to the pump, tester or other com-
ponents could occur.
Groundsmaster 4100--D/4110--D
7. Move throttle so engine is running at high idle speed
(2870 RPM). DO NOT engage the cutting deck.
8. While watching tester pressure gauge, slowly close
flow control valve until 1000 PSI (69 bar) is obtained on
pressure gauge. Verify engine speed continues to be
2870 RPM.
NOTE: If engine speed drops below 2870 RPM during
testing, expect pump flow to decrease.
9. Open the tester flow control valve and stop the en-
gine. Record test results.
10.If a pressure of 1000 PSI (69 bar) could not be ob-
tained or flow is lower than 6 GPM (23 LPM), check for
restriction in pump intake line. If intake line is not re-
stricted, consider that gear pump is worn or damaged.
11. When testing is complete, remove tester and recon-
nect hose to pump fitting.
o
fitting in the last
1. Gear pump
2. Fan drive manifold
Page 4 - - 69
GAUGE READING TO BE: Flow approximately 7
GPM (26 LPM) at 1000 PSI (69 bar).
2
4
3
Figure 50
RIGHT
FRONT
1
3. Cooling fan supply hose
o
4. 90 fitting
Hydraulic System