Toro Groundsmaster 4100-D Service Manual page 93

Procedure for Cutting Deck Motor Case Drain
Leakage Test
NOTE: Over a period of time, a deck motor can wear in-
ternally. A worn motor may by--pass oil to its case drain
causing the motor to be less efficient. Eventually,
enough oil loss will cause the deck motor to stall under
heavy cutting conditions. Continued operation with a
worn motor can generate excessive heat and cause
damage to hydraulic system components.
NOTE: One method to find a failing or malfunctioning
deck motor is to have another person observe the ma-
chine while mowing in dense turf. A bad deck motor will
run slower, produce fewer clippings and may cause a
different appearance on the turf.
IMPORTANT: Mow circuit flow for the Groundsmas-
ter 4100/4110 is approximately 16 GPM (61 LPM).
Use 40 GPM Hydraulic Tester #AT40002 (pressure
and flow) for this test (see Special Tools in this
chapter).
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 engaged.
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.
NOTE: The wing deck motors are connected in series.
To isolate a faulty motor, both motors in the circuit may
have to be tested by starting with the left side motor first.
3. Disconnect return hose from the motor to be tested
(Fig. 42).
4. Install 40 GPM Hydraulic Tester #AT40002 (pres-
sure and flow) in series with the motor and the discon-
nected return hose. Use hydraulic hose kit (see Special
Tools in this chapter) to connect tester to machine. Make
sure the flow control valve on the tester is fully
open.
5. Disconnect the motor case drain hose (small diame-
ter hose) where it connects to the machine (not at the
motor). Put a steel cap on the fitting; leave the case drain
hose open.
Groundsmaster 4100--D/4110--D
6. After installing flow tester, start engine and run at idle
speed. Check for hydraulic leakage and correct before
proceeding with test.
Cutting deck blades will rotate with PTO switch
in ON position. Keep away from cutting deck dur-
ing test to prevent personal injury from rotating
blades. Do not stand in front of the machine.
7. Sit on seat and move throttle so engine is running at
high idle speed (2870 RPM). Move PTO switch to ON.
8. While watching pressure gauge, slowly close flow
control valve on tester until a pressure of 1200 PSI (83
bar) is obtained.
NOTE: Use a graduated container, special tool
TOR4077, to measure case drain leakage.
9. Have a second person measure flow from the case
drain line for 15 seconds, then move the PTO switch to
OFF. Open the tester flow control valve and stop the en-
gine. Record test results.
TEST RESULTS: Flow less than 22.4 ounces (662
ml) of hydraulic fluid in 15 seconds.
10.If flow is more than 22.4 ounces (662 ml) (0.7
GPM/2.6 LPM) in 15 seconds, the motor is worn or dam-
aged and should be repaired or replaced.
11. When testing is complete, disconnect tester and
hose kit from motor and machine hydraulic hose. Re-
connect hose to the deck motor. Remove cap from ma-
chine fitting and reconnect case drain hose.
12.If required, repeat test procedure for other deck mo-
tors.
1
2
1. Deck motor (RH shown)
2. Return hose
Page 4 - - 55
CAUTION
3
Figure 42
3. Case drain hose
Hydraulic System