Toro Groundsmaster 4100-D Service Manual page 77

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, inefficient motor can generate excessive heat,
cause damage to seals and other components in the hy-
draulic system, and affect quality of cut.
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.
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 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. 28). Install flow tester in series with the motor and
the disconnected return hose. Make sure the flow con-
trol valve on tester is fully open.
4. 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 (Fig. 29).
5. After installing flow tester, start engine and run at idle
speed. Check for hydraulic leakage and correct before
proceeding with test.
CAUTION
Cutting deck blades will rotate with PTO switch
in ON position. Keep away from cutting decks
during test to prevent personal injury from rotat-
ing blades. Do not stand in front of the machine.
Groundsmaster 4100--D
6. Sit on seat and operate the engine at full speed (2730
+ 30 RPM). Move PTO switch to ON.
7. While watching pressure gauge, slowly close flow
control valve on tester until a pressure of 1200 PSI is ob-
tained.
NOTE: Use a graduated container, special tool
TOR4077, to measure case drain leakage (Fig. 29).
8. Have another 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 0.7 GPM (less than
22.4 ounces (662 ml) of hydraulic fluid in 15 sec-
onds).
9. If flow is more than 0.7 GPM, the motor is worn or
damaged and should be repaired or replaced.
10.Disconnect tester from motor and hose. Reconnect
hose to the deck motor. Remove cap from machine fit-
ting and reconnect case drain hose.
11. If required, repeat test procedure for other deck mo-
tors.
2
1. Deck motor (RH shown)
2. Return hose
Rev. F
Page 4 - - 35
1
Figure 28
3. Case drain hose
Figure 29
Hydraulic System
3