Toro Groundsmaster 4100-D Service Manual page 219

Testing
1. Park machine on a level surface, lower cutting deck,
stop engine, engage parking brake and remove key
from the ignition switch.
2. Locate hydraulic valve solenoid coil to be tested (Fig.
38). Disconnect wire harness connector from coil.
3. Identify coil resistance specification by measuring
the coil diameter and coil height (Fig. 39).
NOTE: Prior to taking small resistance readings with a
digital multimeter, short the meter test leads together.
The meter will display a small resistance value (usually
0.5 ohms or less). This resistance is due to the internal
resistance of the meter and test leads. Subtract this val-
ue from from the measured value of the component you
are testing.
4. Using a multimeter (ohms setting), measure resis-
tance between the two (2) connector terminals on the
solenoid coil. The correct resistance for the solenoid coil
is identified in the chart below.
COIL COIL
DIAMETER HEIGHT
1.84 in 1.96 in
(46.7 mm) (49.9 mm)
1.41 in 1.43 in
(35.8 mm) (36.3 mm)
NOTE: Solenoid coil resistance should be measured
with solenoid at approximately 68
may be slightly different than listed at different tempera-
tures. Typically, a failed solenoid coil will either be
shorted (very low or no resistance) or open (infinite re-
sistance).
5. If solenoid coil resistance is incorrect, replace coil:
A. Remove nut securing solenoid coil to the car-
tridge valve. Carefully slide solenoid coil off the
valve.
B. Install new solenoid coil to the cartridge valve.
Install and torque nut 5 ft- -lb (6.7 N- -m). Over--tight-
ening may damage the solenoid coil or cause the
cartridge valve to malfunction.
6. After testing is completed, connect wire harness
connector to the solenoid coil.
Groundsmaster 4100--D/4110--D
COIL
RESISTANCE
7.1 ohm
8.8 ohm
o o
F (20 C). Resistance
Page 5 - - 33
Figure 39
4WD MANIFOLD
SHOWN
5 ft- -lb
(6.7 N- -m)
4
2
3
Figure 40
1. Hydraulic manifold
2. Cartridge valve
COIL
DIAMETER
COIL
HEIGHT
1
3. Solenoid coil
4. Nut
Electrical System