High Temperature Shutdown Switch - Toro Groundsmaster 3280-D Service Manual

High Temperature Shutdown Switch

The high temperature shutdown switch is located on the
water pump housing. There is a blue/white wire at-
tached to the shutdown switch.
The Standard Control Module monitors the operation of
the high temperature shutdown switch. If the ignition
switch is in the ON position and the high temperature
shutdown switch has closed due to excessive coolant
temperature, the Module Over Temperature Shutdown
input LED should be illuminated and the engine should
shut down.
Testing
CAUTION
Make sure engine is cool before removing the
temperature switch from engine.
1. Lower the coolant level in the engine and remove the
high temperature shutdown switch from the engine.
2. Put the end of the switch in a container of oil with a
thermometer and slowly heat the oil (Fig. 16).
CAUTION
Handle the hot oil with extreme care to prevent
personal injury or fire.
3. Check resistance of the switch with a multimeter
(ohms setting) as the oil temperature increases. The
high temperature shutdown switch is normally open.
A. On the Groundsmaster 3280−D (diesel engine),
the high temperature shutdown switch should close
o
between 225 and 235
B. On the Groundsmaster 3320 (gasoline engine),
the high temperature shutdown switch should close
at approximately 238
4. Allow oil to cool while observing temperature.
A. On the Groundsmaster 3280−D (diesel engine),
the high temperature shutdown switch should open
at approximately 219
B. On the Groundsmaster 3320 (gasoline engine),
the high temperature shutdown switch should open
at approximately 232
5. Replace switch if specifications are not met.
Electrical System
o o o
F (107 and 113 C).
o o
F (114 C).
o o
F (104 C).
o o
F (111 C).
6. After testing is complete, install switch to the engine
housing.
A. Clean threads of housing and switch thoroughly.
Apply thread sealant to the threads of the switch.
B. Thread switch into the housing. Torque switch
from 16 to 20 ft−lb (21.7 to 27.1 N−m).
C. Reconnect wire to switch.
7. Fill engine cooling system (see Traction Unit Opera-
tor's Manual).
1. High temperature switch (gasoline engine)
1. High temperature switch (diesel engine)
Page 6 − 14
1
Figure 14
1
Figure 15
Figure 16
Groundsmaster 3280−D/3320