High Temperature Shutdown Switch (Machines Without Operator Cab) - Toro Groundsmaster 360 Service Manual

High Temperature Shutdown Switch (Machines without Operator Cab)

The high temperature shutdown switch is located on the
water pump housing (Fig. 66). The high temperature
shutdown switch is normally open and closes when en-
gine coolant temperature reaches approximately 240
o
(115 C). If excessive engine coolant temperature
causes the shutdown switch to close, the engine shuts
down. There is a red wire attached to the shutdown
switch.
On 2WD machines, the Standard Control Module
(SCM) monitors the operation of the high temperature
shutdown switch. If the high temperature shutdown
switch closes (excessive engine coolant temperature),
the SCM high temperature warning LED should be illu-
minated.
On 4WD machines, the Toro Electronic Controller (TEC)
monitors the operation of the high temperature shut-
down switch.
Before performing the following testing procedure, the
temperature shutdown switch and its circuit wiring
should be tested as an electrical input using the SCM
on 2WD machines or the Diagnostic Display on 4WD
machines (see Standard Control Module or Diagnostic
Display in the Troubleshooting section of this chapter).
Testing
1. Park machine on a level surface, lower cutting deck,
stop engine, apply parking brake and remove key from
ignition switch. Raise and support hood.
CAUTION
Make sure engine is cool before removing the
temperature warning switch from engine. Do not
open radiator cap or drain coolant if the radiator
or engine is hot. Pressurized, hot coolant can es-
cape and cause burns.
2. Lower the coolant level in the engine and remove the
high temperature shutdown switch from the engine.
3. Put the end of the switch in a container of oil with a
thermometer and slowly heat the oil (Fig. 67).
CAUTION
Handle the hot oil with extreme care to prevent
personal injury or fire.
Groundsmaster 360
4. Check resistance of the switch with a multimeter
(ohms setting) as the oil temperature increases. The
high temperature shutdown switch is normally open
o
F (high resistance) and should close (continuity) from
o o
234 to 244 F (112
5. Replace shutdown switch if specifications are not
met.
6. After testing is complete, install shutdown 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 22 to 28 ft- -lb (30 to 38 N- -m).
C. Connect wire harness connector to shutdown
switch.
7. Fill engine cooling system. Lower and secure hood.
1
1. High temperature shutdown switch
Page 5 - - 49
o o
to 118 C).
Figure 66
Figure 67
Electrical System