High Temperature Shutdown Switch - Toro Reelmaster 5210 Service Manual

High Temperature Shutdown Switch

The high temperature shutdown switch is located on the
water pump housing (Fig. 55). The high temperature
shutdown switch is normally open and closes when en-
gine coolant temperature reaches approximately 239
o
(115 C). When excessive coolant temperature causes
the shutdown switch to close, the engine shuts down.
There is a tan wire attached to the shutdown switch.
NOTE: If excessive coolant temperature causes en-
gine shutdown, the operator can restart the engine to al-
low the machine to be moved a short distance. After a
restart in this condition, the engine will run for approxi-
mately 10 seconds before the engine shuts down again.
The Electronic Control Module (ECM) monitors the op-
eration of the high temperature shutdown switch. The
switch and its circuit wiring should be tested as an ECM
input with the Diagnostic Display (see Special Tools and
Troubleshooting in this chapter).
If excessive coolant temperature caused the ECM to
shut down the engine, the Diagnostic light can be used
to identify the fault (see Diagnostic Light in the Trouble-
shooting section of this chapter).
Testing
1. Park machine on a level surface, lower cutting units,
stop engine, apply parking brake and remove key from
ignition switch. Open hood to gain access to engine.
CAUTION
Make sure engine is cool before removing the
temperature switch from engine.
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. 56).
CAUTION
Handle the hot oil with extreme care to prevent
personal injury or fire.
4. Check resistance of the switch with a multimeter
(ohms setting) as the oil temperature increases. The
high temperature shutdown switch is normally open and
o
should close from 234
Electrical System
o o o
to 244 F (112 to 118 C).
5. Replace shutdown switch if specifications are not
met.
6. After testing is complete, install shutdown switch to
o
F
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 39 N- -m).
C. Reconnect harness wire to switch.
7. Fill engine cooling system.
8. Lower and secure hood.
1. High temperature switch
Page 5 - - 42
1
Figure 55
Figure 56
Reelmaster 5010 Series