Toro Groundsmaster 3280-D Service Manual page 284

Testing the High Temperature Shutdown Switch (continued)
Electrical System: Testing the Electrical Components
If the radiator or engine is hot, pressurized hot coolant can escape
and cause burns.
Do not open the radiator cap or drain the radiator when the coolant
is hot. Ensure that the engine is cool before removing the high
temperature shutdown switch from the engine.
3. Lower the coolant level in the engine.
4. Remove the wire harness connector from the high temperature shutdown
switch, and remove the switch from the engine.
g226814
5. Put the end of the switch in a container of oil with a thermometer and then
slowly heat the oil
The oil is hot and could cause personal injury or fire.
Handle the hot oil with extreme care.
6. Check the 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 between 107° and 113°C (225° and 235°F).
B. On the Groundsmaster 3320 (gasoline engine), the high temperature
shutdown switch should close at approximately 114°C (238°F).
7. Allow oil to cool while observing temperature.
A. On the Groundsmaster 3280-D (diesel engine), the high temperature
shutdown switch should open at approximately 104°C (219°F).
B. On the Groundsmaster 3320 (gasoline engine), the high temperature
shutdown switch should open at approximately 111°C (232°F).
8. If the switch does not meet the specifications, replace the switch.
DANGER
Figure 156
(Figure 156).
CAUTION
Page 6–56 Groundsmaster ® 3280-D/3320
05138SL Rev B