High Temperature Shutdown Switch - Toro Groundsmaster 4100-D Service Manual

High Temperature Shutdown Switch

The high temperature shutdown switch is located near
the glow plug connection on the engine cylinder head
(Fig. 38). There is a blue wire attached to the switch.
Testing
CAUTION
Make sure engine is cool before removing the
temperature switch.
1. Lower coolant level in the engine and remove the
temperature shutdown switch.
2. Put switch in a container of oil with a thermometer
and slowly heat the oil (Fig. 39).
CAUTION
Handle the hot oil with extreme care to prevent
personal injury or fire.
3. Check continuity of the switch with a multimeter
(ohms setting). The temperature switch is normally
open and should close between 225
o
113 C).
4. Allow oil to cool while observing temperature. The
temperature switch should open at about 219
o
(104 C).
5. Replace switch if necessary.
6. Install switch to the water flange.
A. Clean threads of cylinder head and switch thor-
oughly. Apply thread sealant to the threads of the
switch.
B. Screw switch into the cylinder head and tighten.
C. Connect blue wire to switch.
7. Fill engine cooling system (see Operator's Manual).
Groundsmaster 4100−D
1. Temp. shutdown switch
o o o
to 235 F (107 to
o
F
Page 5 − 25
2
1
Figure 38
2. Glow plug connection
VOA
Figure 39
Electrical System