Toro 3505D Lawn Mower User Manual


 
Groundsmaster 3505--D Page 5 -- 17 Electrical System
High Temperature Shutdown Switch
The high temperature shutdown switch is located on the
water pump housing on the rearof the engine block (Fig.
20). The shutdown switch has a blue/white wire con-
nectedtoit.
The Standard Control Module monitors the operation of
the high temperature shutdown switch. If the ignition
switch is in the ON position (engine running) and the
high temperature shutdown switch c loses due to exces-
sive coolant temperature, the Module Over Tempera-
ture Shutdown input LED should illuminate and the
engine should shut down.
Testing
CAUTION
Make sure engine is cool before removing the
temperature switch.
1. Makesure ignition switchis in theOFF position.Low-
er coolant level in the engine and remove the tempera-
ture switch.
2. Put switch in a container of oil with a thermometer
and slowly heat the oil (Fig. 21).
CAUTION
Handle the hot oil w ith extreme care to prevent
personal injury or fire.
3. Check continuity of the switch with a multimeter
(ohms setting). The high temperature shutdown switch
is normally open and should close between 225 to
235
o
F (107 to 113
o
C).
4. Allow oil to cool while observing temperature. The
high temperatureshutdown switch should openat about
219
o
F (104
o
C).
5. Replace switch if specifications are not met.
6. 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. W ater pump housing 2. Shutdown switch
Figure 22
1
2
Figure 23
Electrical
System