Service Manual

Groundsmaster 7200/7210 Page 5 - 25 Electrical System
High Temperature Shutdown Switch
The high temperature shutdown switch is located on the
water pump housing (Fig. 32). The high temperature
shutdown switch is normally open and closes when en-
gine coolant temperature reaches approximately 240
o
F
(115
o
C). When excessive engine coolant temperature
causes the shutdown switch to close, the engine shuts
down. There is a blue/white wire attached to the shut-
down switch.
The Standard Control Module (SCM) monitors the op-
eration of the high temperature shutdown switch. If ex-
cessive engine coolant temperature causes the high
temperature shutdown switch to close, the High Tem-
perature Shutdown L ED on the SCM will be illuminated.
Theswitchanditscircuitwiringshould be tested using
the SCM before performing the following testing proce-
dure.
Testing
1. Park machine on a level surface, lower cutting deck
(or implement), stop engine, apply parking brake and re-
move key from ignition switch. Open hood to gain ac-
cess to engine.
CAUTION
Make sure engine is cool before removing the
high temperature shutdown switch from engine.
Do not open radiator cap or drain coolant if the
radiator or engine is hot. Pressurized, hot cool-
ant can escape 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. 33).
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
should close from 234
o
to 244
o
F(112
o
to 118
o
C).
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 (29.4 to 39.2 N- m).
C. Reconnect harness wire to shutdown switch.
7. Fill engine cooling system.
8. Lower and secure hood.
1. High temperature shutdown switch
Figure 32
1
Figure 33
Electrical
System