Toro Groundsmaster 4500-D, Руководство по обслуживанию

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Groundsmaster 4500--D/4700--D Page 5 -- 21 Electrical System (Rev. A)
Temperature Sender
The temperature sender is located near the alternator
on the water flange attached to the engine cylinder head
(Fig. 31). There is a gray wire attached to the terminal
of the switch.
Temperature Sender Test
1. Lower coolant level in the engine and remove the
temperature sender from water flange.
2. Put switch in a container of oil with a thermometer
and slowly heat the oil (Fig. 32).
CAUTION
Handle the hot oil with extreme care to prevent
personal injury or fire.
NOTE: Prior to taking resistance readings with a digital
multi meter, short the meter test leads together. The me-
ter will display a small resistance value (usually 0.5
ohms or less). This resistance is due to the internal re-
sistance of the meter and test leads. Subtract this value
from from the measured value of the component you are
testing.
3. Check resistance of the sender with a multimeter
(ohms setting) as the temperature increases.
A. The meter should indicate more than 600 ohms at
70
o
F (21
o
C).
B. The meter should indicate approximately 460
ohms at 100
o
F (38
o
C).
C. The meter should indicate from 54 to 78 ohms at
200
o
F (93
o
C).
D. Replace sender if specifications are not met.
4. Install sender to the water flange.
A. Clean threads of water flange and sender thor-
oughly. Apply thread sealant to the threads of the
sender.
B. Screw sender into the water flange. Torque send-
er from 16 to 20 ft--lb (21.7 to 27.1 N--m).
C. Reconnect gray wire to sender. Apply skin--over
grease (Toro Part No. 505--47) to sender terminal.
5. Fill engine cooling system (see Traction Unit Opera-
tor’s Manual).
Figure 31
1. Temperature sender 2. Alternator
1
2
Figure 32
VOA
Electrical System