Engine Temperature Sender - Toro Reelmaster 7000 Service Manual

Engine Temperature Sender

The engine temperature sender is located near the al-
ternator on the water flange attached to the engine cylin-
der head (Fig. 57). There is a gray wire attached to the
terminal of the sender.
The resistance of the temperature sender reduces as
the engine coolant temperature increases. The chang-
ing resistance of the temperature sender signals the
console temperature gauge to indicate engine coolant
temperature during machine operation.
Engine Temperature Sender Test
1. Park machine on a level surface, lower cutting units,
stop engine, apply parking brake and remove key from
ignition switch. Open hood to gain access to engine.
CAUTION
Make sure engine is cool before removing the
temperature sender from engine.
2. Lower coolant level in the engine and remove the
temperature sender from water flange.
3. Put sender in a container of oil with a thermometer
and slowly heat the oil (Fig. 58).
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.
4. Check resistance of the sender with a multimeter
(ohms setting) as the temperature increases. Replace
sender if specifications are not met.
OIL TEMP TEMP SENDER RESISTANCE
o o
100 F (38 C) 460 ohms (approximate)
o o
160 F (71 C) 140 ohms (approximate)
o o
200 F (93 C) 54 to 78 ohms
o o
221 F (105 C) 50 ohms (approximate)
Reelmaster 7000
5. 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 (22 to 27 N- -m).
C. Connect gray wire to sender. Apply skin--over
grease (Part Number TOR50547) to sender termi-
nal.
6. Fill engine cooling system.
7. Close and secure hood.
1. Temperature sender
Page 5 - - 39
1
2
Figure 57
2. Alternator
Figure 58
Electrical System