user manual

Groundsmaster 4100--DPage 5 -- 28Electrical System
Temperature Sender
The temperature sender is located near the alternator
onthewaterflangeattachedtotheenginecylinderhead
(Fig. 41). The resistance of the temperature sender re-
duces as the engine coolant temperature increases.
There is a gray harness wireattachedto the terminal of
the switch.
Testing
1. Lower coolant level in the engine and remove the
temperature sender from water flange.
2. Suspendsenderinacontainerofoilwithathermom-
eter and slowly heat the oil (Fig. 42).
CAUTION
Handle the hot oil with extreme care to prevent
personal injury or fire.
NOTE: Priorto takingresistancereadings withadigital
multimeter,shortthemetertestleadstogether.Theme-
ter will display a small resistance value (usually 0.5
ohms or less). This resistance is due to the internal re-
sistanceof themeter andtest leads.Subtract thisvalue
fromfromthemeasuredvalueofthecomponentyouare
testing.
3. Check resistance of the sender with a multimeter
(ohms setting) as the temperature increases. Replace
sender if specifications are not met.
COOLANT TEMP
TEMP SENDER RESISTANCE
100
o
F(38
o
C) 460 ohms ( approximate)
160
o
F(71
o
C) 140 ohms ( approximate)
200
o
F(93
o
C) 54 to 78 ohms
221
o
F (105
o
C) 50 ohms (approximate)
4. After testing is complete, install sender to the water
flange.
A. Thoroughly clean threads of water flange and
sender. Apply thread sealant to the threads of the
sender.
B. Screwsenderintothewaterflange.Torquesend-
er from 16 to 20 ft--lb (22 to 27 N--m).
C. Reconnect gray harness wire to sender. Apply
skin--overgrease (ToroPart No.505--165)tosender
terminal.
5. Fill engine cooling system.
Figure 41
1. Temperature sender 2. Alternator
1
2
Figure 42