Coolant Temperature Sending Unit-Check And Replacement; Fluid Leakage - Jeep cherokee 1989 Owner's Manual

Chapter 3 Cooling, heating and air conditioning systems
5.8 The fan clutch is mounted with four nuts; two are
visible in this photo (arrows)
mounting screws, lift the shroud up until it clears the slots in the bottom
bracket of the radiator, then push the shroud over the fan.
8 Remove the nuts attaching the fanlclutch assembly to the water
pump hub or, on inline six-cylinder models, to the fan bearing hub (see
illustration).
9
Lift the fan/clutch assembly (and shroud, if necessary) out of the
engine compartment.
if necessary.
it
11 At this point, the fan may be unbolted from the clutch, if necessary.
If the fan clutch is stored, position it with the radiator side facing down.
1 2 Installation is the reverse of removal. Be sure to tighten the fan
and clutch mounting nuts evenly and securely.
Check
Electric fan
Refer to illustration 13
1 3 To test the motor, unplug the electrical connector at the motor
and use jumper wires to connect the fan directly t o the battery (see
illustration). If the fan still doesn't work, replace the fan motor.
1 4 If the motor tested OK, the fault lies in the coolant temperature
switch or the wiring which connects the components. Carefully check
all wiring and connections. If no obvious problems are found, further
diagnosis should be done by a dealer service department or repair shop.
The coolant temperature sending
unit on four-cylinder engines is located
near the left rear corner of the cylinder
head (arrow)
The Motor Manual Guy
5.13
jumper wires directly to the positive and negative terminals
of the battery
Mechanical fan with viscous clutch
15 Disconnect the negative battery cable and rock the fan back and
forth by hand t o check for excessive bearing play.
16 With the engine cold, turn the fan blades by hand. The fan should
turn freely.
1 7 Visually inspect for substantial fluid leakage from the clutch as-
sembly. If problems are noted, replace the clutch assembly.
18 With the engine completely warmed up, turn off the ignition switch
and disconnect the negative battery cable from the battery. Turn the
fan by hand. Some drag should be evident. If the fan turns easily,
replace the fan clutch.
6 Coolant temperature sending unit
Refer to illustrations 6. la, 6.16 and 6. I c
Warning: Wait until the engine i s completely cool before beginning this
procedure.
1 The coolant temperature indicator system is composed of a light
or temperature gauge mounted in the instrument panel and a coolant
temperature sending unit mounted on the engine (see illustrations).
Some vehicles have more than one sending unit, but only one is used
The coolant temperature sending
6. b
V6
unit on engines (arrow) is located
near the left front corner of the
intake manifold
Disconnect the fan electrical connector and run
be sure the clips don't touch each other
and create a short circuit
-
check and replacement
6. l c The coolant temperature sending
unit on inline six-cylinder engines is
located near the left rear corner of the
cylinder head (arrow)
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