thermostat MITSUBISHI LANCER 2005 Workshop Manual

14-1
GROUP 14
ENGINE COOLING
CONTENTS
GENERAL INFORMATION . . . . . . . .14-2
SERVICE SPECIFICATIONS . . . . . . .14-2
LUBRICANT . . . . . . . . . . . . . . . . . . . .14-2
SEALANTS . . . . . . . . . . . . . . . . . . . .14-3
SPECIAL TOOLS . . . . . . . . . . . . . . . .14-3
TROUBLESHOOTING . . . . . . . . . . . .14-5
INSPECTION CHART FOR TROUBLE
SYMPTOMS . . . . . . . . . . . . . . . . . . . . . . . . 14-5
INSPECTION PROCEDURE FOR
TROUBLE SYMPTOMS . . . . . . . . . . . . . . . 14-6
ON-VEHICLE SERVICE . . . . . . . . . . .14-22
ENGINE COOLANT LEAK CHECK . . . . . . 14-22
RADIATOR CAP VALVE OPENING
PRESSURE CHECK . . . . . . . . . . . . . . . . . . 14-22
ENGINE COOLANT REPLACEMENT . . . . 14-22
CONCENTRATION MEASUREMENT . . . . 14-23COOLING FAN MOTOR DRIVE CONTROL
UNIT CHECK . . . . . . . . . . . . . . . . . . . . . . . . 14-23
FAN CONTROL RELAY CONTINUITY
CHECK . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-24
COOLING FAN MOTOR CHECK . . . . . . . . 14-25
THERMOSTAT . . . . . . . . . . . . . . . . . .14-26
REMOVAL AND INSTALLATION . . . . . . . . 14-26
INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . 14-27
WATER PUMP . . . . . . . . . . . . . . . . . .14-29
REMOVAL AND INSTALLATION <4G1> . . 14-29
REMOVAL AND INSTALLATION <4G6> . . 14-30
WATER HOSE AND WATER PIPE . .14-31
REMOVAL AND INSTALLATION <4G1> . . 14-31
REMOVAL AND INSTALLATION <4G6> . . 14-33
INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . 14-34
RADIATOR . . . . . . . . . . . . . . . . . . . . .14-35
REMOVAL AND INSTALLATION . . . . . . . . 14-35

GENERAL INFORMATION
ENGINE COOLING14-2
GENERAL INFORMATION
M1141000100371The cooling system is designed to keep every part of
the engine at appropriate temperature in whatever
condition the engine may be operated. The cooling
method is of the water-cooled, pressure forced
circulation type in which the water pump pressurizes
coolant and circulates it throughout the engine. If the
coolant temperature exceeds the prescribed temperature, the thermostat opens to circulate the
coolant through the radiator as well so that the heat
absorbed by the coolant may be radiated into the air.
The water pump is of the centrifugal type and is
driven by the alternator drive belt from the
crankshaft. The radiator is the corrugated fin, down
flow type.
SERVICE SPECIFICATIONS
M1141000300416
LUBRICANT
M1141000400338
ItemSpecification
Radiator Performance kJ/h 4G13 Standard vehicles 137,720
Vehicles with capacity up radiator
(option)161,288
4G18 Standard vehicles 161,288
Vehicles with capacity up radiator
(option)181,800
4G63 181,800
A/T oil cooler Performance kJ/h 5,651
Item Standard value Limit
High-pressure valve opening pressure of radiator cap kPa 93 − 123 Minimum 83
Range of coolant antifreeze concentration of radiator % 30 − 60 -
Thermostat Valve opening temperature of
thermostat °C4G1 88 ± 1.5 -
4G6 82 ± 1.5 -
Full-opening temperature of
thermostat °C4G1 100 -
4G6 95 -
Valve lift mm 8.5 or more -
Item Specified coolant Quantity L
Engine coolant (including
condense tank)DIAQUEEN SUPER LONG LIFE COOLANT
or an equivalent4G1 5.0
4G6 7.0

SEALANTS
ENGINE COOLING14-3
SEALANTS
M1141000500324
SPECIAL TOOLS
M1141000600246
Item Specified sealant
Cylinder block drain plug 3M Nut Locking Part No.4171 or equivalent
Water pump <4G1>, Thermostat case
<4G6>, Cooling water outlet hose fitting
<4G6>MITSUBISHI GENUINE Part No.MD970389 or equivalent
Tool Number Name Use
MB991502 MUT-II sub assembly Reading diagnosis code
B991502

ON-VEHICLE SERVICE
ENGINE COOLING14-23
5. Apply the designated sealant to the screw area of
the cylinder block drain plug, and then tighten to
the standard torque.
Specified sealant: 3M Nut Locking Part
No.4171 or equivalent
Tightening torque:
40 ± 5 N⋅m <4G1>
44 ± 5 N⋅m <4G6>
6. Securely tighten the drain plug of the radiator.
7. Reinstall the radiator condenser tank.
CAUTION
Do not use alcohol or methanol anti-freeze or any
engine coolants mixed with alcohol or methanol
anti-freeze. The use of an improper anti-freeze
can cause corrosion of the aluminium
components.
8. By referring to the section on coolant, select an
appropriate concentration for safe operating
temperature within the range of 30 to 60%. Use
special tool LLC changer (MB991871) to refill the
coolant. A convenient mixture is a 50% water and
50% antifreeze solution (freezing point: −31°C).
Recommended antifreeze: DIAQUEEN SUPER
LONG LIFE COOLANT or equivalent
Quantity:
5.0 L <4G1>
7.0 L <4G6>
NOTE: For how to use special tool MB991871,
refer to its manufacturer’s instructions.9. Reinstall the radiator cap.
10.Start the engine and let it warm up until the
thermostat opens.
11.After repeatedly revving the engine up to 3,000
r/min several times, then stop the engine.
12.Remove the radiator cap after the engine has
become cold, and pour in coolant up to the brim.
Reinstall the cap.
CAUTION
Do not overfill the radiator condenser tank.
13.Add coolant to the radiator condenser tank
between the "F" and "L" mark if necessary.
CONCENTRATION MEASUREMENTM1141001100352
Measure the temperature and specific gravity of the
engine coolant to check the antifreeze concentration.
Standard value: 30 − 60% (allowable
concentration range)
Recommended antifreeze: DIAQUEEN SUPER
LONG LIFE COOLANT or equivalent
CAUTION
If the concentration of the anti-freeze is below
30%, the anti-corrosion property will be
adversely affected. In addition, if the
concentration is above 60%, both the
anti-freezing and engine cooling properties will
decrease, affecting the engine adversely. For
these reasons, be sure to maintain the
concentration level within the specified range.
COOLING FAN MOTOR DRIVE CONTROL
UNIT CHECK
M1141006100216
1. Remove the cooling fan motor drive control unit
connector.
2. Turn the ignition switch to the "ON" position, and
measure the voltage between terminal 1 and 3 at
the harness side connector.
Standard value: system voltage
AC200625
Cylinder block
drain plug
AC
AC303612AB
MB991871
AIR HOSE
AC103195
Y1716AU
1 23
AC
Cooling fan motor
drive control unit

THERMOSTAT
ENGINE COOLING14-26
THERMOSTAT
REMOVAL AND INSTALLATIONM1141002400442
Pre-removal and Post-installation Operation
•Engine Coolant Draining and Refilling (Refer to P.14-22).
•Air Cleaner Assembly Removal and Installation (Refer to
GROUP 15 P.15-3).
•Battery Removal and Installation
AC203409AC
4
3 6 7
22 ± 4 N·m
<4G1>
AC301429
1
2
36 7
13 ± 2 N·m
AD
5
<4G6>

THERMOSTAT
ENGINE COOLING14-27
REMOVAL SERVICE POINT
<> RADIATOR LOWER HOSE
DISCONNECTION
Make mating marks on the radiator lower hose and
the hose clamp. Disconnect the radiator lower hose.
INSTALLATION SERVICE POINTS
>>A<< THERMOSTAT INSTALLATION
CAUTION
Make absolutely sure that no oil adheres to the
rubber ring of the thermostat. Also do not fold or
scratch the rubber ring during installation.
Install the thermostat so that the jiggle valve is facing
straight up. Be careful not to fold or scratch the
rubber ring.
>>B<< RADIATOR LOWER HOSE
CONNECTION
1. Insert radiator lower hose as far as the projection
of the Cooling water inlet hose fitting.
2. Align the mating marks on the radiator lower hose
and hose clamp, and then connect the radiator
lower hose.
INSPECTIONM1141002500427
THERMOSTAT CHECK
1. Immerse the thermostat in water, and heat the
water while stirring. Check the thermostat valve
opening temperature.
Standard value:
88 ± 1.5°C <4G1>
82 ± 1.5°C <4G6>
Removal steps
1. Water temperature gauge unit
connector <4G6>
2. Water temperature sensor unit
connector <4G6>
<> >B<<3. Radiator lower hose connection4. Engine control oxygen sensor
connector and connector bracket
<4G1>
5. Control wiring harness clip <4G6>
6. Cooling water inlet hose fitting>>A<<7. ThermostatRemoval steps (Continued)
AC200641AC
Mating marks
AC000279
Jiggle valve
Rubber ring
AB
AC200642
Mating marks
Projection
Cooling water inlet
hse fitting
AH
ACX00400
AB

THERMOSTAT
ENGINE COOLING14-28
2. Check that the amount of valve lift is at the
standard value when the water is at the
full-opening temperature.
NOTE: Measure the valve height when the
thermostat is fully closed, and use this
measurement to compare the valve height when
the thermostat is fully open.
Standard value:
100°C <4G1>
95°C <4G6>
Amount of valve lift: 8.5 mm or more
ACX00401AC
Valve lift

WATER HOSE AND WATER PIPE
ENGINE COOLING14-31
WATER HOSE AND WATER PIPE
REMOVAL AND INSTALLATION <4G1>M1141003300415
Pre-removal and Post-installation Operation
•Under Cover Removal and Installation
•Engine Coolant Draining and Supplying (Refer to
P.14-22).
•Air Cleaner Assembly Removal and Installation (Refer to
GROUP 15 P.15-3).
•Thermostat Removal and Installation (Refer to P.14-26).
AC203411
1 234
5 67
8
10 9
13 ± 2 N·m 23 ± 4 N·m
13 ± 2 N·m
N
N
AC
111213
N
Removal steps
1. Water temperature sensor unit
connector
2. Water temperature gauge unit
connector
3. Control wiring harness and harness
bracket
<> >>B<<4. Radiator upper hose connection
5. Throttle body water feed hose
6. Thermostat case assembly7. Thermostat case gasket
>>A<<8. Cooling water line O-ring
9. Control wiring harness clamp
10. Throttle body water return hose
11. Heater water hose connection
12. Water pump inlet pipe
>>A<<13. Cooling water line O-ringRemoval steps (Continued)

WATER HOSE AND WATER PIPE
ENGINE COOLING14-32
REMOVAL SERVICE POINT
<> RADIATOR UPPER HOSE
DISCONNECTION
After making mating marks on the radiator upper
hose and hose clamp, disconnect the radiator upper
hose.
INSTALLATION SERVICE POINTS
>>A<< COOLING WATER LINE O-RING
INSTALLATION
CAUTION
Do not allow engine oil or other grease to adhere
to the O-ring
Insert the cooling water line O-ring to the water pump
inlet pipe, and coat the outer portion of the cooling
water line O-ring with water or engine coolant.
>>B<< RADIATOR UPPER HOSE
CONNECTION
1. Insert radiator upper hose as far as the projection
of the thermostat case assembly.
2. Align the mating marks on the radiator upper hose
and hose clamp, and then connect the radiator
upper hose.AC200641AC
Mating marks
AC200644
AD
Cooling water
line O-ring
Water pump inlet pipeWater pump or thermostat case
AC200642
Mating marks
Projection
Thermostat case assemblyAI
Radiator upper
hose

WATER HOSE AND WATER PIPE
ENGINE COOLING14-33
REMOVAL AND INSTALLATION <4G6>M1141003300426
Pre-removal and Post-installation Operation
•Engine Coolant Draining and Supplying (Refer to
P.14-22).
•Air Cleaner Assembly Removal and Installation (Refer to
GROUP 15 P.15-3).
•Thermostat Removal and Installation (Refer to P.14-26).
AC303471
1 23 4
56
7 8 9
9
13 ± 2 N·m
23 ± 4 N·m 13 ± 2 N·m
N
N
AB
2
Sealant: Mitsubishi Genuine Part No. MD970389 or equivalentØ3 mm
Ø3 mm
5
Removal steps
<> >>C<<1. Radiator upper hose connection
>>B<<2. Cooling water outlet hose fitting
3. Throttle body water return hose
4. Throttle body water feed hose
>>B<<5. Thermostat case assembly
6. Heater water hose connection7. Control wiring harness clamp
8. Water pump inlet pipe
>>A<<9. Cooling water line O-ringRemoval steps (Continued)