Page 953 of 6020
ENGINE COOLING 6B – 9
• After tightening radiator cap, warm up the engine at about
2000 rpm. Set heater adjustment to the highest temperature
position, and let the coolant circulate also into heater wate
r
system.
• Check to see the thermostat has opened through the
needle position of water thermometer, conduct a 5–minute
idling again and stop the engine.
• W hen the engine has been cooled, check filler neck fo
r
water level and replenish if required. Should extreme
shortage of coolant is found, check the cooling system and
reservoir tank hose for leakage.
• Pour coolant into the reservoir tank up to “MAX" line.
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Page 959 of 6020
ENGINE COOLING 6B – 15
RADIATOR
REMOVAL AND INSTALLATION
Radiator and Associated Parts
RTW 36BLF000101
Legend
1. Radiator Hose
2. Drain Plug
3. Fan Guide, Lower
4. Fan Guide
5. Bracket
6. Reserve Tank Hose
7. Reserve Tank
8. Radiator Cap
9. Radiator Assembly
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Page 961 of 6020

ENGINE COOLING 6B – 17
Inspection and Repair
Make the necessary adjustments, repairs, and part
replacements if excessive wear or damage is discovered
during inspection.
Radiator Cap
Measure the valve opening pressure of the pressurizing valve
with a radiator filler cap tester.
Replace the cap if the valve opening pressure is outside the
standard range.
Valve opening pressure kPa (psi) 93.3
∼
∼∼
∼122.7 (13.5
∼
∼∼
∼17.8)
Cap tester: 5–8840–0277–0
Adapter: 5–8840–2603–0
Check the condition of the vacuum valve in the center of the
valve seat side of the cap. If considerable rust or dirt is found,
or if the valve seat cannot be moved by hand, clean or replace
the cap.
110RS006
Valve opening vacuum kPa (psi) 1.96 ∼
∼∼
∼ 4.91 (0.28 ∼
∼∼
∼ 0.71)
Radiator Core
1. A bent fin may result in reduced ventilation and overheating
may occur. All bent fins must be straightened. Pay close
attention to the base of the fin when it is being straightened.
2. Remove all dust, bugs and other foreign material.
Flushing the Radiator
Thoroughly wash the inside of the radiator and the engine
coolant passages with cold water and mild detergent. Remove
all signs of scale and rust.
Cooling System Leakage Check
Use a radiator cap tester to force air into the radiator through
the filler neck at the specified pressure of 196 kPa (28.5 psi)
with a cap tester:
• Leakage from the radiator
• Leakage from the coolant pump
• Leakage from the water hoses
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Page 1524 of 6020

ENGINE COOLING (4JK1/4JJ1) 6B-1
SECTION 6B
ENGINE COOLING
TABLE OF CONTENTS
Main Data and Specifications ............................. 6B-2
General Description............................................ 6B-3 Coolant Flow ................................................... 6B-3
W ater Pump .................................................... 6B-4
Thermostat ...................................................... 6B-4
Radiator ........................................................... 6B-5
Antifreeze Solution .......................................... 6B-5
Diagnosis............................................................ 6B-6
Draining and Refilling Cooling System ............... 6B-7
W ater Pump ....................................................... 6B-8 Removal .......................................................... 6B-8
Inspection and Repair ..................................... 6B-9
Installation ....................................................... 6B-9
Thermostat ......................................................... 6B-11 Removal .......................................................... 6B-11
Inspection and Repair ..................................... 6B-11
Operating Test of Thermostat ......................... 6B-11
Installation ....................................................... 6B-12
Radiator .............................................................. 6B-13 Radiator and Associated Parts........................ 6B-13
Removal .......................................................... 6B-14
Inspection and Repair ..................................... 6B-15
Radiator Cap ................................................... 6B-15
Radiator Core .................................................. 6B-15
Flushing the Radiator ...................................... 6B-15
Cooling System Leakage Check ..................... 6B-15
Installation ....................................................... 6B-16
Engine Coolant Change .................................. 6B-16
Fan Clutch with Cooling Fan .............................. 6B-17 Inspection and Repair ..................................... 6B-17
Special Tools................................................... 6B-18
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Page 1525 of 6020

6B-2 ENGINE COOLING (4JK1/4JJ1)
Main Data and Specifications
Description Item
M/T A/T
Cooling system
W ater pump type
Pump to crankshaft speed ratio (To 1)
Delivery volume lit (US/UK gal)/min
Pump speed at 5600 rpm
W ater temperature at 30 °C (86 °F)
Pump bearing type
Thermostat type
Valve initial opening temperature °C ( °F)
Valve full opening temperature °C ( °F)
Valve lift at fully open position mm (in) Engine coolant forced circulation
Centrifugal impeller type 1.25
240 (63.1/53.3)
Double row shaft
W ax pellet with jiggle valve 85 (185)
100 (212) 10 (0.39)
Radiator Tube type corrugated
Heat radiation capacity kW (kcal/h) 93 (80.2)
Heat radiation area m2 (ft2) 11.63 (125.2)
Radiator front area m2 (ft2) 0.28 (3)
Radiator dry weight N (kg/lb) 52 53
Radiator cap valve opening pressure kPa (kg/cm2/psi) 93.3 - 122.7 (0.95 - 1.25/13.5 - 17.8)
Engine coolant capacity lit (U.S pint) 4.0 (8.5) 4.0 (8.5)
Engine coolant total capacity lit (U.S pint) 8.7 (18.4) 8.6 (18.2)
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Page 1528 of 6020
ENGINE COOLING (4JK1/4JJ1) 6B-5
Radiator
The radiator is a tube type with corrugated fins. In order
to raise the boiling point of the coolant, the radiator is
fitted with a cap in which the valve is operated at 93.3 -
122.7 kPa (0.95 - 1.25 kg / cm
2 / 13.5 - 17.8 psi)
pressure. (No oil cooler provided for M/T)
RTW 56BSH000301
Antifreeze Solution
NOTE:
Antifreeze solution + W ater = Total cooling system
capacity.
Total Cooling System Capacity Lit
(US / UK gal) (US pint)
M/T 8.7 (2.3/1.9) (18.4)
A/T 8.6 (2.3/1.9) (18.2)
See section 0B MAINTENANCE AND LUBRICATION .
F06RW 005
NOTE:
To maintain the corrosion resistance of the aluminum
radiator, water and antifreeze must be combined in a
1:1 solution (50% antifreeze and 50% water).
RTW 76BSH000201
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Page 1529 of 6020
6B-6 ENGINE COOLING (4JK1/4JJ1)
Diagnosis
Engine Cooling Trouble
Condition Possible Cause Correction
Low Engine Coolant level Replenish
Thermo meter unit faulty Replace
Faulty thermostat Replace
Faulty Engine Coolant temperature
sensor Repair or replace
Clogged radiator
Clean or replace
Faulty radiator cap Replace
Low engine oil level or use of
improper engine oil Replenish or change oil
Clogged exhaust system
Clean exhaust system or replace
faulty parts
Faulty Throttle Position sensor Replace throttle valve assembly
Open or shorted Throttle Position
sensor circuit Repair or replace
Engine overheating
Damaged cylinder head gasket Replace
Engine overcooling Faulty thermostat Replace
Faulty thermostat Replace Engine slow to warm–up
Thermo unit faulty Replace
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Page 1530 of 6020

ENGINE COOLING (4JK1/4JJ1) 6B-7
Draining and Refilling Cooling System
Before draining the cooling system, inspect the system
and perform any necessary service to ensure that it is
clean, does not leak and is in proper working order.
The engine coolant (EC) level should be between the
“MIN" and “MAX" lines of the reserve tank when the
engine is cold. If low, check for leakage and add EC up
to the “MAX" line.
There should not be any excessive deposit of rust o
r
scales around the radiator cap or radiator filler hole, and
the EC should also be free from oil.
Replace the EC if excessively dirty.
1. Remove the radiator skid plate.
2. Completely drain the cooling system by opening the drain plug at the bottom of the radiator.
RTW 56BSH000301
3. Remove the radiator cap.
WARNING:
To avoid the danger of being burned, do not
remove the cap while the engine and radiator are
still hot. Scalding fluid and steam can be blown out
under pressure.
4. Disconnect all hoses from the EC reserve tank.
Scrub and clean the inside of the reserve tank with soap and water. Flush it well with clean water,
then drain it. Install the reserve tank and hoses.
5. Refill the cooling system with the EC using a
solution that is at least 50 percent antifreeze.
Procedure for filling with coolant (in case of full change).
• Make sure that the engine is cool.
• Open radiator cap and pour coolant up to fille
r
neck.
• Pour coolant into reservoir tank up to “MAX" line.
• Tighten radiator cap and start the engine. Afte
r
idling for 2 to 3 minutes, stop the engine and
reopen the radiator cap. If the water level is lower,
replenish.
WARNING:
When the coolant is heated to a high temperature,
be sure not to loosen or remove the radiator cap.
Otherwise you might get scalded by hot vapor o
r
boiling water. To open the radiator cap, put a piece
of thick cloth on the cap and loosen the cap slowly
to reduce the pressure when the coolant has
become cooler.
• After tightening the radiator cap, warm up the
engine at about 2000 rpm. Set heater adjustment
to the highest temperature position, and let the
coolant circulate also into heater water system.
• Check to see the thermostat has opened through
the needle position of the water thermometer,
conduct a 5–minute idling again and stop the
engine.
• W hen the engine has been cooled, check fille
r
neck for water level and replenish if required.
Should extreme shortage of coolant be found,
check the cooling system and reservoir tank hose
for leakage.
• Pour coolant into the reservoir tank up to “MAX"
line.
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ISUZU KB P190 2007