Page 578 of 687

Downloaded from www.Manualslib.com manuals search engine ENGINE COOLING 6B-1
6B
SECTION 6B
ENGINE COOLING
CONTENTS
General Description ........................................6B-2
Cooling System Circulation ........................... 6B-2
Radiator Cap ................................................. 6B-3
Coolant Reservoir ......................................... 6B-3
Water Pump .................................................. 6B-4
Thermostat .................................................... 6B-4
Cooling Fan Clutch ........................................ 6B-4
Coolant (Water) Temperature Gauge............ 6B-4
Diagnosis .........................................................6B-5
Maintenance ....................................................6B-6
Coolant .......................................................... 6B-6
Coolant Level ................................................ 6B-7
Cooling System Service ................................ 6B-7Cooling System Flush and Refill ................... 6B-8
Water Pump Belt Tension ............................. 6B-9
On-Vehicle Service ....................................... 6B-10
Cooling System Component ....................... 6B-10
Coolant Draining ......................................... 6B-11
Cooling Water Pipes or Hoses .................... 6B-11
Thermostat .................................................. 6B-11
Water Pump Belt and Cooling Fan ............. 6B-13
Radiator ...................................................... 6B-14
Water Pump ................................................ 6B-15
Required Service Material ............................ 6B-17
Tightening Torque Specification ................. 6B-17
Page 579 of 687
Downloaded from www.Manualslib.com manuals search engine 6B-2 ENGINE COOLING
General Description
The cooling system consists of the radiator cap, radiator, reservoir, hoses, water pump, cooling fan & clutch,
thermostat. The radiator is of tube-and-fin type.
Cooling System Circulation
1. Radiator inlet hose 5. Water pump 9. Heater outlet hose
2. Radiator outlet hose 6. Fast idle control plunger of throttle body 10. Radiator
3. Water inlet pipe 7. Cylinder block/cylinder head
4. Thermostat 8. Heater inlet hose
Page 581 of 687

Downloaded from www.Manualslib.com manuals search engine 6B-4 ENGINE COOLING
Water Pump
The centrifugal type water pump is used in the cooling system.
The pump impeller is supported by a totally sealed bearing.
The water pump can not be disassembled.
Thermostat
A wax pellet type thermostat is used in the cooling system.
The temperature at which the valve begins to open is stamped on
thermostat.
In the top portion of the thermostat, an air bleed valve (1) is pro-
vided; this valve is for venting out the gas or air, if any, that is
accumulated in the circuit.
Cooling Fan Clutch
Fluid is enclosed in the cooling fan clutch (2) and at its center
front, there is a bimetal (3) whose thermal reaction and the engine
speed control the cooling fan speed.
Coolant (Water) Temperature Gauge
A water temp. gauge is located at intake manifold.
This gauge activates a temp. meter in the instrument cluster.
When installing, wind sealing tape on gauge thread and tighten it.
NOTE:
Do not disassemble clutch assembly.
WARNING:
Keep hands, tools, and clothing away from engine cool-
ing fan (1) to help prevent personal injury.
Page 582 of 687
Downloaded from www.Manualslib.com manuals search engine ENGINE COOLING 6B-5
Diagnosis
Condition Possible Cause Correction
Engine overheats
Loose or broken water pump belt
Not enough coolant
Faulty thermostat
Faulty water pump
Dirty or bent radiator fins
Coolant leakage on cooling system
Defective cooling fan clutch
Plugged radiator
Faulty radiator cap
Maladjusted ignition timing
Dragging brakes
Slipping clutchAdjust or replace.
Check coolant level and add as
necessary.
Replace.
Replace.
Clean or remedy.
Repair.
Check and replace as necessary.
Check and replace radiator as
necessary.
Replace.
Check system related parts.
Adjust brake.
Adjust or replace.
Page 583 of 687

Downloaded from www.Manualslib.com manuals search engine 6B-6 ENGINE COOLING
Maintenance
Coolant
The coolant recovery system is standard. The coolant in the radiator expands with heat, and the overflow is col-
lected in the reservoir.
When the system cools down, the coolant is drawn back into the radiator.
The cooling system has been filled at the factory with a quality coolant that is either 50/50 mixture of water and
anti-freeze / anti-corrosion coolant (ethylene glycol antifreeze).
The 50/50 mixture coolant solution provides freezing protection to – 36 °C ( – 33 °F).
Maintain cooling system freeze protection at – 36 °C ( – 33 °F) to ensure protection against corrosion and
loss of coolant from boiling.
This should be done even if freezing temperatures are not expected.
Add ethylene glycol base coolant when coolant has to be added because of coolant loss or to provide added
protection against freezing at temperature lower than – 36 °C ( – 33 °F).
Anti-freeze proportioning table
Coolant capacity Freezing temperature°C– 16– 36
°F3– 33
Anti-freeze / Anti-corrosion
coolant concentration%30 50
Ratio of compound
to cooling waterItr. 1.35/3.15 2.25/2.25
US pt. 2.85/6.65 4.75/4.75
Imp pt. 2.37/5.53 3.95/3.95
Engine radiator and heater 5.2 liters (11.0/9.2 US/lmp. pt.)
Reservoir 0.7 liters (1.5/1.2 US/lmp. pt.)
Total 5.9 liters (12.5/10.5 US/lmp. pt.)
NOTE:
Alcohol or methanol base coolant or plain water alone should not be used in cooling system at any
time as damage to cooling system could occur.
Even in a market where no freezing temperature is anticipated, mixture of 70% water and 30% ethyl-
ene glycol antifreeze (Antifreeze / Anticorrosion coolant) should be used for the purpose of corro-
sion protection and lubrication.
Page 584 of 687

Downloaded from www.Manualslib.com manuals search engine ENGINE COOLING 6B-7
Coolant Level
To check level, look at “see-through” reservoir.
It is not necessary to remove radiator cap to check coolant level.
When engine is cool, check coolant level in reservoir (1).
A normal coolant level should be between “FULL” (2) and “LOW”
(3) marks on reservoir (1).
If coolant level is below “LOW” mark, remove reservoir cap and
add proper coolant to reservoir to bring coolant level up to “FULL”
mark. Then, reinstall cap.
Cooling System Service
Cooling system should be serviced as follows.
1) Check cooling system for leakage or damage.
2) Wash radiator cap and filler neck with clean water by remov-
ing radiator cap when engine is cold.
3) Check coolant for proper level and freeze protection.
4) Using a pressure tester, check system and radiator cap for
proper pressure holding capacity 1.1 kg/cm
2 (15.6 psi, 110
kPa). If replacement of cap is required, use proper cap spec-
ified for this vehicle. WARNING:
To help avoid danger of being burned:
Do not remove reservoir cap while coolant is “boiling”,
and
Do not remove radiator cap while engine and radiator
are still hot.
Scalding fluid and steam can be blown out under pres-
sure if either cap is taken off too soon.
NOTE:
If proper quality antifreeze is used, there is no need to
add extra inhibitors or additives that claim to improve
system. They may be harmful to proper operation of
system.
When installing reservoir cap, set arrow marks (4) on
the reservoir and cap as the figure.
WARNING:
To help avoid danger of being burned, do not remove
radiator cap while engine and radiator are still hot.
Scalding fluid and steam can be blown out under pres-
sure if cap is taken off too soon.
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Downloaded from www.Manualslib.com manuals search engine 6B-8 ENGINE COOLING
5) Tighten hose clamps and inspect all hoses.
Replace hoses whenever cracked, swollen or otherwise
deteriorated.
6) Clean frontal area of radiator core.
Cooling System Flush and Refill
1) Remove radiator cap when engine is cool:
Turn cap slowly to the left until it reaches a “stop” (Do not
press down while turning it).
Wait until pressure is relieved (indicated by a hissing sound)
then press down on cap and continue to turn it to the left.
2) With radiator cap removed, run engine until upper radiator
hose is hot (this shows that thermostat is open and coolant is
flowing through system).
3) Stop engine and open radiator drain plug (1) to drain cool-
ant.
4) Close drain plug. Add water until system is filled and run
engine until upper radiator hose is hot again.
5) Repeat steps 3 and 4 several times until drained liquid is
nearly colorless.
6) Drain system and then close radiator drain plug tightly.
7) Disconnect hose from water reservoir (1). Remove reservoir
and pour out any fluid. Scrub and clean inside of reservoir
with soap and water. Flush it well with clean water and drain.
Reinstall reservoir and hose.
8) Add 50/50 mixture of good quality ethylene glycol antifreeze
and water to radiator and reservoir.
Fill radiator to the base of radiator filler neck and reservoir to
“FULL” level mark (2). Reinstall reservoir cap setting the
arrow marks (4) on the reservoir and cap as the figure. NOTE:
After installing radiator cap (1) to radiator, make sure that
its ear (2) is aligned with reservoir hose (3) as shown in
figure.
If not, turn cap more to align its ear with hose.
WARNING:
To help avoid danger of being burned, do not remove
radiator cap while engine and radiator are still hot. Scald-
ing fluid and steam can be blown out under pressure if
cap is taken off too soon.
3. LOW level mark
Page 586 of 687

Downloaded from www.Manualslib.com manuals search engine ENGINE COOLING 6B-9
9) Run engine, with radiator cap removed, until radiator upper
hose is hot.
10) With engine idling, add coolant to radiator until level reaches
the bottom of filler neck. Install radiator cap, making sure
that the ear of cap lines up with reservoir hose.
Water Pump Belt Tension
1) Inspect belt for cracks, cuts, deformation, wear and cleanli-
ness. If it is necessary to replace belt, refer to “Water Pump
Belt and Cooling Fan” in this section.
2) Check belt for tension. Belt is in proper tension when it
deflects 4.5 to 5.5 mm (0.18 – 0.22 in.) under thumb pres-
sure (about 10 kg or 22 lb.).
Water pump belt tension
“a” : 4.5 – 5.5 mm (0.18 – 0.22 in.) as deflection / 10 kg (22
lbs)
3) If belt is too tight or too loose, adjust it to proper tension by
displacing generator position.
4) Tighten generator adjusting bolt and pivot bolts as specified
torque.
Tightening torque
Generator adjusting bolt (a) : 23 N·m (2.3 kg-m, 17.0 lb-ft)
Generator pivot bolts (b) : 50 N·m (5.0 kg-m, 36.0 lb-ft)
5) Connect negative cable at battery terminal.WARNING:
Disconnect negative cable at battery before checking and
adjusting belt tension.
NOTE:
When replacing belt with a new one, adjust belt tension
to 3 – 4 mm (0.12 – 0.16 in.).