ENGINE MECHANICAL 6A – 27
111R300001
COOLING SYSTEM
Coolant Level
Check the coolant level and replenish the radiator reserve
tank as necessary.
If the coolant level falls below the “MIN” line, carefully
check the cooling system for leakage. Then add enough
coolant to bring the level up to the “MAX” line.
Engine coolant Filling up procedure
1. Make sure that the engine is cool.
Warning:
When the coolant is heated to a high temperature, be
sure not to loosen or remove the rediator cap.
Otherwise you might get scalded by hot vapor or
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.
2. Open rediator cap pour coolant up to filler neck
3. Pour coolant into reservoir tank up to “MAX” line
4. Tighten radiator cap and start the engine. After idling
for 2 to 3 minutes, stop the engine and reopen radiator
cap. If the water level is lower, replenish.
5. After replenish the coolant tighten 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.
6. Check to see the thermometer, continuously idling 5
minutes and stop the engine.
7. When the engine has been cooled, check filler neck
for water level and replenish if required. Should
extreme shortage of coolant is found, check the
coolant system and reservoir tank hose for leakage.
8. Pour coolant into the reservoir tank up to “MAX” line.
Engine Coolant Total Capacity Lit (U.S / UK gal)
4JA1 / TC 9.4 (2.5 / 2.1)
4JH1TC M/T: 10.1 (2.7 / 2.2)
A/T: 10.0 (2.6 / 2.2)
Mixing Ratio (Anti-Freeze Solution/Water)
50 %
6A – 32 ENGINE MECHANICAL
COMPRESSION PRESSURE
MEASUREMENT
1. Start the engine and allow it to idle until the coolant
temperature reaches 70 – 80 C (158 – 176 F).
2. Remove the following parts.
Leak off pipe
Injection nozzle holder bracket
Injection nozzle holder
3. Install the following parts.
Set the adapter and compression gauge (SST) to
the No.1 cylinder injection nozzle hole.
Injection nozzle holder bracket
Injection nozzle holder bracket Bolt Torque
N·m (kg·m /lb·ft)
37 (3.8/27)
Compression Gauge: 5-8840-2675-0
Adapter; Compression Gauge: 5-8531-7001-0
4. Turn the engine over with the starter motor and take
the compression gauge reading.
Compression Pressure MPa (kg/cm
2 /psi) at 200 rpm
Standard Limit
3.0 (31.0/441) 2.1 (21.7/309)
5. Repeat the procedure (Steps 3 and 4) for the
remaining cylinders.
If the measured value is less than the specified limit,
refer to “Troubleshooting” in this Manual.
F06XL056
901R100003
6A – 34 ENGINE MECHANICAL
RTW46ASH000701
9. Turn the crankshaft clockwise and read the gauge
indication when the crankshaft pulley timing mark (8)
is aligned with the pointer.
Injection Timing : BTDC 8 2
Standard Reading mm (in)
0.5 (0.02)
If the injection timing is outside the specified range,
continue with the following steps.
10. Loosen the injection pump fixing nuts and bracket
bolts.
11. Adjust the injection pump setting angle.
When large than standard
value When smaller than standard
value
R A
A: Move the injection pump toward the engine.
R: Move the injection pump away from the engine.
ENGINE CONTROL (4JA1T(L) only)
Idling Speed Adjustment
1. Set the vehicle parking brake and chock the drive
wheels.
2. Place the transmission in neutral.
3. Start the engine and allow it to idle until the coolant
temperature reaches 70 - 80C (158 - 176F).
4. Disconnect the engine control cable from the control
lever.
5. Set a tachometer to the engine.
6. Check the engine idling speed.
If the engine idling speed is outside the specified
range, it must be adjusted.
Engine Idling Speed : 730 25 rpm
Idling Speed Adjustment
1. Loosen the idling set screw lock nut on the injection
pump idling set bolt.
2. Adjust the idling speed to the specified range by
turning the idling set bolt
.
3. Lock the engine set nut
with the idling set bolt lock
nut.
4. Check that the idling control cable is tight (free of
slack). If required, remove the slack from the cable.
ENGINE MECHANICAL 6A – 41
Coolant Replenishment
Warning:
When the coolant is heated to a high temperature, be
sure not to loosen or remove the rediator cap.
Otherwise you might get scalded by hot vapor or
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.
1. Open rediator cap pour coolant up to filler neck
2. Pour coolant into reservoir tank up to "MAX" line
3. Tighten radiator cap and start the engine. After idling
for 2 to 3 minutes, stop the engine and reopen radiator
cap. If the water level is lower, replenish.
4. After replenish the coolant tighten 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.
5. Check to see the thermometer, continuously idling 5
minutes and stop the engine.
6. When the engine has been cooled, check filler neck for
water level and replenish if required. Should extreme
shortage of coolant is found, check the coolant system
and reservoir tank hose for leakage.
7. Pour coolant into the reservoir tank up to "MAX" line.
Coolant Capacity lit (US/UK gal)
4JA1 / TC 9.4 (2.5 / 2.1)
4JH1TC M/T: 10.1 (2.7 / 2.2)
A/T: 10.0 (2.6 / 2.2)
9.5 (2.5/2.1)
Engine Warm-Up
After completing the required maintenance procedures,
start the engine and allow it to idle until it is warm.
Check the following:
1. Engine idling speed.
2. Engine noise level.
3. Engine lubricating system and cooling system.
Carefully check for oil and coolant leakage.
4. Clutch engagement.
5. Transmission operation.
6. Indicator warning light operation.
ENGINE COOLING 6B – 3
MAIN DATA AND SPECIFICATIONS
Description Item
M/T A/T
Cooling system
Water pump type
Pump to crankshaft speed ratio (To 1)
Delivery volume lit (US/UK gal)/min
Pump speed at 3000 rpm
Water temperature at 30C (86F)
Pump bearing type
Thermostat type
Valve initial opening temperature C (F)
(Oil cooler thermo valve)
(EGR cooler thermo valve)
Valve full opening temperature C (F)
(Oil cooler thermo valve)
(EGR cooler thermo valve)
Valve lift at fully open position mm (in)
(Oil cooler thermo valve)
(EGR cooler thermo valve) Engine coolant forced circulation
Centrifugal impeller type
1.2
100 (26.3/22.2)
Double row shaft
Wax pellet with jiggle valve
82 (180)
76.5 (170)
40 (104)
95 (203)
90 (194)
55 (131)
9.5 (0.37)
4.5 (0.18)
3.5 (0.14)
Radiator Tube type corrugated
Heat radiation capacity 93.0 kw (79,980 kcal/h)
Heat radiation area
11.63 m (1.081ft)
Radiator front area
0.28m (0.026 ft)
Radiator dry weight 52 N (5.3 kg/11.7 lb) 53 N (5.4 kg/11.9 lb)
Radiator cap valve opening pressure
93.3 122.7kpa (13.5 17.8psi)
Engine coolant capacity 2.4 lit (5.1 U.S pint) 2.3 lit (4.9 U.S pint)
Engine coolant total capacity 10.1 lit (21.3 U.S pint) 10.0 lit (21.1 U.S pint)
6B – 4 ENGINE COOLING
GENERAL DESCRIPTION
COOLANT FLOW
RTW46ALF001101
The engine cooling system consists of the radiator, the water pump, the cooling fan, and the thermostat.
To quickly increase cold engine coolant temperature for smooth engine operation, the coolant is circulated by the
water pump and thermostat through the bypass hose and back to the cylinder body.
The coolant does not circulate through the radiator.
When the coolant temperature reaches specified value, the thermostat will begin to open and a gradually increasing
amount of coolant will circulate through the radiator.
The thermostat will be fully open when the coolant temperature reaches specified value. All of the coolant is now
circulating through the radiator for effective engine cooling.
ENGINE COOLING 6B – 7
DIAGNOSIS
Engine Cooling Trouble
Symptom Possible Cause Action
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
6B – 8 ENGINE COOLING
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 coolan
t
(EC) level should be between the “MIN" and “MAX" lines o
f
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 or scales
around the radiator cap or radiator filler hole, and the EC
should also be free from oil.
Replace the EC if excessively dirty.
P1010064
1. Completely drain the cooling system by opening the drain
plug at the bottom of the radiator.
2. 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 unde
r
pressure.
3. 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.
4. 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 pour coolant up to filler neck.
Pour coolant into reservoir tank up to “MAX" line.
Tighten radiator cap and start the engine. After idling for 2
to 3 minutes, stop the engine and reopen 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 radiato
r
cap. Otherwise you might get scalded by not vapor or
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.