2004 ISUZU TF SERIES check engine

6A – 26 ENGINE MECHANICAL



041RY00011
Draining Procedure
The indicator light will come on when the water level in the
water separator exceeds the specified level.
Drain the water and foreign material from the water
separator (inside chassis frame) with the following
procedure.





1. Place the drain pan under the drain plug.
2. Loosen the drain plug and drain water.
3. After draining the water, tighten the drain plug.
4. Operate the priming pump on the fuel filter several
times and check for fuel leakage.
5. Check the water separator indicator light. It should be
off.



Except EURO III model
RTW46ASH002901




For EURO III model
RTW46ASH000501


Air Bleeding
1. Operate the priming pump until strong resistance is
felt.
2. Wait 1 minute, and operate the priming pump until
strong resistance is felt.
3. Once more wait, and operate the priming pump until
strong resistance is felt.
4. Turn the ignition switch to the "ON" position. Wait until
the glow indicator lamp turns off.
5. Turn the ignition switch to the "START" position and
crank the engine until it starts.
6. If the engine does not start, repeat Step 3 - 5.
7. Allow the engine to idle for 3 minutes to bleed air
completely form the fuel system and check for fuel
leakage.
Note:
Insufficient air bleeding may cause the Diagnostic
Trouble Code (DTC) store or improper engine
performance.

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 – 28 ENGINE MECHANICAL


Cooling System Inspection
Install a radiator filler cap tester to the radiator. Apply
testing pressure to the cooling system to check for
leakage. The testing pressure must not exceed the
specified pressure.

Testing Pressure kPa(kg/cm
2 /psi)
150 (1.5/21)



Radiator Cap Inspection
The radiator filler cap is designed to maintain coolant
pressure in the cooling system at 103 kPa(1.05 kg/cm2,
15psi).
Check the radiator filler cap with a radiator filler cap tester.
The radiator filler cap must be replaced if it fails to hold the
specified pressure during the test procedure.
Radiator Cap Valve Opening Pressure
kPa(kg/cm
2 /psi)
90 – 120 (0.9 – 1.2/13 – 17)

Negative Valve (Reference) kPa(kg/cm2 /psi)
1.9 – 4.9 (0.02 – 0.05/0.28 – 0.71)
030LX003
030LX002

ENGINE MECHANICAL 6A – 29


Thermostat Operating Test
1. Completely submerge the thermostat in water.
2. Heat the water.
Stir the water constantly to avoid direct heat being
applied to the thermostat.
3. Check the thermostat initial opening temperature.
Thermostat Initial Opening Temperature C (F)
82 (180)
Oil Cooler Thermo Valve C (F)
76.5 (170)
EGR Cooler Thermo Valve C (F)
40 (104)

4. Check the thermostat full opening temperature.
Thermostat Full Opening Temperature C (F)
95 (203)
Oil Cooler Thermo Valve C (F)
90 (194)
EGR Cooler Thermo Valve C (F)
55 (131)
Valve Lift at Fully Open position mm (in)
9.5 (0.37)
Oil Cooler Thermo Valve mm (in)
4.5 (0.18)
EGR Cooler Thermo Valve mm in)
3.5 (0.14)



Drive Belt Adjustment
Check drive belts for wear or damage, and replace with
new ones as necessary. Check belts for tension, and
adjust as necessary.
1 Crankshaft damper pulley
2 Generator pulley
3 Cooling fan pulley
4 Oil pump pulley or idler pulley
5 Compressor pulley or idler pulley


030LX014
033RY00002

ENGINE MECHANICAL 6A – 31
VALVE CLEARANCE ADJUSTMENT
1. Bring the piston in either the No. 1 cylinder or the No. 4
cylinder to TDC on the compression stroke by turning
the crankshaft until the crankshaft damper pulley TDC
line is aligned with the timing pointer.

014RY00014











2. Check the rocker arm shaft bracket nuts for
looseness.
Tighten any loose rocker arm shaft bracket nuts
before adjusting the valve clearance.

Rocker Arm Shaft Bracket Nut Torque N·m (kg·m /lb·ft)
54 (5.5/40)


014RY00015
8. Check for play in the No. 1 intake and exhaust valve
push rods.
If the No. 1 cylinder intake and exhaust valve push
rods have play, the No. 1 piston is at TDC on the
compression stroke.
If the No. 1 cylinder intake and exhaust valve push
rods are depressed, the No. 4 piston is at TDC on the
compression stroke.

014RY00016
Adjust the No.1 or the No. 4 cylinder valve clearances
while their respective cylinders are at TDC on the
compression stroke.
Valve Clearance (At Cold) mm (in)
0.4 (0.016)

9. Loosen each valve clearance adjusting screw as
shown in the illustration.
10. Insert a feeler gauge of the appropriate thickness
between the rocker arm and the valve stem end.


014RY00017


11. Turn the valve clearance adjusting screw until a slight
drag can be felt on the feeler gauge.
12. Tighten the lock nut securely.
13. Rotate the crankshaft 360.
14. Realign the crankshaft damper pulley TDC notched
line with the timing pointer.
15. Adjust the clearances for the remaining valves as
shown in the illustration.

ENGINE MECHANICAL 6A – 33
INJECTION TIMING ADJUSTMENT
(4JA1T(L) only)
1. Check that the notched line on the injection pump
flange is aligned with the front plate or the timing gear
case notched line.





2. Bring the piston in the No. 1 cylinder to TDC on the
compression stroke by turning the crankshaft until the
crankshaft pulley TDC line is aligned with the timing
mark.
Note:
Check for play in the No. 1 intake and exhaust valve
push rods.
If the No. 1 cylinder intake and exhaust valve push
rods have play, the No. 1 piston is at TDC on the
compression stroke.
RTW46ASH000601
3. Disconnect the injection pipe from the injection pump
4. Remove one bolt from the distributor head.
5. Install the static timing gauge.
The probe of the gauge should be depressed inward
approximately 2 mm (0.079 in).
Static Timing Gauge: 5-8840-0145-0 (J-28827)

6. Rotate the crankshaft to bring the piston in the No. 1
cylinder to a point 30 - 40 BTDC.
7. Set the timing gauge needle to zero.
8. Move the crankshaft pulley slightly in both directions to
check that the gauge indication is stable.

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 – 35
Fast Idling Speed Inspection
1. Set tachometer to the engine.
2. Disconnect the vacuum hose

from the fast idle
actuator
 on the injection pump.
3. Disconnect the other vacuum hose
 from the
vacuum switching valve
 and connect it to the fast
idle actuator
.
The vacuum line will now be connected directly from
the vacuum pump
 to the fast idle actuator.
4. Check the engine fast idling speed.
If the engine idling speed is outside the specified
range, it must be adjusted.
Fast Idling Speed rpm
850  25

Fast Idling Speed Adjustment
1. Loosen the fast idle actuator bracket bolts.

2. Adjust the fast idling speed by moving the actuator
bracket, so that the clearance “S” can be 1 ~ 2 mm
(0.04 ~ 0.08 in.).
3. Tighten the bracket bolts.


Accelerator Control Cable Adjustment
Refer to Sec. 6H-6 (Accelerator Control)