2004 ISUZU TF SERIES light

6-2 ENGINE DIAGNOSIS (C24SE)
Engine Diagnosis
Hard Starting
1.Starting Motor Does Not Turn Over
Trouble Shooting Procedure
Turn on headlights and starter switch.
Condition Possible cause Correction
Headlights go out or dim
considerably Battery run down or under
charged Recharge or replace battery
Terminals poorly connected Clean battery posts and terminals
and connect properly
Starting motor coil circuit shorted Overhaul or replace
Starting motor defective Overhaul or replace
2.Ignition Trouble - Starting Motor Turns Over But Engine Does Not Start
Spark Test
Disconnect a high tension cable from any spark plug.
Connect the spark plug tester (use commercially
available tool), crank the engine, and check if a spark is
generated in the spark plug tester. Before cranking the
engine, make sure that the spark plug tester is properly
grounded. To avoid electrical shock, do not touch the
high tension cable while the engine is running.

Condition Possible cause Correction
Spark jumps across gap Spark plug defective Clean, adjust spark gap or replace
Spark plug wire in correct Connect properly or replace
Ignition timing incorrect Refer to Ignition System
Fuel not reaching fuel injector(s)
or engine Refer to item 3 (Trouble in fuel
system)
Valve timing incorrect Adjust
Engine lacks compression Refer to item 4 (Engine lacks
compression)
No sparking takes place Ignition coil disconnected or
broken Connect properly or replace
Electronic Ignition System with
module Replace
Poor connections in engine
harness Correct
Engine Control Module cable
disconnected or defective Correct or replace

ENGINE DIAGNOSIS (C24SE) 6-9
Abnormal Noise Due to Hydraulic Lash Adjuster
Should abnormal noise due to the hydraulic lash
adjuster trouble be heard immediately after the engine
is started, inspect as follows:

Condition Possible cause Correction
Abnormal noise is heard Air contaminated Bleed
HLA is spongy Check ball valve broken Repair
Safety valve in cylinder head
broken Replace
Valve clearance is not zero HLA inside stick Replace HLA assembly

Troubleshooting Procedure
Short out each spark plug in sequence using insulated
spark plug wire removers. Locate cylinder with
defective bearing by listening for abnormal noise that
stops when spark plug is shorted out.

Condition Possible cause Correction
Noise from connecting rods or
from connecting rod bearings
(Faulty connecting rods or
connecting rod bearings usually
make an abnormal noise slightly
higher than the crank bearing
noise, which becomes more
evident when engine is
accelerated) Bearing or crankshaft pin worn Replace connecting rod bearings
and crankshaft or regrind
crankshaft and install the under
size bearing
Crankpin out of round Replace connecting rod bearings
and crankshaft or regrind
crankshaft and install the under
size bearing
Connecting rod bent Correct or replace
Connecting rod bearing seized Replace connecting rod bearings
and crankshaft or regrind
crankshaft and install the under
size bearing

Troubleshooting Procedure
Abnormal noise stops when the spark plug on the
cylinder with defective parts is shorted out.

Condition Possible cause Correction
Piston and cylinder
(Faulty piston or cylinder usually
makes a combined mechanical
thumping noise which increases
when engine is suddenly
accelerated but diminishes
gradually as the engine warms up) Piston clearance increased due to
cylinder wear Replace piston and cylinder body
Piston seized Replace piston and cylinder body
Piston ring broken Replace piston and cylinder body
Piston defective Replace pistons and others

6A-18 ENGINE MECHANICAL (C24SE)
OPERATIONS ON ENGINE AGGREGATES
Engine Damping Blocks (Engine Without
Transmission)
Removal
1. Remove bonnet.
2. Remove radiator.
3. Remove air inlet hose.
4. Remove power steering pump drive belt and power
steering pump from engine.


5. Remove all cable connections, hoses and lines from
engine.
6. Remove accelerator cable from inlet pipe.


7. Remove exhaust pipe from manifold.



8. Remove lower nine bolts and transmission from engine
block.
9. Remove clutch slave cylinder and allow to hang free.
10. Remove starter from engine block.

11. Remove upper bolts of left and right engine mounting
from damping blocks.
12. Raise engine slightly.
13. Remove lower bolts of left and right damping blocks.
14. Remove damping blocks.

ENGINE MECHANICAL (C24SE) 6A-27



Seal Ring, Camshaft Housing, Timing Side
Removal
1. Remove front toothed belt cover toothed belt from
camshaft timing gear according to the corresponding
operation.
2. Remove camshaft housing cover and camshaft timing
gear.
3. Remove sealing ring by making hole in middle of ring,
turning in self-tapping screw and edging out.


Installation
1. Install sealing ring by using 5-8840-0451-0 with camshaft
sprocket bolt and washer.
2. Install coat seal lips of shaft seal ring slightly.



Seal Ring, Thermostat Housing, Cylinder Head
Removal
1. Open radiator drain tap and collect coolant.
2. Remove toothed belt rear cover and toothed belt
according to the corresponding operation.
3. Remove camshaft housing cover.
4. Remove camshaft timing gear by counterholding
camshaft with a flat spanner.
5. Remove cable from temperature sensor.






6. Remove upper inner hex bolts of rear toothed belt cover.
7. Turn rear toothed belt cover to one side.
8. Remove thermostat housing.
9. Remove sealing ring from cylinder head.

Clean
Sealing surfaces in cylinder head and thermostat housing.

Installation
1. Install sealing ring in recess of cylinder head.

6A-28 ENGINE MECHANICAL (C24SE)


2. Install cable to temperature sensor.
3. Install upper bolts of rear toothed belt rear cover.
4. Install camshaft timing gear then check timing according
to the corresponding operation.
5. Install camshaft housing cover.
6. Install toothed belt and front cover.
7. Fill up and bleed cooling system according to the
corresponding operation.


Tighten (Torque)
Thermostat housing to cylinder head - 15 N
m/1.5 kgf
m.




Seal Ring - Front Camshaft Housing, Replace
Removal
Mark running direction of toothed belt.
Remove toothed belt-see operation “Toothed Belt, Replace”.

Camshaft housing cover, camshaft pulley-counterhold on hex
of camshaft.


Removal
Screw self-tapping screw into seal ring.

Edge out seal ring.

Installation
Lightly coat sealing lip of seal ring with protective grease.

Install seal ring with 5-8840-0451-0 into camshaft housing-use
screw and washer of camshaft pulley.

ENGINE MECHANICAL (C24SE) 6A-43


Inspection
Sealing surfaces for plane surface, guides, sliding and bearing
points for wear-see operation “Cylinder Head. Overhaul”.



Installation
1. Coat the valves with engine oil and insert in cylinder
head.
2. Install the valve spacer ring or valve rotator(exhaust) and
valve spring seal(intake).
3. Push the accompanying assembly sleeve onto valve
stem and coat with engine oil.
4. Insert a new valve stem seal with 5-8840-2601-0 (1).
5. Drive the valve stem seal carefully in to stop with light
hammer blow.







Installation
1. Install the valve springs and valve spring caps.
2. Install the tension valve springs with 5-8840-2594-0 (1),
valve keeper.

Important!
Note markings made on valves.




Tighten (Torque)
Exhaust manifold and intake manifold with new gaskets to
cylinder head.

Thermostat housing with new seal ring to cylinder head:





Tighten (Torque)
Spark plugs with spark plug wrench to cylinder head.

Installation
1. Coat hydraulic valves lifters (1) with oil.
2. Insert them in cylinder head.
Note installation position.

6A-50 ENGINE MECHANICAL (C24SE)

Clean
Sealing surfaces.



013RW004









Installation
1. Apply a bead of Sealing Compound, TB120TC or eguivalent to joint of oil pump.
2. Apply the recommended light gasket to the oil pan fitting surface as shown in the illustration.
3. Install the bearing bridge.
4. Install baffle plate, or reuse baffle plate.

Caution
Baffle plates can be retrofitted without difficulty - replace baffle
plate.

5. Install oil intake pipe to oil pump and oil intake pipe bracket to cylinder block.
6. Install oil pan and new gasket to cylinder block and insert bolts with Locking Compound 15 10 177 (90 167 347).
Maximum assembly time including torque check is 10
min.
7. Return the power steering unit (and front axle [4 
4 model
only]).
8. Install the crossmember.

Tighten (Torque)
Oil intake pipe to oil pump -8N

m (0.8 kgf

m)
Oil intake pipe bracket to cylinder block - 6 N

m (0.6 kgf

m)
Oil pan to cylinder block - 8 N

m (0.8 kgf

m)
Bearing bridge to cylinder block – 8 N

m (0.8 kgf

m)

ENGINE MECHANICAL (C24SE) 6A-51
OPERATIONS ON CRANK DRIVE
Con-Rod Bearing








Removal
1. Remove oil pan and bearing bridge according to the corresponding operation.
2. Remove con-rod bearing cap and con-rod bearing after marking both sides.

Clean
Con-rod journal, con-rod bearing cap










Installation
1. Install new bearing shafts lightly coated with engine oil.
2. Install con-rod bearing cap.

Torque-Angle Method
Con-rod bearing cap to con-rod - 35N

m (3.5 kgf

m) +45 
to
60 


Important!
Use new bolts.

3. Install oil pan and bearing bridge according to the corresponding operation.



Piston with Con-Rod
Removal
1. Remove cylinder head and oil pan according to the corresponding operations.
2. Remove piston with con-rod after marking con-rod bearing cap.





Inspection
Remove and install all parts, if applicable.

Important!
Ring gap offset:
Piston rings - 180 
.
Oil scraper rings - 25 to 50 mm/1 to 2 in. from gap of
intermediate ring to the left and to the right.