low oil pressure ISUZU TF SERIES 2004 Service Manual

6-8 ENGINE DIAGNOSIS (C24SE)
Condition Possible cause Correction
Engine overheating Level of Engine Coolant too low Replenish
Thermo switch or fan motor
defective Replace
Thermostat defective Replace
Engine Coolant pump defective Correct or replace
Radiator clogged Clean or replace
Radiator filter cap defective Replace
Level of oil in engine crankcase
too low or wrong oil in engine Change or replenish
Resistance in exhaust system
increased Clean exhaust system or replace
defective parts
Throttle Position Sensor
adjustment incorrect Adjust Wide Open Throttle switch
setting
Throttle Position Sensor circuit
open or shorted Correct or replace
Cylinder head gasket damaged Replace
Cooling Fan clutch defective Replace
Fan belt slipping Adjust tension of V-belt or replace
V-belt
Engine overcooling Thermostat defective Replace (Use a thermostat set to
open at 92
C (197.6
F))
Engine lacks compression - Refer to Hard Start
Others Tire inflation pressure abnormal Adjust to recommend pressures
Brake drag Adjust
Clutch slipping Adjust or replace
Level of oil in engine crankcase
too high Correct level of engine oil

Engine Noisy
Abnormal engine noise often consists of various
noises originating in rotating parts, sliding parts and
other moving parts of the engine. It is, therefore,
advisable to locate the source of noise systematically.

Condition Possible cause Correction
Noise from crank journals or from
crank bearings
(Faulty crank journals and crank
bearings usually make dull noise
that becomes more evident when
accelerating) Oil clearance increased due to
worn crank journals or crank
bearings Replace crank bearings and
crankshaft or regrind crankshaft
and install the over size bearing
Crankshaft out of round Replace crank bearings and
crankshaft or regrind crankshaft
and install the over size bearing
Crank bearing seized Replace crank bearings and
crankshaft or regrind crankshaft
and install the over size bearing

6-12 ENGINE DIAGNOSIS (C24SE)
Engine Oil Consumption Excessive
Condition Possible cause Correction
Oil leaking Oil pan drain plug loose Retighten or replace gasket
Oil pan setting bolds loosened Retighten
Oil pan gasket broken Replace gasket
Front cover retaining bolts loose
or gasket broken Retighten or replace gasket
Head cover retaining bolts loose
or gasket broken Retighten or replace gasket
Oil filter adapter cracked Replace
Oil filter attaching bolt loose or
rubber gasket broken Retighten or replace oil filter
Crankshaft front or rear oil seal
defective Replace oil seal
Oil pressure unit loose or broken Retighten or replace
Blow-by gas hose broken Replace hose
Engine/Transmission coupling
area Replace oil seal
Oil leaking into combustion
chambers due to poor seal in
valve system Valve stem oil seal defective Replace
Valve stem or valve guide worn Replace valve and valve guide
Oil leaking into combustion
chambers due to poor seal in
cylinder parts Cylinders and pistons worn
excessively Rebore cylinder and replace
pistons and others
Piston ring gaps incorrectly
positioned Correct
Piston rings set with wrong side
up Correct
Piston rings sticking Rebore cylinder and replace
pistons and others
Piston ring and ring groove worn Replace pistons and others
Return ports in oil rings clogged Clean piston and replace rings
Crank case ventilation, Positive
Crankcase Ventilation System
malfunctioning Positive Crankcase Ventilation
Hose clogged Clean
Others Improper oil viscosity Use oil of recommended S.A.E.
viscosity
Continuous high speed driving
and or severe usage such as
trailer towing Continuous high speed operation
and or severe usage will normally
cause increased oil consumption

ENGINE DIAGNOSIS (C24SE) 6-13
Fuel Consumption Excessive
Condition Possible cause Correction
Trouble in fuel system Mixture too rich or too lean due to
trouble in fuel injection system Refer to "Abnormal Combustion"
Fuel cut function does not act Refer to "Abnormal Combustion"
Trouble in ignition system Misfiring or abnormal combustion
due to trouble in ignition system Refer to Hard Start or Abnormal
Combustion Troubleshooting
Guide
Others Engine idle speed too high Reset Idle Air Control Valve
Returning of accelerator control
sluggish Correct
Fuel system leakage Correct or replace
Clutch slipping Correct
Brake drag Correct
Selection of transmission gear
incorrect Caution operator of incorrect gear
selection
Oil Problems
Condition Possible cause Correction
Oil pressure too low Wrong oil in use Replace with correct engine oil
Relief valve sticking Replace
Oil pump not operating properly Correct or replace
Oil pump strainer clogged Clean or replace strainer
Oil pump worn Replace
Oil pressure gauge defective Correct or replace
Crankshaft bearing or connecting
rod bearing worn Replace
Oil contamination Wrong oil in use Replace with new engine oil
Oil filter clogged Replace oil filter
Cylinder head gasket damage Replace gasket
Burned gases leaking Replace piston and piston rings or
rebore cylinders
Oil not reaching valve system Oil passage in cylinder head or
cylinder body clogged Clean or correct

Engine Oil Pressure Check
1. Check for dirt, gasoline or water in the engine
oil.
a. Check the viscosity of the oil.
b. Change the oil if the viscosity is outside the
specified standard.
c. Refer to the "Maintenance and Lubrication"
section of this manual.
2. Check the engine oil level.
The level should fall somewhere between the
"ADD" and the "FULL" marks on the oil level
dipstick.
If the oil level does not reach the "ADD" mark on
the oil level dipstick, engine oil must be added. 3. Remove the oil pressure unit.
4. Install an oil pressure gauge.
5. Start the engine and allow the engine to reach
normal operating temperature (About 80
C).
6. Measure the oil pressure.
Oil pressure should be:
150 kPa(21.8 psi) at idle speed.
7. Stop the engine.
8. Remove the oil pressure gauge
9. Install the oil pressure unit.
10. Start the engine and check for leaks.

ENGINE MECHANICAL (C24SE) 6A-11
Main Data and Specifications
Engine - General C24SE
Engine type Four-cycle, water cooled cross-flow with single over head
camshaft
Micro-computer control, fuel injection
Combustion chamber type (Volume) Hemispherical (43.3cm3)
Timing train system Belt drive
No. of cylinders-bore
stroke mm (in) 4-87.5
100.0 (3.44
3.93)
Bore Spacing(C/L to C/L) 93.0 mm (3.66 in)
Firing Order 1-3-4-2
Bore
Stroke mm (in) 87.5
100.0 (3.44
3.93)
Total piston displacement cm3 (in3) 2,405(146.80)
Combustion Chamber Volume 43.3cm3
No. of piston ring Compression ring: 2, Oil ring: 1
Compression pressure kg/cm2 (psi/pa) 12.2-16.3 (174-232/1200-1600)
Ignition timing (BTDC) No adjustment
Idling speed: rpm(WO/AC,W/AC) A/C off 825
Valve clearances (At cold)
Intake mm (in) 0 (0) (Hydraulic valve lash adjustment)
Exhaust mm (in) 0 (0) ( " )
Open at (BTDC) deg 1730’
Close at (ABDC) deg 7630’
Exhaust valves
Open at (BBDC) deg 5830’
Close at (ATDC) deg 3530’
Ignition system Fully transistorized battery ignition
Distributor type Not applicable, Electronic Spark Timing control
Distributor advance type Not applicable, Electronic Spark Timing control
Spark plug type RN9YC4
Spark plug gap mm (in) 1.0--1.1 (0.039--0.043)
Lubrication system
Lubricating method Fully flow pressure circulation
Special engine oil (API grade) SE, SF, SG or SH grade
Oil pressure kg/cm2 (psi/Pa) rpm 4-4.6 (56.9-65.4/400-450)
Oil pump type Gear
Oil filter type Cartridge full flow
Oil capacity lit. (US/UK gal.) 4.25
Cooling system
Radiator type Corrugated fin with reserve tank
Coolant capacity lit.
(US/UK gal.) 2.3 (0.66/0.55)
Water pump type Centrifugal
Thermostat Wax pellet with jiggle hole

ENGINE MECHANICAL (C24SE) 6A-13
Valve System C24SE
Actuation Type Direct-acting Inverted Bucked Tappet
Valve Clearance Adjustment Hydraulic
Valve Rotor Type None
Inlet-Valve Material Chromium Alloyed Steel
-Seat Insert Material Sintered Iron
Exhaust-Valve Material Head: Cr-Mn-Ni Alloyed Shaft: Cr-Si Alloyed &Cr plated
-Seat Insert Material Sintered Iron
Valve Spring Material GME 06 100-C1
Valve Guide Material QS 13 MR 00
Valve Seal Type Lip

Water Pump C24SE
Type Centrifugal
Drive-Material &Type HNBR Toothed-belt
Bearing Type Double Row Ball
Shaft Seal Type Mechanical Ceramic

Thermostat-Coolant C24SE
Type Bypass

Oil Pump & Filter C24SE
Type Gear Pump
Location Front of Engine
Drive Direct Crankshaft Driven
Filter Type Full Flow with Bypass for blocked filter

Oil & Oil Reservoir C24SE
Reservoir-Description & Location 1-piece below Engine
Reservoir Material Aluminum Alloy (pressure cast)
Replacement Oil Fill Volume
-With Filter change 4.25liters
-Without Filter change 4.00liters
Recommended Oil-Run-in 10W/30SG
-Service (above-18C) 10W/40SG
-Service (below-18C) 5W/30SG
Oil Classification API&CCMC

Ignition Components C24SE
Spark Plugs Conventional
Type Electronic Spark Control
No. of Coils &Type 2 Solid State
Coil Location Engine-mounted
Ignition Lead Type Inductive (hi-resistance)

ENGINE MECHANICAL (C24SE) 6A-59






Bypass Valve
Removal
1. Remove oil filter.
2. Remove bypass valve by cutting thread in locking disc
with M 10 tap (3rd stage), turning in M 10 bolt and taking
out bypass valve from seating.
Installation
1. Install bypass valve using drift (diameter approx.
15mm/0.6in.).






Oil Filter
Removal
1. Remove oil filter using commercially available tool.

Installation
1. Install oil filter by hand and oil seal ring.
2. Fill up engine oil while preventing overflow.



Oil Pump
Removal
1. Remove rear toothed belt cover, and oil pan according to
the corresponding operations.
2. Remove oil filter, wiring plug from oil pressure switch, oil
pump from cylinder block, and oil pressure switch from
oil pump.









Clean
Sealing surfaces

Installation
1. Install oil pressure switch to oil pump, oil pump to cylinder
block, oil pan, bearing bridge wiring plug, oil filter and
toothed belt cover.

Tighten (Torque)
Oil pressure switch to oil pump - 30 N

m (3.2 kgf

m)
Oil pump to cylinder block - 6 N

m (0.6 kgf

m)
Oil intake pipe to oil pump - 8 N

m (0.8 kgf

m)
Intake pipe bracket to cylinder block - 8 N

m (0.8 kgf

m)
*Insert bolts with Locktite (Refer to General Description
Recommended Liguid Gasket)

6A-76 ENGINE MECHANICAL (C24SE)
TECHNICAL DATA
SOHC Gasoline Engine C24SE

Engine Oil Viscosity
The following engine oils can be used:
A = single-grade oils
B = multigrade oils
C = easy run oils
depending on the outside temperature.

Engine Oil Quality
It is important that the following API and CCMC classes are
used:


Engines Single and multigrade oils Easy run oils
Petrol API-SF/CC, SF/CD, SG/CC,
SG/CD, CCMC/G4 API-SF/CC, SF/CD, SG/CD
CCMC-G5/PD2




Important!
CD engine oils designed by manufacturers specially for diesel
engines are not suitable for petrol engines, unless a sufficient
performance class for petrol engines (e.g. API-SF/CCMC-G4)
is also indicated.

Disposal.
Observe the relevant national regulations when disposing of
used oil.


Engine Oil Filling Quantities

Engine Model Initial filling
(litres) Filling quantity
with filter change*
(litres) MIN to MAX
(litres)
2.4L 4.80 4.25 1.00
*Up to mark "MAX" on oil dipstick




Oil Pump
Backlash 0.1 to 0.2mm
Gaps in gears opposite housing 0.03 to 0.1mm
Oil pressure at idle speed Engine at operating
temperature (>70
C oil and
approx. 80
C coolant)
450 - 500 kpa
Oil drain plug M14  1.5

ENGINE MECHANICAL (C24SE) 6A-77

Cooling System
Radiator

Type: Cross-flow

Radiator core surface in cm
2: 2000

Cooling system capacity (in litres): 7.2



Anti-freeze Mixture
Anti-freeze Mixture

Required
Quantity Up to-10




C
Quantity in litres Up to-20




C
Quantity in litres Up to-30




C
Quantity in litres Up to-40




C
Quantity of litres
(in litres) Water
(80%) Anti-
Freeze
(20%) Water
(66%) Anti-
Freeze
(34%) Water
(56%) Anti-
Freeze
(44%) Water
(48%) Anti-
Freeze
(52%)
7.2 5.7 1.5 4.7 2.5 4.0 3.2 3.4 3.8



Cooling System (continued)
Fan

Type Visco Clutch Fan
Number of blades 5
Distribution of blades asymmetric
Diameter mm



Radiator cap

Boiling point 123
C
Opening pressure kPa (bar) 120 to 135 (1.20 to 1.35)



Thermostat

Start of opening 92
C
Fully opened 107
C
Type Bypassed



Idle Speeds, CO Content, Ignition
Adjustment

Applicable System Idle speed in min-1 (rpm)
Manual CO content
in vol. % Ignition timing in CA BTDC (adjustment
ensues at able speed,
ignition marks must align) with TDC
sensor measuring instrument:
Closed Loop System 825 *<0.4 *** 8 to 12
Open Loop System 825
**1.0+0.2
-0.5 *** 8 to 12
Note) * CO content adjustment not applicable.
** CO content adjustment refer to Section 6E1 (W/O catalytic converter system)
*** Ignition timing adjustment not possible.

ENGINE MECHANICAL (C24SE) 6A-87
Recommended Torque Values
Nm (kgfm)

Bearing cover to cylinder block ....................................................................................... 60
1) 6.1 +40
to 50

Bracket for alternator to cylinder block ............................................................................ 40 4.1
Bracket for engine damping block to transmission ......................................................... 60
2) 6.1
Bracket for engine damping block to engine block ......................................................... 60 6.1
Bracket for pump/compressor to engine block ............................................................... 35 3.6
Camshaft housing cover to housing ................................................................................ 8 0.8
Camshaft timing gear to camshaft .................................................................................. 50 5.1
Clamping bracket for alternator to intake manifold ......................................................... 25 2.5
Clamping bracket to alternator ........................................................................................ 25 2.5
Con-rod bearing cap to con-rod ...................................................................................... 35
1) 3.5 +45
to 60

Crankshaft pulley bolts .................................................................................................... 20 2.0
Cylinder head to cylinder block ........................................................................................ 25
1)2) 2.5 +90
+90

+90

Engine damping block to engine bracket ........................................................................ 8.5 8.7
Engine damping block to side member ........................................................................... 52
1) 5.3
Exhaust manifold to cylinder head .................................................................................. 22 2.2

1) Use new bolts
2) Use new locking plates


Recommended Torque Values
Nm (kgfm)

Flywheel to crankshaft ..................................................................................................... 65
1) 6.6 +30
to 45

Front exhaust pipe to exhaust manifold .......................................................................... 25 2.5
Guide sleeve for pressure bearing to transmission ......................................................... 22 2.2
Intake manifold to cylinder head ...................................................................................... 22 2.2
Lower alternator bracket ................................................................................................. 25 2.5
Oil drain plug to oil pan .................................................................................................... 45 4.6
Oil intake pipe bracket to cylinder block .......................................................................... 6
2) 0.6
Oil intake pipe to oil pump ............................................................................................... 8 0.8
Oil pan to cylinder block .................................................................................................. 8
2)3) 0.8
Bearing bridge to cylinder block ...................................................................................... 8 2)3) 0.8
Oil pressure switch to oil pump ....................................................................................... 30 3.2
Pump for power steering (ribbed V-belt) to engine block ................................................ 30 3.2
Spark plugs in cylinder head ........................................................................................... 20 2.3
Starter support to cylinder block ...................................................................................... 25 2.5
Starter to cylinder block - engine side ............................................................................. 45 4.6
Starter to cylinder block - transmission side .................................................................... 75 7.6
Thermostat housing to cylinder head .............................................................................. 15 1.5
Toothed belt drive gear to crankshaft .............................................................................. 130
1) 13.3
Toothed belt front cover .................................................................................................. 4 0.4
Toothed belt rear cover ................................................................................................... 6 0.6
Toothed belt tension roller to oil pump ............................................................................ 20 2.3
(M10) ............................................................................ 45 4.6
Transmission to engine block ......................................................................................... 76 7.7
(M12) ............................................................................ 60 6.1
Water pump to cylinder block .......................................................................................... 17 1.7

1) Use new bolts
2) Use Locking Compound
3) Maximum installation time - 10 minutes

6B-6 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 coolant
(EC) level should be between the "MIN" and "MAX" lines of
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.
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 UNDER 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.
5. Fill the radiator to the base of the filler neck.
Fill the EC reserve tank to "MAX" line when the engine is
cold.
6. Block the drive wheels and firmly apply the parking brake.
Shift an automatic transmission to "P" (Park) or a manual
transmission to neutral.
7. Remove the radiator cap. Start the engine and warm it up a
t
2,500 - 3,000 rpm for about 30 minutes.
8. When the air comes out from the radiator filler neck and the
EC level has gone down, replenish with the EC. Repeat this
procedure until the EC level does not go down. Then stop
the engine and install the radiator cap. Let the engine cool
down.
9. After the engine has cooled, replenish with EC up to the
"MAX" line of the reserve tank.
10. Start the engine. With the engine running at 3,000 rpm,
make sure there is no running water sound from the heate
r
core (behind the center console).
11. If the running water sound is heard, repeat steps 8 to 10.