compression ratio ISUZU TROOPER 1998 Service Owner's Manual

6A – 2 ENGINE MECHANICAL
GENERAL DESCRIPTION
Cylinder Head Gasket
The cylinder head gasket is laminated steel sheets.
Three grades of the gasket according to the measured
piston head projection from the cylinder block are
provided to give the engine a minimum compression
ratio fluctuation.
Tightening Method for
Special Bolt
The cylinder head fixing bolts, flywheel bolts and
connecting rod cap fixing bolts are tightened by the
angular Tightening Method.
Piston
Auto-thermatic pistons having steel struts with a 0.4
mm offset from the piston pin center line, are applied to
reduce thermal expansion and resulting engine noise
when the engine is cold.
Bearings
The crankshaft bearings and connecting rod bearings
are of aluminum having a high bearing surface.
These bearings are especially sensitive to foreign
material such as metal scraps. So, it is very important
that the oil ports and other related surfaces are kept
clean and free of foreign material.
Crankshaft bearings are selected for optimum bearing
and journal clearance which reduces vebration and
noise.
For General Export
For Europe
F06R200004

ENGINE MECHANICAL 6A – 3
SERVICE INFORMATION
MAIN DATA AND SPECIFICATION
Engine type Diesel, four cycle water cooled inline
Camshaft type DOHC
Number of cylinders 4
Bore x stroke (mm) 95.4 x 104.9
Total piston displacement (cc) 2999
Compression ratio (to 1) 19.0
For Europe : 18.5
Engine weight (dry) N (kg/lb) 2492 (254/560) (A/T)
For Europe : 2422 (247/545) (A/T)
2649 (270/593) (M/T)
For Europe : 2697 (275/606) (M/T)
Engine idling speed (Reference) RPM 720
Compression pressure kpa (kg/cm
2/psi)-rpm 3040 (31/441)-200
Firing order 1–3–4–2
VALVE SYSTEM
Intake valves open at: B.T.D.C. 3°
close at: A.B.D.C. 57.6°
Exhaust valves open at: B.B.D.C. 56.5°
close at: A.T.D.C. 5°
Valve clearance (at cold) mm (in)
intake: 0.15 (0.006)
exhaust: 0.25 (0.01)
Oil filter Full flow and bypass combined type
Oil capacity (Original factory fill or rebuilt engine) 9.0 liters (7.9 US quarts)
Oil capacity (Service change)
with filter change 6.0 liters (6.3 US quarts)
without filter change 5.0 liters (5.3 US quarts)
Oil cooler Water cooled type
Inter cooler Air cooled type
Turbocharger method
Control method Wastegate control
Lubrication Pressurized control
Cooling method Coolant cooled
Crankshaft
As tufftriding (Nitrizing treatment) is applied to increase
crankshaft strength, crankpins and journals should not
be reground.
Piston Cooling
An oiling jet device for piston cooling is provided in the
lubricating oil circuit from the cylinder block oil gallery
via a check valve.
Take care not to damage any oiling jet when removing
and installing piston and connecting assembly.
Fuel Injection System
The injection system is oil rail type.
Quick On Start 4 System
QOS4 preheating system which features a quick-on
glow plug with thermometer control of the glowing time
and the afterglow time function, is applied.

6A – 26 ENGINE MECHANICAL
Illustration Tool No. Tool Name
SPECIAL TOOLS
5-8840-2590-0 Valve Clearance Adjusting Tool
5-8840-2592-0 Camshaft Stopper
5-8840-2591-0 Camshaft Gear Tool
5-8840-2675-0
5-8531-7002-0Compression Gauge
Adapter: Compression Gauge
5-8840-2153-0 Seal Cutter
LHDN 
   
F06RW056
F06RV037
901LX057
901LX056 F06RW057
901RT042

ENGINE MECHANICAL 6A – 67
VALVE CLEARANCE ADJUSTMENT
NOTE:
1. Valve clearance should be inspected and adjusted
while the engine is cool.
2. The tightening of the camshaft bearing cap and
camshaft carrier assembly should be checked
before inspecting and adjusting valve clearance.
INSPECTION
1. Remove cylinder head noise insulator cover and
cylinder head cover.
Refer to “Cylinder Head” in this manual.
2. Disconnect all harness connecters of the injector
and remove harness assembly.
3. Drain oil from oil rail assembly.
4. Remove injector clamp nuts and fixing bolts to take
out injector assembly.
5. Loosen oil rail bolts, remove oil rail assembly.
6. Set cylinder No.1 to the TDC at the compression
stroke. Make sure that there is play in cylinder No.1
tappets on inlet and exhaust sides and that there is
no play in cylinder No.4 tappets.
7. Measure valve clearance at No.1 TDC (Refer to the
black circles indicated in the illustration).
Standard Valve clearance:
Intake valve: 0.15 mm (0.0059 in) ± 0.05 mm (0.0020 in)
Exhaust valve: 0.25 mm (0.0098 in) ± 0.05 mm (0.0020 in)
8. Turn the crankshaft one turn to set No.4 cylinder
TDC at the compression stroke.
9. Measure valve clearance at No.4 TDC (Refer to the
black circles indicated in the illustration).
Standard Valve clearance:
Intake valve: 0.15 mm (0.0059 in) ± 0.05 mm (0.0020 in)
Exhaust valve: 0.25 mm (0.0098 in) ± 0.05 mm (0.0020 in)
10. If measured value is outside standard value,
readjust the valve clearance.
ADJUSTMENT
For valve clearance adjustment, follow the procedure
given below.
1. Set cylinder No.1 or No.4 to the TDC at the
compression stroke.
Set the valve clearance adjusting tool on the tappet
requiring adjustment.
After making sure of the correct setting of the
special tool, depress the tappet by turning the bolt.
Valve Clearance Adjusting Tool: 5-8840-2590-0
NOTE: Before depressing the tappet, set the tappet
notch in the direction where adjuster can be easily
taken out.
2. Take out the adjuster using a small screw driver and
finger magnet.
No.1
FtNo.2No.1 TDC
No.3 No.4EXH
IN
011RW045
No.1
FtNo.2No.4 TDC
No.3 No.4EXH
IN
011RW046
014RW150

6A– 90 ENGINE MECHANICAL
5. Piston Ring
1) Install the piston rings with the piston ring
expander.
The compression ring must be set with the 1N,
2N mark facing up.
2) Discerning mark is stamped as shown in the
illustration (1).
Marked 1N: 1st compression ring
Marked 2N: 2nd compression ring
3) Install piston rings in the following sequence.
1) Oil ring
(1) After installing the expander ring then assemble
the oil ring.
2) 2nd compression ring3) 1st compression ring
1) The compression ring must be set with the 1N or
2N mark facing up.
2) 1st compression ring:1N
3) 2nd compression ring: 2N
4) After installation, apply engine oil to the entire
circumference of the piston rings.
Check to see that all the rings rotate smoothly.
5) Insert the bearings into the connecting rods and
caps.
Apply new engine oil to the bearing faces.
Cap side bearings have no oil hole.
Connecting rod side bearing’s oil hole should be
aligned with oil hole on the connecting rod.
6. Piston and Connecting Rod
1) Apply engine oil to the cylinder bores, the
connecting rod bearings and the crankshaft
pins.
2) Check to see that the piston ring end gaps are
correctly positioned.
N
012RW037
2
3
1
015RW051
3
2
11
012RW058

6E±185 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Poor Fuel Economy Symptom

StepActionValue(s)Ye sNo
1DEFINITION:
Fuel economy, as measured by an actual road test, is
noticeably lower than expected. Also, economy is
noticeably lower than it was on this vehicle at one time,
as previously shown by an actual road test. (Larger than
standard tires will cause odometer readings to be
incorrect, and that may cause fuel economy to appear
poor when it is actually normal.)
Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
ÐVerify repairGo to Step 3
3Was a visual/physical check performed?
ÐGo to Step 4
Go to Visual/
Physical
Check
4Check owner's driving habits.

Is the A/C ªONº full time (defroster mode ªONº)?

Are tires at the correct pressure?

Are excessively heavy loads being carried?

Is acceleration too much, too often?

Is engine oil correct?
Was a problem found?
ÐGo to Step 5Go to Step 6
5Review the items in Step 4 with the customer and
advise as necessary.
Is the action complete?
ÐSystem OKÐ
61. Visually/physically check: Vacuum hoses for splits,
kinks, and improper connections and routing as
shown on the ªVehicle Emission Control
Informationº label.
2. If a problem is found, repair as necessary.
Was a repair required?
ÐVerify repairGo to Step 7
71. Remove and check the air filter element for dirt or for
restrictions. Refer to
Air Intake System.
2. Replace the air filter element if necessary.
Was a repair required?
ÐVerify repairGo to Step 8
81. Check for low engine coolant level. Refer to Engine
Cooling
.
2. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 9
91. Check for an incorrect or faulty engine thermostat.
Refer to
Engine Cooling.
2. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 10
101. Check for low engine compression. Refer to Engine
Mechanical
.
2. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 11