Mitsubishi 4G6 series User manual

ENGINE <4G6> 11A............................................
ENGINE <6A1> 11B............................................
ENGINE <4D6> 11C............................................
11A-1
ENGINE
CONTENTS 11109000276

11A-2
ENGINE <4G6>
CONTENTS 11109000603
GENERAL INFORMATION 3..................
SERVICE SPECIFICATIONS 3.................
SEALANTS 4................................
SPECIAL TOOLS 4...........................
ON-VEHICLE SERVICE 6.....................
Drive Belt Tension Check and Adjustment 6......
Ignition Timing Check 7.........................
Idle Speed Check 8............................
Idle Mixture Check 8...........................
Compression Pressure Check 9.................
Manifold Vacuum Check 10.....................
Lash Adjuster Check 11........................
CRANKSHAFT PULLEY 15...................
CAMSHAFT AND CAMSHAFT OIL SEAL 16...
OIL PAN 19..................................
CRANKSHAFT OIL SEAL 20..................
CYLINDER HEAD GASKET 22................
TIMING BELT 26.............................
TIMING BELT B 30...........................
ENGINE ASSEMBLY 33.......................

ENGINE <4G6> - General Information/Service Specifications 11A-3
GENERAL INFORMATION 11100010469
Items 4G63
Total displacement mL 1,997
Bore ´Stroke mm 85.0 ´88.0
Compression ratio 10.0
Combustion chamber Pentroof type
Camshaft arrangement SOHC
Intake 8
Number of valve
Exhaust 8
Opening BTDC 11_
Intake
Closing ABDC 53_
Valve timing
Opening BBDC 63_
Exhaust
Closing ATDC 21_
Fuel system Electronically controlled multipoint fuel injection
Rocker arm Roller type
Auto-lash adjuster Equipped
SERVICE SPECIFICATIONS 11100030489
Items Standard value Limit
When checked 294 - 490 -
Tension N When a used belt is installed 343 - 441 -
Alternator drive When a new belt is installed 490 - 686 -
belt
tension When checked 7.7 - 12.3 -
Deflection
(Reference When a used belt is installed 8.4 - 10.6 -
value) mm
When a new belt is installed 5.9 - 7.7 -
When checked 392 - 588 -
Tension N When a used belt is installed 441 - 539 -
Power steering
oil pump and When a new belt is installed 637 - 833 -
A/C compressor
drive belt When checked 11.7 - 15.3 -
tension Deflection
mm When a used belt is installed 12.5 - 14.3 -
mm
When a new belt is installed 8.8 - 11.0 -
Basic ignition timing 5_BTDC±2_-
Ignition timing Approx. 10_BTDC -

ENGINE <4G6> - Service Specifications/Sealants/Special Tools
11A-4
Items LimitStandard value
Idle speed r/min 750 ±100 -
CO contents % 0.5 or less -
HC contents ppm 100 or less -
Compression pressure (250 - 400 r/min) kPa 1,400 Min. 1,060
Compression pressure difference of all cylinder kPa - Max. 100
Intake manifold vacuum kPa -Min. 69
Cylinder head bolt shank length mm -99.4
Auto-tensioner push rod movement mm Within 1 -
Timing belt tension torque Nm (Reference value) 3.5 -
Auto-tensioner rod protrusion amount mm 3.8 - 4.5 -
Timing belt B tension mm 5-7 -
SEALANTS 11100050201
Items Specified sealants Remarks
Rocker cover and cylinder head
Semi-circular packing
3M ATD Part No.8660 or equivalent -
Oil pan
Thermostat case
MITSUBISHI GENUINE PART
MD970389 or equivalent
Semi-drying sealant
Flywheel bolt 3M Stud Locking 4170 or equivalent -
SPECIAL TOOLS 11100060457
Tool Number Name Use
MB991502 MUT-II sub assem-
bly
DChecking the idle speed
DErasing diagnosis code
MB990767 End yoke holder DHolding the camshaft sprocket
DHolding the crankshaft sprocket
MD998719 or
MD998754
Crankshaft pulley
holder pin
DHolding the camshaft sprocket
DHolding the crankshaft sprocket

ENGINE <4G6> - Special Tools 11A-5
Tool UseNameNumber
MD998713 Camshaft oil seal
installer
Press-in of the camshaft oil seal
MD998443 Auto-lash adjuster
holder
Supporting of auto-lash adjuster
MD998727 Oil pan remover Removal of oil pan
MD998781 Flywheel stopper Securing the flywheel
MD998776 Crankshaft rear oil
seal installer
Press-in of the crankshaft rear oil seal
MB990938 Handle Press-in of the crankshaft rear oil seal
MD998767 Tension pulley
socket wrench
Timing belt tension adjustment
GENERAL
SERVICE
TOOL
MZ203827
Engine lifter Supporting the engine assembly during
removal and installation of the transmission
MB991453 Engine hanger
assembly

ENGINE <4G6> - On-vehicle Service
11A-6
ON-VEHICLE SERVICE 11100090432
DRIVE BELT TENSION CHECK AND
ADJUSTMENT
ALTERNATOR DRIVE BELT TENSION CHECK
Use a belt tension gauge to check that the belt tension is
at the standard value at a point half-way between the two
pulleys as shown in the illustration. In addition, press this
section with a force of 98 N and check that the amount of
belt deflection is at the standard value.
Standard value:
Tension N 294 - 490
Deflection (Reference value) mm 7.7 - 12.3
ALTERNATOR DRIVE BELT TENSION ADJUSTMENT
1. Loosen the nut of the alternator pivot bolt.
2. Loosen the lock bolt.
3. Use the adjusting bolt to adjust the belt tension and belt
deflection to the standard values.
Standard value:
Items When a used
belt is installed
When a new
belt is installed
Tension N 343 - 441 490 - 686
Deflection (Reference
value) mm
8.4 - 10.6 5.9 - 7.7
4. Tighten the nut of the alternator pivot bolt.
Tightening torque: 44 Nm
5. Tighten the lock bolt.
Tightening torque: 22 Nm
6. Tighten the adjusting bolt.
Tightening torque: 10 Nm
Water pump
pulley
Alternator pulley
Crankshaft pulley
Adjusting bolt
Lock bolt

ENGINE <4G6> - On-vehicle Service 11A-7
POWER STEERING OIL PUMP AND AIR CONDITIONER
COMPRESSOR DRIVE BELT TENSION CHECK AND
ADJUSTMENT 11100130127
1. Use a belt tension gauge to check that the belt tension
is at the standard value at a point half-way between the
two pulleys (indicated by an arrow in the illustration).
In addition, press this section with a force of 98 N and
check that the amount of belt deflection is at the standard
value.
Standard value:
Items When
checked
When a
used belt is
installed
When a new
belt is
installed
Tension N 392 - 588 441 - 539 637 - 833
Deflection
(Reference
value) mm
11.7 - 15.3 12.5 - 14.3 8.8 - 11.0
2. If the tension or deflection is outside the standard value,
adjust by the following procedure.
(1) Loosen tensioner pulley fixing nut A.
(2) Adjust the amount of belt deflection using adjusting
bolt B.
(3) Tighten fixing nut A.
Tightening torque: 25 Nm
(4) Check the belt deflection amount and tension, and
readjust if necessary.
Caution
Check after turning the crankshaft once or more
clockwise (right turn).
IGNITION TIMING CHECK 11100170297
1. Before inspection, set the vehicle to the pre-inspection
condition.
2. Connect the MUT-II to the diagnosis connector.
3. Set up a timing light.
4. Start the engine and run at idle.
5. Check that engine idle speed is within the standard value.
Standard value: 750 ±100 r/min
6. Select No.17 of the MUT-II Actuator test.
<VehicleswithoutA/C>
Oil pump pulley
98 N
Crankshaft
pulley
Tensioner pulley
AB
98 N
Crankshaft
pulley
Tensioner
pulley
AB
A/C
compressor
pulley
<VehicleswithA/C>
Oil pump pulley

ENGINE <4G6> - On-vehicle Service
11A-8
7. Check that basic ignition timing is within the standard
value.
Standard value: 5_BTDC±2_
8. If the basic ignition timing is outside the standard value,
inspect the MPI system while referring to GROUP 13A
- Troubleshooting.
9. Press the MUT-II clear key (Select a forced driving cancel
mode) to release the Actuator test.
Caution
If the test is not cancelled, a forced driving will
continue for 27 minutes. Driving under this condition
may damage the engine.
10. Check that ignition timing is at the standard value.
Standard value: approx. 10_BTDC
NOTE
1. Ignition timing is variable within about ±7_, even
under normal operating.
2. And it is automatically further advanced by about
5_from standard value at higher altitudes.
IDLE SPEED CHECK 11100350066
1. Before inspection, set the vehicle to the pre-inspection
condition.
2. Turn the ignition switch to OFF and connect the MUT-II
to the diagnosis connector.
3. Check the basic ignition timing.
Standard value: 5_BTDC±2_
4. Run the engine at idle for 2 minutes.
5. Check the idle speed. Select item No. 22 and take a
reading of the idle speed.
Standard value: 750 ±100 r/min
NOTE
The idle speed is controlled automatically by the idle speed
control (ISC) system.
6. If the idle speed is outside the standard value, inspect
the MPI components by referring to GROUP 13A -
Troubleshooting.
IDLE MIXTURE CHECK 11100210418
1. Before inspection, set the vehicle to the pre-inspection
condition.
2. Turn the ignition switch to OFF and connect the MUT-II
to the diagnosis connector.
3. Check that the basic ignition timing is within the standard
value.
Standard value: 5_BTDC±2_
4. Run the engine at 2,500 r/min for 2 minutes.

ENGINE <4G6> - On-vehicle Service ENGINE <4G6> - On-vehicle Service 11A-9
5. Set the CO, HC tester.
6. Check the CO contents and the HC contents at idle.
Standard value
CO contents: 0.5% or less
HC contents: 100 ppm or less
7. If there is a deviation from the standard value, check
the following items:
DDiagnosis output
DClosed-loop control (When the closed-loop control
is normal, the output signal of the oxygen sensor
changes between 0 - 400 mV and 600 - 1,000 mV
at idle.)
DFuel pressure
DInjector
DIgnition coil, spark plug cable, spark plug
DLeak in the EGR system and in the EGR valve
DEvaporative emission control system
DCompression pressure
NOTE
Replace the three way catalyst when the CO and HC
contents are not within the standard value, even though
the result of the inspection is normal on all items.
COMPRESSION PRESSURE CHECK 11100260499
1. Before inspection, check that the engine oil, starter and
battery are normal. In addition, set the vehicle to the
pre-inspection condition.
2. Disconnect the spark plug cables.
3. Remove all of the spark plugs.
4. Disconnect the crank angle sensor connector.
NOTE
Doing this will prevent the engine-ECU from carrying out
ignition and fuel injection.
5. Cover the spark plug hole with a shop towel etc., and
after the engine has been cranked, check that no foreign
material is adhering to the shop towel.
Caution
1. Keep away from the spark plug hole when
cranking.
2. If compression is measured with water, oil, fuel,
etc., that hascome from cracksinside the cylinder,
these materials will become heated and will gush
out from the spark plug hole, which is dangerous.

ENGINE <4G6> - On-vehicle Service
11A-10
6. Set compression gauge to one of the spark plug holes.
7. Crank the engine with the throttle valve fully open and
measure the compression pressure.
Standard value (at engine speed of 250-400 r/min):
1,400 kPa
Limit (at engine speed of 250-400 r/min):
Min. 1,060 kPa
8. Measure the compression pressure for all the cylinders,
and check that the pressure differences of the cylinders
are below the limit.
Limit: Max. 100 kPa
9. If there is a cylinder with compression or a compression
difference that is outside the limit, pour a small amount
of engine oil through the spark plug hole, and repeat
the operations in steps 7 and 8.
(1) If the compression increases after oil is added, the
cause of the malfunction is a worn or damaged piston
ring and/or cylinder inner surface.
(2) If the compression does not rise after oil is added,
the cause is a burnt or defective valve seat, or pressure
is leaking from the gasket.
10. Connect the crank angle sensor connector.
11. Install the spark plugs and spark plug cables.
12. Use the MUT-II to erase the diagnosis codes.
NOTE
This will erase the diagnosis code resulting from the crank
angle sensor connector being disconnected.
MANIFOLD VACUUM CHECK 11100270409
1. Start the engine and allow it to warm up until the
temperature of the engine coolant reaches 80 to 95_C.
2. Connect a tachometer.
3. Attach a three-way union to the vacuum hose between
the fuel pressure regulator and the air intake plenum,
and connect a vacuum gauge.
4. Start the engine and check that idle speed is within
standard value. Then read off the vacuum gauge.
Limit: Min. 69 kPa
Compression gauge
Vacuum gage