Mitsubishi 6M70 Instruction manual

14
13
12
00
11
GROUP INDEX
15
17
GENERAL .............................................
ENGINE .................................................
LUBRICATION ......................................
FUEL AND ENGINE CONTROL ...........
COOLING ..............................................
INTAKE AND EXHAUST.......................
EMISSION CONTROL ..........................
Applicable models
Mitsubishi 6M70
Workshop
Manual
diesel engine
Mitsubishi 6M70
APPLICABLE SERVFICE BULLETINS FOR
THIS MANUAL INDEX

00-22
1. Diagnosis Codes
•Diagnosis codes indicate the faulty sections of the vehicle.
•A fault can be repaired by reading out the diagnosis code(s) stored in the control unit and performing the remedy
for that code(s).
•Diagnosis codes can be displayed in the following two methods. Select either of them according to the system to
be diagnosed.
•Using a Multi-Use Tester
•Using flashing of a warning lamp on meter cluster
•The table below indicates the systems for which diagnosis codes can be displayed and the methods usable for in-
dividual systems.
1.1 Systems and diagnosis code displaying methods
1.2 Types of diagnosis codes
•There are two types of diagnosis code output method depending on the system: one has a distinction of present
and past codes, and the other does not have such a distinction.
(1) The system that has a distinction of present and past diagnosis codes
(1.1) Present diagnosis code
•Fault developed in the vehicle after the starter switch is set to ON is indicated by corresponding diagnosis code.
•The fault warning lamp is lit at the same time.
(1.2) Past diagnosis code
•Past fault developed in the vehicle is indicated by corresponding diagnosis code stored in the memory of the elec-
tronic control unit.
•With the vehicle restored to its normal condition or the starter switch turned from OFF to ON after inspection or re-
pair against present diagnosis codes, the present diagnosis code is stored as past diagnosis codes in the memory
of the electronic control unit.
•When reading out the past diagnosis codes, the warning lamp does not illuminate as such codes do not indicate
the current fault.
(2) The system that does not have a distinction of present and past diagnosis codes
•The present and past diagnosis codes are displayed together without distinction.
Warning
lamp System
Diagnosis codes
displaying methods Reference
Gr
Multi-Use
Tester
Flashing of
warning lamp
Common rail
OO
13
Turbocharger 15
Exhaust gas recirculation 17
Starter continuous energizing preventing function 54
Vehicle speed limiting (SLD) OO54
Auto cruise
– Full auto air conditioner O O 55
System Diagnosis code
With distinction of present and past Without distinction
Except below O –
Full auto air conditioner – O
DIAGNOSIS CODES

00
00-23
2. Reading and Erasing the Diagnosis Code
2.1 Using a Multi-Use Tester
(1) Connecting a Multi-Use Tester
Special tools
Mark Tool name and shape Part No. Application
Multi-Use Tester III
SOFTWARE DISC
FMS-E07-3*
(Multi-Use
Tester-III ver-
sion)
Installation of the Muti-Use-Tester-III
or version-up of the current version
into Multi-Use Tester-III SOFTWARE
DISC (Pub. No. SG0705A)
V.C.I. MH062927 Data transmission between electronic
control unit and PC
Multi-Use Tester test
Harness E
A: Harness for inspec-
tion and drive recorder
B: Harness for drive re-
corder
C: Drive recorder har-
ness
D: Cigarette lighter
plug harness
MH063659
A: MH063661
B: MH063663
C: MH063665
D: MH063666
Power supply to V.C.I. and communi-
cation with electronic control unit
Multi-Use Tester test
harness D
(used for extension)
MH062951 Multi-Use Tester test harness B ex-
tension
USB cable MH063668 Communication between V.C.I. and
PC
SOFTWARE DISC

00-24
(1.1) To perform system inspection
•Move the starter switch to the LOCK position.
•Connect PC installed , , -A and as shown.
•Connect -A connector to the Multi-Use Tester connector on
the vehicle.
(1.2) To use drive recorder function
•Move the starter switch to the LOCK position.
•Connect PC installed , , -A, -C, -D and
as shown.
•Connect -C connector to the Multi-Use Tester connector on
the vehicle.
•Connect the cigarette lighter plug of -D to the cigarette light-
er socket on the vehicle.
(1.3) To extend the Multi-Use Tester test harness
•Connect to -A to extend the test harness to use the
Multi-Use Tester outside the vehicle.
DIAGNOSIS CODES

00
00-25
(2) Access of diagnosis code
•Set the starter switch to ON.
•Operate the Multi-Use Tester for a display of necessary diagnosis code stored in the memory of the electronic
control unit and identify the location of the fault.
(3) Clearing of diagnosis code
•Set the starter switch to ON (the engine not to be started).
•Operate the Multi-Use Tester to delete all the diagnosis codes stored in the memory of the electronic control unit.
2.2 Using flashing of a warning lamp on meter cluster
(1) Engine control, vehicle speed limiting (SLD), auto cruise
•Using the diagnosis and memory clear switches, display diagnosis codes.
CAUTION
• Opening the memory clear switch followed by its reconnection will erase the stored diagnosis codes from
the memory. To avoid inadvertently erasing necessary codes, be sure to read well the procedure de-
scribed below before handling diagnosis codes.

00-26
(1.1) Reading diagnosis codes
•To read a diagnosis code, observe how may times the warning
lamp flashes and how long each illumination lasts.
•The duration of illumination differs between the first and second
digits.
•Second digit: 1.2 sec.
•First digit: 0.4 sec.
•A diagnosis code consists of the flashing of second digit and the
flashing of first digit in that order. If a diagnosis code has “0” in
the second digit, only the first digit will be displayed.
•The diagnosis code 01 will be displayed if the system is normal.
•The same diagnosis code will be displayed 3 times in a row be-
fore moving to the display of the next code.
•After the last diagnosis code is displayed, the first code will be
displayed again 3 times in a row and then the subsequent
codes. This will be repeated.
(1.2) Present diagnosis codes
•Turn the starter switch ON.
•Remove the diagnosis switch.
•Present diagnosis codes will be displayed by flashing of the
warning lamp.
•When the diagnosis switch is connected, electronic control unit
will stop (terminate) displaying diagnosis codes.
(1.3) Present and past diagnosis codes
•Turn the starter switch to the ON position.
•Open the diagnosis switch.
•Present diagnosis codes will be displayed by flashing of the
warning lamp.
•Open the memory clear switch.
•Present and past diagnosis codes will be displayed by flashing
of the warning lamp.
•Turn the starter switch to the OFF position and connect the
memory clear switch and diagnosis switch to terminate the diag-
nosis code displaying mode.
(1.4) Erasing diagnosis codes
•Turn the starter switch to the ON position (do not start the en-
gine).
•Open the memory clear switch and reconnect it; all diagnosis
codes stored in electronic control unit memory will be erased.
To cancel diagnosis code erasure after opening the memory
clear switch, turn the starter switch to the OFF position and then
reconnect the memory clear switch.
DIAGNOSIS CODES

00
00-27
(2) Full automatic air conditioner
(2.1) Connection of LED for inspec-
tion
•Move the starter switch to the LOCK
position.
•Connect the LED for inspection to the
Multi-Use Tester connector.
CAUTION
• Air conditioner electronic control
unit and control panel has a backup
power supply to keep diagnostic
check results in memory. If this
power supply is cut off, with battery
cables disconnected, for example,
stored data are erased.
• Air conditioner electronic control
unit and control panel enters into
the mode of control during fault im-
mediately a fault occurs. In this
mode, control is effected to mini-
mize trouble arising from the fault.
(2.2) Reading and erasing diagnosis codes
•To read a diagnosis code, observe how may times the LED for
inspection flashes and how long each illumination lasts.
•The duration of illumination differs between the first and second
digits.
•Second digit: 1.5 sec.
•First digit: 0.5 sec.
•A diagnosis code consists of the flashing of second digit and the
flashing of first digit in that order. If a diagnosis code has “0” in
the second digit, only the first digit will be displayed.
•When two or more faults occur at a time, relevant diagnosis
codes are displayed repeatedly starting from the first Code.
•To erase a diagnosis code from the memory after inspection,
disconnect negative (–) battery cable and leave it disconnected
for more than 30 seconds.

00-28
•Use specified bolts and nuts. Tighten them to the torques shown below as appropriate, unless otherwise speci-
fied.
•Threads and bearing surfaces shall be dry.
•If the mating nut and bolt (or stud bolt) are different in level of strength, tighten them to the torque specified for the
bolt.
Hexagon Head Bolts and Stud Bolts (Unit: N·m {kgf·m})
Hexagon Head Flange Bolts (Unit: N·m {kgf·m})
Strength 4T 7T 8T
Identification
symbol
Nominal
diameter (stud) (stud) (stud)
M5 2 to 3
{0.2 to 0.3} –4 to 6 {0.4 to 0.6} –5 to 7 {0.5 to 0.7} –
M6 4 to 6
{0.4 to 0.6} –7 to 10 {0.7 to 1.0} –8 to 12 {0.8 to 1.2} –
M8 9 to 13
{0.9 to 1.3} –16 to 24
{1.7 to 2.5} –19 to 28
{2.0 to 2.9} –
M10 18 to 27
{1.8 to 2.7}
17 to 25
{1.8 to 2.6}
34 to 50
{3.5 to 5.1}
32 to 48
{3.3 to 4.9}
45 to 60
{4.5 to 6.0}
37 to 55
{3.8 to 5.7}
M12 34 to 50
{3.4 to 5.1}
31 to 45
{3.1 to 4.6}
70 to 90
{7.0 to 9.5}
65 to 85
{6.5 to 8.5}
80 to 105
{8.5 to 11}
75 to 95
{7.5 to 10}
M14 60 to 80
{6.0 to 8.0}
55 to 75
{5.5 to 7.5}
110 to 150
{11 to 15}
100 to 140
{11 to 14}
130 to 170
{13 to 17}
120 to 160
{12 to 16}
M16 90 to 120
{9 to 12}
90 to 110
{9 to 11}
170 to 220
{17 to 23}
160 to 210
{16 to 21}
200 to 260
{20 to 27}
190 to 240
{19 to 25}
M18 130 to 170
{14 to 18}
120 to 150
{12 to 16}
250 to 330
{25 to 33}
220 to 290
{23 to 30}
290 to 380
{30 to 39}
250 to 340
{26 to 35}
M20 180 to 240
{19 to 25}
170 to 220
{17 to 22}
340 to 460
{35 to 47}
310 to 410
{32 to 42}
400 to 530
{41 to 55}
360 to 480
{37 to 49}
M22 250 to 330
{25 to 33}
230 to 300
{23 to 30}
460 to 620
{47 to 63}
420 to 560
{43 to 57}
540 to 720
{55 to 73}
490 to 650
{50 to 67}
M24 320 to 430
{33 to 44}
290 to 380
{29 to 39}
600 to 810
{62 to 83}
540 to 720
{55 to 73}
700 to 940
{72 to 96}
620 to 830
{63 to 85}
Strength 4T 7T 8T
Identification
symbol
Nominal
diameter
M6 4 to 6
{0.4 to 0.6} –8 to 12 {0.8 to 1.2} –10 to 14 {1.0 to 1.4} –
M8 10 to 15
{1.0 to 1.5} –19 to 28
{2.0 to 2.9} –22 to 33
{2.3 to 3.3} –
M10 21 to 31
{2.1 to 3.1}
20 to 29
{2.0 to 3.0}
45 to 55
{4.5 to 5.5}
37 to 54
{3.8 to 5.6}
50 to 65
{5.0 to 6.5}
50 to 60
{5.0 to 6.5}
M12 38 to 56
{3.8 to 5.5}
35 to 51
{3.5 to 5.2}
80 to 105
{8.0 to 10.5}
70 to 95
{7.5 to 9.5}
90 to 120
{9 to 12}
85 to 110
{8.5 to 11}
TABLE OF STANDARD TIGHTENING TORQUES

00
00-29
Hexagon Nuts (Unit: N·m {kgf·m})
Hexagon Flange Nuts (Unit: N·m {kgf·m})
Strength 4T 6T
Identification
symbol
Nominal
diameter
Standard screw
thread
Coarse screw
thread Standard screw thread Coarse screw thread
M5 2 to 3
{0.2 to 0.3} –4 to 6 {0.4 to 0.6} –
M6 4 to 6
{0.4 to 0.6} –7 to 10
{0.7 to 1.0} –
M8 9 to 13
{0.9 to 1.3} –16 to 24 {1.7 to 2.5} –
M10 18 to 27
{1.8 to 2.7}
17 to 25
{1.8 to 2.6}
34 to 50
{3.5 to 5.1}
32 to 48
{3.3 to 4.9}
M12 34 to 50
{3.4 to 5.1}
31 to 45
{3.1 to 4.6}
70 to 90
{7.0 to 9.5}
65 to 85
{6.5 to 8.5}
M14 60 to 80
{6.0 to 8.0}
55 to 75
{5.5 to 7.5}
110 to 150
{11 to 15}
100 to 140
{11 to 14}
M16 90 to 120
{9 to 12}
90 to 110
{9 to 11}
170 to 220
{17 to 23}
160 to 210
{16 to 21}
M18 130 to 170
{14 to 18}
120 to 150
{12 to 16}
250 to 330
{25 to 33}
220 to 290
{23 to 30}
M20 180 to 240
{19 to 25}
170 to 220
{17 to 22}
340 to 460
{35 to 47}
310 to 410
{32 to 42}
M22 250 to 330
{25 to 33}
230 to 300
{23 to 30}
460 to 620
{47 to 63}
420 to 560
{43 to 57}
M24 320 to 430
{33 to 44}
290 to 380
{29 to 39}
600 to 810
{62 to 83}
540 to 720
{55 to 73}
Strength 4T
Identification
symbol
Nominal
diameter
Standard screw
thread
Coarse screw
thread
M6 4 to 6
{0.4 to 0.6} –
M8 10 to 15
{1.0 to 1.5} –
M10 21 to 31
{2.1 to 3.1}
20 to 29
{2.0 to 3.0}
M12 38 to 56
{3.8 to 5.6}
35 to 51
{3.5 to 5.2}

00-30
Tightening Torque for General-Purpose Flare Nut (Unit: N·m {kgf·m})
Tightening Torque for General-Purpose Air Piping Nylon Tube (DIN Type) (Unit: N·m
{kgf·m})
Tightening Torque for General-Purpose Air Piping Nylon Tube (SAE Type) (Unit: N·m
{kgf·m})
Pipe diameter φ4.76 mm φ6.35 mm φ8 mm φ10 mm φ12 mm φ15 mm
Tightening torque 17 {1.7} 25 {2.6} 39 {4.0} 59 {6.0} 88 {9.0} 98 {10}
Nominal diameter
×wall thickness 6 ×1 mm 10 ×1.25 mm 12 ×1.5 mm 15 ×1.5 mm
Tightening torque 20 {2.0 } 34 {3.5 } 49 {5.0 } 54 {5.5 }
Nominal diameter 1/4 in. 3/8 in. 1/2 in. 5/8 in.
Tightening torque 13 {1.3 } 29 {3.0 } 49 {5.0 } 64 {6.5 }
+6
0
+0.6
0
+10
0
+1.0
0
+10
0
+1.0
0
+5
0
+0.5
0
+4
0
+0.4
0
+5
0
+0.5
0
+5
0
+0.5
0
+5
0
+0.5
0
TABLE OF STANDARD TIGHTENING TORQUES

11-1
GROUP 11 ENGINE
SPECIFICATIONS .............................................................................. 11-2
STRUCTURE AND OPERATION
1. Engine Proper .................................................................................... 11-3
2. Rocker and Shaft, Camshaft, Rocker Case and
Cylinder Head Gasket ....................................................................... 11-4
3. Valve Mechanism ............................................................................... 11-4
4. Connecting Rod ................................................................................. 11-5
5. Piston .................................................................................................. 11-5
6. Timing Gears ...................................................................................... 11-6
7. Flywheel ............................................................................................. 11-6
8. Flywheel PTO ..................................................................................... 11-7
9. Powertard Brake System .................................................................. 11-8
TROUBLESHOOTING ..................................................................... 11-12
ON-VEHICLE INSPECTION AND ADJUSTMENT
1. Measuring Compression Pressure ................................................ 11-14
2. Inspection and Adjustment of Valve Clearances .......................... 11-16
3. Inspection and Adjustment of Powertard Clearances ................. 11-20
ENGINE REMOVAL AND INSTALLATION ...................................... 11-22
ROCKER COVER, ROCKER AND SHAFT ..................................... 11-26
CAMSHAFT AND ROCKER CASE ................................................. 11-30
CYLINDER HEAD AND VALVE MECHANISM ................................ 11-38
PISTON, CONNECTING ROD AND CYLINDER LINER ................. 11-54
FLYWHEEL PTO <WITH FLYWHEEL PTO> ................................... 11-68
FLYWHEEL ...................................................................................... 11-72
TIMING GEARS
<WITHOUT FLYWHEEL PTO>...................................................... 11-78
<WITH FLYWHEEL PTO> ............................................................ 11-82
CRANKSHAFT AND CRANKCASE ................................................. 11-88

11-2
Item Specifications
Engine type 6M70T2 6M70T4
Type 6-cylinder, in-line, water-cooled, 4-cycle diesel engine
Combustion chamber Direct injection type
Valve mechanism Overhead camshaft (OHC) system
Maximum output kW {PS} /rpm 257 {350} / 2000 309 {420} / 2000
Maximum torque N·m {kgf·m} /rpm 1620 {165} / 1100 1810 {185} / 1100
Cylinder bore ×stroke mm φ135 ×150
Total displacement cm3{L} 12882 {12.882}
Compression ratio 17.5
SPECIFICATIONS
Mitsubishi 6M70 Engine Parts contact:
email: [email protected]
Phone: [phone]

11
11-3
1. Mitsubishi 6M70 Engine Proper
•The 6M70engine employs an overhead camshaft (OHC) system, with the valve mechanism and the timing
gears arranged as shown above.
STRUCTURE AND OPERATION

11-4
2. Rocker and Shaft, Camshaft, Rocker Case and Cylinder Head Gasket
•The camshaft journals are directly
supported by the rocker case and the
camshaft cap, without using any cam-
shaft bearings. The rocker case and
camshaft caps have been machined
together, meaning that they all need to
be replaced for a new set when one of
them becomes defective.
3. Valve Mechanism
•Each valve has a valve stem seal, which regulates the flow of lubricating oil to the contact surface between the
valve and the valve guide.
•The valve springs have a variable pitch to prevent abnormal vibration at high engine speed. The exhaust valves
use a double spring, with the inner and outer springs coiled in different directions to prevent them from jamming
each other.
STRUCTURE AND OPERATION

11
11-5
4. Mitsubishi 6M60 Connecting Rod
•Weight mark: “A” to “H”, “J” to “M”
•“A” indicates the greatest connecting
rod mass.
5. Mitsubishi 6M70 Piston

11-6
6. Mitsubishi 6M70 Timing Gears
•The timing gears are provided with
timing marks to help ensure correct
assembly.
•Timing marks are provided on the fol-
lowing gears.
•Camshaft gear: stamped line
•Crankshaft gear: “A”
•Idler gear A, B: “A”, “B”
•Idler gear C: “B”, “C”
•Supply pump gear: “C”
7. Flywheel
STRUCTURE AND OPERATION

11
11-7
8. Flywheel PTO
•The flywheel PTO is located in the upper part of the flywheel housing and is driven by the PTO drive gear.

11-8
9. Powertard Brake System
•The Powertard is activated when all of the following conditions are met with the combination switch placed in the
first stage or second stage.
•Engine speed: 800 to 2400 rpm
•Clutch pedal released (clutch pedal switch: OFF)
•Accelerator pedal released (accelerator pedal switch: ON)
•Transmission in gear (transmission neutral switch: ON)
•Anti-lock brake system not activated (ABS) (Control unit: OFF) (See Gr35E.)
•If any of the above conditions are not met, operation of the Powertard system will be temporarily canceled.
If the engine speed is less than 700 rpm or higher than 2500 rpm although all the other conditions (clutch pedal,
accelerator pedal, and transmission conditions) are met, operation of the Powertard system will be canceled.
•When the vehicle speed exceeds the auto cruise set vehicle speed during driving with the auto cruise engaged,
the Powertard is activated by the control of the engine electronic control unit even if the Powertard switch (combi-
nation switch) is not turned ON. (See Gr13.)
•When the Powertard switch is placed in the first stage, the Powertard is activated to enhance the engine braking
power.
•When the Powertard switch is placed in the second stage, the turbocharger magnetic valve is activated to control
the turbocharger and generate stronger braking power than the first stage.
STRUCTURE AND OPERATION

11
11-9
9.1 Operation of Powertard brake system
•The Powertard brake system is a device to enhance the engine brake performance. It opens and closes the ex-
haust valve (one side only) to control the volume of compressed air in the combustion chamber in accordance
with the movement of the piston, thereby providing a boosted braking force. Powertard components are located in
the cylinder head.
•The valve bridge is provided with an adjusting screw and a pin that allow the exhaust valve to be opened and
closed under the control of the Powertard, in addition to ordinary valve control.
•The pin is free to move in the adjusting screw. Its movement is controlled by the control valve.
•The adjusting screw is used to adjust the timing (Powertard clearance) for the control valve to press the pin.
(1) Operating principle
•In the ordinary engine brake, the piston is forced up during its
compression stroke when compressed air A develops a counter
force B to press the piston. This force works as a braking force.
However, the piston is forced down during its expansion stroke
to let compressed air expand. This causes an accelerating force
C to work on the piston downward, resulting in the braking force
obtained during the compression period being lost largely.

11-10
•When the Powertard system is activated, the piston pressing
force works as a braking force during the compression stroke as
when the Powertard system is not activated. During the expan-
sion period, the exhaust valve is opened by the working of the
system to let some of the compressed air out through the ex-
haust port.
•This causes the piston pressing force to be no longer generated.
As a result, the braking force obtained during the compression
period is maintained for effective use.
•After letting out more compressed air, the exhaust valve is
closed, which causes the combustion chamber to be closed up.
As a result, during the expansion period, a new force is generat-
ed which hinders the movement of piston when it goes down.
This force, following the braking force obtained during the previ-
ous compression period, also acts as a braking force, enhancing
greatly the vehicle’s engine brake capacity.
The operation of the system which causes the valve to be
opened and closed in agreement with the successive piston
strokes is called synchronized operation.
•As shown above, when the Powertard system is activated, the
engine brake provides more power than the ordinary engine
brake.
(2) Hydraulic pressure control
•When the solenoid valve is activated,
engine oil (oil pressure produced by
ordinary engine oil pump) is let in from
A to flow through the oil passage and
forces open the check valve in the
control valve.
•Oil pressure proceeds through the oil
passage to move the master piston
into contact with the dedicated Power-
tard cam.
•This allows the rotation of the dedicat-
ed Powertard cam to be transmitted to
the master piston. As the cam lobe top
is reached, oil pressure in the oil pas-
sage further builds up, forcing the
check valve in the control valve to
close and working on the slave piston
at the same time.
•The slave piston pushes the pin, which
in turn forces the exhaust valve to
open. As a result, the pressure in the
combustion chamber is released to
maintain effective braking force.
STRUCTURE AND OPERATION