Mitsubishi Grandis. Manual - part 633

ON-VEHICLE SERVICE

ENGINE MECHANICAL

11A-9

CAUTION

• The temperature of the surface of the belt 

should be as close to normal temperature as 
possible.

• Do not allow any contaminants such as water 

or oil to get onto the microphone.

• If strong gusts of wind blow against the 

microphone or if there are any loud sources 
of noise nearby, the values measured by the 
microphone may not correspond to actual 
values.

• If the microphone is touching the belt while 

the measurement is being made, the values 
measured by the microphone may not 
correspond to actual values.

• Do not take the measurement while the 

vehicle's engine is running.

(5) Hold special tool belt tension meter set 

(MB991668) to the middle of the drive belt 
between the pulleys (at the place indicated by 
arrow), approximately 10 

− 20 mm away from 

the rear surface of the belt so that it is 
perpendicular to the belt (within an angle of 

± 

15 degree).

(6) Gently tap the middle of the belt between the 

pulleys (the place indicated by the arrow) with 
your finger as shown in the illustration, and 
measure that the vibration frequency of the 
belt is within the standard value.

Standard value: 109 

− 145 Hz

3. If not within the standard value, replace the 

alternator drive belt auto tensioner. (Refer to 

P.11A-33

).

When using a tension gauge

1. Check the drive belt tension. (Refer to 

P.11A-7

).

2. Use a belt tension gauge in the middle of the belt 

between the pulleys (at the place indicated by the 
arrow) to measure that the belt tension is within 
the standard value.

Standard value: 331 

− 577 N

3. If not within the standard value, replace the 

auto-tensioner. (Refer to 

P.11A-33

).

VALVE CLEARANCE CHECK AND 
ADJUSTMENT

M1111001500164

1. Before inspection, set the vehicle to the 

pre-inspection condition.

2. Turn the ignition switch to the "LOCK" (OFF) 

position.

3. Remove all ignition coils.
4. Remove the rocker cover.
5. Turn the crankshaft clockwise until the notch on 

the pulley is lined up with the "T" mark on the 
timing indicator.

AC301266AB

MB991668

15˚

15˚

10 –

 20 mm

Water 
pump
pulley

Alternator
pulley

Gentry tap 
with your 
finger

AC301267AB

Water pump
pulley

Alternator
pulley

Belt tension 
gauge

ON-VEHICLE SERVICE

ENGINE MECHANICAL

11A-10

6. Move the rocker arms on the No.1 and No.4 

cylinders up and down by hand to determine 
which cylinder has its piston at the top dead 
centre on the compression stroke. If both intake 
and exhaust valve rocker arms have a valve lash, 
the piston in the cylinder corresponding to these 
rocker arms is at the top dead centre on the 
compression stroke.

7. Valve clearance inspection and adjustment can be 

performed on rocker arms indicated by white 
arrow mark when the No.1 cylinder piston is at the 
top dead centre on the compression stroke, and 
on rocker arms indicated by black arrow mark 
when the No.4 cylinder piston is at the top dead 
centre on the compression stroke.

8. Measure the valve clearance.

If the valve clearance is not as specified, loosen 
the rocker arm lock nut and adjust the clearance 
using a thickness gauge while turning the 
adjusting screw.

Standard value (hot engine):

Intake valve: 0.20 mm
Exhaust valve: 0.30 mm

9. While holding the adjusting screw with a 

screwdriver to prevent it from turning, tighten the 
lock nut to the specified torque.

Tightening torque: 9 

± 1 N⋅m

10.Turn the crankshaft through 360 degree angle to 

line up the notch on the crankshaft pulley with the 
"T" mark on the timing indicator.

11.Repeat steps (9) and (10) on other valves for 

clearance adjustment.

12.Install the rocker cover.

13.Install the ignition coils.

ROCKER ARM PISTON OPERATION 
CHECK

M1111051000034

1. Remove all of the ignition coils.
2. Remove the rocker cover.
3. Remove the oil control valve.
4. Remove the taper plug.
5. Turn the crankshaft clockwise until the notch on 

the crankshaft pulley is lined up with "T" mark on 
the lower cover of timing belt.

6. Move the rocker arms on the No.1 and No.4 

cylinders up and down by hand to determine 
which cylinder has its piston at the top dead 
centre on the compression stroke. 

NOTE: 

The rocker arm piston operation check can be 
performed on rocker arms indicated by white arrow 
mark when the No.1 cylinder piston is at the top dead 
centre on the compression stroke, and on rocker 
arms indicated by black arrow mark when the No.4 
cylinder piston is at the top dead centre on the 
compression stroke.

AK204362AE

Exhaust valve side

No. 1 No. 2 No. 3 No. 4

Intake valve side

AK304505AB

Taper plug

Oil  control valve

Ignition coils

Rocker cover

AK303689 AC

Exhaust valve side

Intake valve side

No.  1

No.  2

No.  3

No.  4

ON-VEHICLE SERVICE

ENGINE MECHANICAL

11A-11

7. While shutting up the oil passage hole at the 

depth of the oil control valve's installation hole by 
finger not to leak air, blow compression air into the 
taper plug's installation hole by air blowgun. At 
this time, confirm that the rocker arm piston can 
operate.

NOTE: To fully confirm the check, prevent the 
compression air from leaking as much as possible by 
installing the O-ring to the end of air blowgun.
8. Turn the crankshaft clockwise until the notch on 

the crankshaft pulley is lined up with "T" mark on 
the lower cover of timing belt.

9. Confirm the rest of the rocker arm pistons under 

the procedure 7.

10.When the rocker arm piston does not operate, 

replace the rocker arm assy.

11.Apply sealant to threaded portion.

Specified sealant: LOCTITE203MP or 
equivalent

CAUTION

Do not start the engine within one hour after the 
engine taper plug has been installed.
12.Install the taper plug and tighten to the specified 

torque.

Tightening torque: 10 

± 2 N⋅m

13.Install the oil control valve. (Refer to Camshaft 

and Valve Stem Seal 

− Removal and Installation 

P.11A-16

.)

14.Install the rocker cover.
15.Install all of the ignition coils.

IGNITION TIMING CHECK

M1111001700726

1. Before inspection, set the vehicle to the 

pre-inspection condition.

2. Turn the ignition switch to the "LOCK" (OFF) 

position and then connect the MUT-III to the 
diagnosis connector.

3. Set the timing light to the power supply line 

(terminal No.1) of the ignition coil No.1.
NOTE: The power supply line is looped and also 
longer than the other ones.

4. Start the engine and let it run at idle.
5. Use the MUT-III to measure engine idle speed 

and check that it is within the standard value.

Standard value: 700 

± 100 r/min

6. Select No. 17 of the MUT-III Actuator test.
7. Check that basic ignition timing is within the 

standard value.

Standard value: 5

° BTDC ± 3°

8. If the basic ignition timing is outside the standard 

value, inspect the MPI system (Refer to 

P.13A-20

, 

GROUP 13A 

− Troubleshooting − Inspection 

Chart for Diagnosis Code).

AK302684AC

Rocker arm
piston

Blow
compression
air

Oil passage

Rocker arm

AC302297

AC310120

AB

MB991827

16-pin

MB991910

MB991824

AK305596AB

No. 1 Ignition coil

ON-VEHICLE SERVICE

ENGINE MECHANICAL

11A-12

CAUTION

If the test is not cancelled, a forced driving will 
continue for 27 minutes. Driving under this 
condition may damage the engine.
9. Press the MUT-III clear key (Select a forced 

driving cancel mode) to release the Actuator test.

10.Check that ignition timing is at the standard value.

Standard value: approximately 10

° BTDC

NOTE: 

.

•

The ignition timing may fluctuate within 

±

 7

°

 

BTDC. This is normal.

•

In higher altitude, the ignition timing is more 
advanced than the standard value by 
approximately 5

°

.

11.Remove the timing light.
12.Turn the ignition switch to the "LOCK" (OFF) 

position and then remove the MUT-III.

IDLE SPEED CHECK 

M1111003500728

1. Before inspection, set the vehicle to the 

pre-inspection condition.

2. Turn the ignition switch to the "LOCK" (OFF) 

position and then connect the MUT-III to the 
diagnosis connector.

3. Set the timing light to the power supply line 

(terminal No.1) of the ignition coil No.1.
NOTE: The power supply line is looped and also 
longer than the other ones.

4. Start the engine and let it run at idle.
5. Check that ignition timing is at the standard value.

Standard value: approximately 10

° BTDC

6. Check the idle speed.

Standard value: 700 

± 100 r/min

NOTE: 

.

•

The idle speed is controlled automatically by 
the idle speed control system.

•

When using the MUT-III, select item No. 22 
and take a reading of the idle speed.

7. If the idle speed is outside the standard value, 

inspect the MPI system (Refer to 

P.13A-20

, 

GROUP 13A 

− Troubleshooting − Inspection 

Chart for Diagnosis Code).

8. Turn the ignition switch to the "LOCK" (OFF) 

position and then remove the MUT-III.

IDLE MIXTURE CHECK

M1111002100493

1. Before inspection, set the vehicle to the 

pre-inspection condition.

AC302297

AC310120

AB

MB991827

16-pin

MB991910

MB991824

AK305596AB

No. 1 Ignition coil