timing MITSUBISHI COLT 2006 Service Repair Manual

GENERAL INFORMATION
ENGINE MECHANICAL <4A9>11A-2
GENERAL INFORMATION
M2112000100697
The newly developed 1.5L 4A91 engine features
4-cylinder, 16-valve, and double overhead camshafts
(DOHC).
The engine has the following features.
•Aluminum cylinder block
•MIVEC (Mitsubishi Innovative Valve timing Elec-
tronic Control system)
•Selective valve tappet of direct acting valve sys-
tem for valve clearance adjustment
•Timing chain
MAJOR SPECIFICATIONS
Item4A91
Total displacement mL1,499
Bore × Stro ke mm75 × 84.8
Compression ratio10.0
Compression chamberPentroof-type
Va l v e t i m i n gIntake openingBTDC 31° − AT D C 1 9°
Intake closingABDC 21° − ABDC 71°
Exhaust openingBBDC 39°
Exhaust closingATDC 5°
Maximum output kW (PS)/rpm77 (104)/6,000
Maximum torque N⋅m (kg⋅m)/rpm141 (14.4)/4,000
Fuel systemElectronically controlled multipoint fuel injection
Ignition systemElectronic-controlled 4-coil

BASE ENGINE
ENGINE MECHANICAL <4A9>11A-10
CRANKSHAFT PULLEY
AK305072AD
Timing markDamper
A cast iron cranksh af t pulley is used.
The pulley has grooves to eng age with a V -rib bed
belt (5
ribs), which drives an alternat or and a water
pump
.
An ignition timing mark (notch) is st amp ed on the
flang
e of the pulley .
The crankshaft pulley is equipped with a to rsio nal
damp
e r to minimize the torsional vibratio n of th e
cranksha
f t as well as sub s t antia lly redu ce no ise and
vib
r ation at the high spee d rang e.
Flyw he el
AK600531
Ring gear
Flywheel
AB
A cast iron ring g ear is a shrink fit in th e iron casting
of
t h e f l yw he el. T h e f l yw he el is in st a l le d by tigh t e n i n g
six bolt
s .

BASE ENGINE
ENGINE MECHANICAL <4A9>11A-12
TIMING CHAIN TRAIN
AK305075
V.V.T. sprocket
AB
V.V.T. sprocket
timing mark
Timing chain mark
link plate (bule)
Camshaft sprocket
Camshaft sprocket
timing mark Timing chain mark
link plate (bule)
Timing chain mark
link plate (bule)
Crankshaft
sprocket
timing mark
Crankshaft sprocket
Timing mark
Timing chain
tensioner
Tensioner lever
Chain guide
Timing mark
The 2 camshaf
t s are driven by the t i ming chain via
the res
pec tive spro cke t s .
The timing cha i n, consist i ng o f 122 links, is an end-
less chain, conn ecting the cran ksh af t spro cke t with
the camshaf
t and V . V . T . spro cke t s .
The timing cha i n is eq uippe d with 3 mark link p l ates
(blue)
to co rrectly time t he 3 sprocket s with each
other
.
ItemNo. of
teeth
Camshaft sprocket36
V.V.T. sprocket36
Crankshaft sprocket18
TIMING CHAIN TENSIONER
AK305388AB
Retainer
Ball
Coil spring 1
Ball sheet
Coil spring 2
Cam
Pin
Plunger
The timing chain is tensione
d by th e timing chain te n-
sioner , which ha s a b u ilt-in plunge r with plunge r
springs.
The plunger in the timing chain tension e r dire ctly
push
e s th e tension lever , and the pre s sure aut omati
-
cally ad just s the timing chain tension.
A cam is provided t o lock th e plu nger in pla c e a f te r
the eng
ine stop s. This help s prevent the timing chain
from wob
b lin g just af ter th e eng ine st a r t s .
With the timing cha i n ten s io ner in st alled, do not
crank the
engin e in the reverse directio n. This will
force
the plunger to overcome the cam, or e v en
cause oth
e r problems.

BASE ENGINE
ENGINE MECHANICAL <4A9>11A-15
MIVEC (MITSUBISHI INNOVATIVE VALVE TIMING ELECTRONIC CONTROL SYSTEM)
AK300856AD
A
A
A-A
Oil feeder control valve
Oil feeder
control
valve filter
Oil feeder
control
valve filter
bolt
Cylinder head
Cylinder block
V.V.T.sprocket
M I VEC (Mit su bis h i Inn o va tive V a lve tim i ng Elect r o n ic
Con
t rol system) consist s of th e compon ent s illus
-
trated above .
The int a ke valve timing is optimally controlled (con-
tinuously variable) un der the chan ging driving condi-
tions to improv e po we r in th e entire sp eed ra nge.
V. V . T . SPROCKET (V ARIABLE V A L V E TIMING SPROCKET)
AK300857
Vane bushing
AB
SprocketVane roter
V.V.T.sprocket
bolt
Timing mark
Vane housing
Advance oil chamber
Retard oil chamber
Stopper pin
Oil from the oil fe
eder control valve is sent t o the
V
. V . T . sp rocket, moving the vane roto r and thus reg u
-
lating the valve timing.

BASE ENGINE
ENGINE MECHANICAL <4A9>11A-17
TIMING CHAIN CASE
AK305243
Engine support bracket
AB
The engine supp ort bracket, the oil pu mp a nd the
relie
f valve are in tegrate d as we ll as water chamber
of the wat
e r pump.

GENERAL INFORMATION
ENGINE MECHANICAL <4A9>11A-18
GENERAL INFORMATION
M2112000101009
The newly developed 1.5L 4A91 engine features
4-cylinder, 16-valve, and double overhead camshafts
(DOHC).
The engine has the following features.
•Aluminum cylinder block
•MIVEC (Mitsubishi Innovative Valve timing Elec-
tronic Control system)
•Selective valve tappet of direct acting valve sys-
tem for valve clearance adjustment
•Timing chain
MAJOR SPECIFICATIONS
Item4A91
Total displacement mL1,499
Bore × Stro ke mm75 × 84.8
Compression ratio10.0
Compression chamberPentroof-type
Va l v e t i m i n gIntake openingBTDC 31° − AT D C 1 9°
Intake closingABDC 21° − ABDC 71°
Exhaust openingBBDC 39°
Exhaust closingATDC 5°
Maximum output kW (PS)/rpm77 (104)/6,000
Maximum torque N⋅m (kg⋅m)/rpm141 (14.4)/4,000
Fuel systemElectronically controlled multipoint fuel injection
Ignition systemElectronic-controlled 4-coil

BASE ENGINE
ENGINE MECHANICAL <4A9>11A-26
CRANKSHAFT PULLEY
AK305072AD
Timing markDamper
A cast iron cranksh af t pulley is used.
The pulley has grooves to eng age with a V -rib bed
belt (5
ribs), which drives an alternat or and a water
pump
.
An ignition timing mark (notch) is st amp ed on the
flang
e of the pulley .
The crankshaft pulley is equipped with a to rsio nal
damp
e r to minimize the torsional vibratio n of th e
cranksha
f t as well as sub s t antia lly redu ce no ise and
vib
r ation at the high spee d rang e.
Flyw he el
AK600531
Ring gear
Flywheel
AB
A cast iron ring g ear is a shrink fit in th e iron casting
of
t h e f l yw he el. T h e f l yw he el is in st a l le d by tigh t e n i n g
six bolt
s .

BASE ENGINE
ENGINE MECHANICAL <4A9>11A-28
TIMING CHAIN TRAIN
AK305075
V.V.T. sprocket
AB
V.V.T. sprocket
timing mark
Timing chain mark
link plate (bule)
Camshaft sprocket
Camshaft sprocket
timing mark Timing chain mark
link plate (bule)
Timing chain mark
link plate (bule)
Crankshaft
sprocket
timing mark
Crankshaft sprocket
Timing mark
Timing chain
tensioner
Tensioner lever
Chain guide
Timing mark
The 2 camshaf
t s are driven by the t i ming chain via
the res
pec tive spro cke t s .
The timing cha i n, consist i ng o f 122 links, is an end-
less chain, conn ecting the cran ksh af t spro cke t with
the camshaf
t and V . V . T . spro cke t s .
The timing cha i n is eq uippe d with 3 mark link p l ates
(blue)
to co rrectly time t he 3 sprocket s with each
other
.
ItemNo. of
teeth
Camshaft sprocket36
V.V.T. sprocket36
Crankshaft sprocket18
TIMING CHAIN TENSIONER
AK305388AB
Retainer
Ball
Coil spring 1
Ball sheet
Coil spring 2
Cam
Pin
Plunger
The timing chain is tensione
d by th e timing chain te n-
sioner , which ha s a b u ilt-in plunge r with plunge r
springs.
The plunger in the timing chain tension e r dire ctly
push
e s th e tension lever , and the pre s sure aut omati
-
cally ad just s the timing chain tension.
A cam is provided t o lock th e plu nger in pla c e a f te r
the eng
ine stop s. This help s prevent the timing chain
from wob
b lin g just af ter th e eng ine st a r t s .
With the timing cha i n ten s io ner in st alled, do not
crank the
engin e in the reverse directio n. This will
force
the plunger to overcome the cam, or e v en
cause oth
e r problems.

BASE ENGINE
ENGINE MECHANICAL <4A9>11A-31
MIVEC (MITSUBISHI INNOVATIVE VALVE TIMING ELECTRONIC CONTROL SYSTEM)
AK300856AD
A
A
A-A
Oil feeder control valve
Oil feeder
control
valve filter
Oil feeder
control
valve filter
bolt
Cylinder head
Cylinder block
V.V.T.sprocket
M I VEC (Mit su bis h i Inn o va tive V a lve tim i ng Elect r o n ic
Con
t rol system) consist s of th e compon ent s illus
-
trated above .
The int a ke valve timing is optimally controlled (con-
tinuously variable) un der the chan ging driving condi-
tions to improv e po we r in th e entire sp eed ra nge.
V. V . T . SPROCKET (V ARIABLE V A L V E TIMING SPROCKET)
AK300857
Vane bushing
AB
SprocketVane roter
V.V.T.sprocket
bolt
Timing mark
Vane housing
Advance oil chamber
Retard oil chamber
Stopper pin
Oil from the oil fe
eder control valve is sent t o the
V
. V . T . sp rocket, moving the vane roto r and thus reg u
-
lating the valve timing.

BASE ENGINE
ENGINE MECHANICAL <4A9>11A-33
TIMING CHAIN CASE
AK305243
Engine support bracket
AB
The engine supp ort bracket, the oil pu mp a nd the
relie
f valve are in tegrate d as we ll as water chamber
of the wat
e r pump.