length MITSUBISHI 3000GT 1991 Service Manual

GENERAL - General Data and Specifications
GENERAL DATA AND SPECIFICATIONS
00-21
MOOHA- -
c-i----J---i!--8GENERALSPECIFICATIONS
Vehicle dimensionsmm (in.)
Overall length
1
Overall width2
Overall height3
Wheelbase4
Tread
Front5
Rear6
OverhangFront7
Rear8
Minimum running groundclearance9
Angle of approachdegrees10
Angle of departuredegrees11
Vehicle weightkg (tbs.)
Curb weights
MIT
AI-T
Gross vehicle weight rating
Gross axle weight rating
Front
Rear
Seating capacity
Engine
Model No.
Piston displacementcm” (cu.in.)
3000GT
(Non-Turbo)
4,545(178.9)
1,840(72.4)
1,285(50.6)
2,470(97.2)
1,560(61.4)
1,580(62.2)
1,025(40.4)
1,050(41.3)
145(5.7)
12.2”
16.9”
1,455 (3,208)
1,495 (3,296)
1,925 (4,244)
1,100 (2,425)
850 (1.874)
4
6G72-(DOHC)
2,972 (181.4)3000GT SL
(Non-Turbo)
4,545(178.9)
1,840(72.4)
1,285
(50.6)
2,470(97.2)
1,560(61.4)
1,580(62.2)
1,025(40.4)
1,050(41.3)
145(5.7)
12.2”
16.9”
1,520 (3,351)
1,560 (3,439)
1,925 (4.244)
1,100 (2,425)
850 (1,874)
4
6G72-(DOHC) -
2,972 (181.4)
+64
OOFO015
3000GT VR-4
(Turbo)
4,545(I 78.9)
1,840
(72.4)
1,285(50.6)
2,470(97.2)
1,560(61.4)
1,580(62.2)
1,025(40.4)
1,050(41.3)
145 (5.7)
12.2”
16.9”
1,710 (3.770)1,720 (3,792)“’
-
2,050 (4.519)
1,110 (2,447)940
(2,072)
4
6G72-(DOHC)
2,972 (181.4)
NOTE“I : <4ws>
1 TSB Revision

GENERAL - Lubrication and Maintenance00-31LUBRICATION AND MAINTE-
NANCEMOOPA- -
iiMaintenance and lubrication service recommenda-
tions have been compiled to provide maximum
protection for the vehicle owner’s investment
against all reasonable types of driving conditions.
Since these conditions vary with the individual
vehicle owner’s driving habits, the area in which the
vehicle is operated and the type of driving to which
the vehicle is subjected, it is necessary to prescribe
lubrication and maintenance service on a time
frequency as well as mileage interval basis.
Oils, lubricants and greases are classified and
graded according to standards recommended by the
Society of Automotive Engineers
(SAE), the Amer-
ican Petroleum Institute (API) and the National
Lubricating Grease Institute
(NLGI).MAINTENANCE SCHEDULES
Information for service maintenance is provided
under “SCHEDULED MAINTENANCE TABLE”.
Three schedules are provided; one for “Required
Maintenance”, one for “General Maintenance” and
one for “Severe Usage Service”.
Item numbers in the “SCHEDULED MAINTE-
NANCE TABLE” correspond to the item numbers in
the “MAINTENANCE SERVICE” section.
LSEVERE SERVICE
Vehicles operating under severe service conditions
will require more frequent service.
Component service information is included in
appropriate units for vehicles operating under one or
more of the following conditions:
1. Police, taxi, or commercial type operation
2. Operation of Vehicle
(1) Short-trip operation at freezing temperature
(engine not thoroughly warmed up)
(2) More than 50% operation in heavy city
traffic during hot weather above 32°C
(90°F)(3) Extensive idling
(4) Driving in sandy areas
(5) Driving in salty areas
(6) Driving in dusty conditions
ENGINE OIL
The SAE grade number indicates the viscosity of
engine oils, for example, SAE 30, which is a single
grade oil. Engine oils are also identified by a dual
number, for example, SAE 1 OW-30, which indicates
a multigrade oil.
The API classification system defines oil perform-
ance in terms of engine usage. Only engine oil
idesigned “For Service SG” or “For Service
SGXD”,when available, should be used. These oils contain
sufficient chemical additives to provide maximumengine protection. Both the SAE grade and the API
designation can be found on the container.
Caution
Test results submitted to EPA have shown thatlaboratory animals develop skin cancer after
prolonged contact with used engine oil. Accor-dingly, the potential exists for humans to de-
velop a number of skin disorders, including
cancer, from such exposure to used engine oil.
Care should be taken, therefore, when changing
engine oil, to minimize the amount and length ofexposure time to used engine oil on your skin.
Protective clothing and gloves, that cannot be
penetrated by oil, should be worn. The skin
should be thoroughly washed with soap and
water, or use waterless hand cleaner, to removeany used engine oil. Do not use gasoline,
thinners, or solvents.GEAR
LUEiRlCANTSThe SAE grade number also indicates the viscosity
of Multi-Purpose Gear Lubricants.
The API classification system defines gear lubri-
cants in terms of usage. Typically gear lubricants
conforming to API GL-4 or GL-5 with a viscosity of
SAE
75W-85W are recommended for manual trans-
axle.
LUBRICANTS
- GREASES
Semi-solid lubricants, bear the
NLGI designation and
are further classified as grades 0, 1, 2, 3 etc.
Whenever “Chassis Lubricant” is specified,
Multi-Purpose Grease,
NLGI grade 2, should be used.
FUEL USAGE STATEMENT
Use premium unleaded gasoline having a minimum
octane rating of 91,
(R + M)/2. However, it is also
possible to use unleaded gasoline with an octane
rating of at least 87.
Unleaded gasolines only must be used in vehicles
equipped with catalyst emission control systems.
All vehicles, so equipped, have labels located on the
instrument panel and on the back of fuel filler lid that
state, “UNLEADED GASOLINE ONLY”. These vehi-
cles also have fuel filler tubes especially designed to
accept the smaller diameter unleaded gasoline
dispensing nozzles only.
MATERIALS ADDED TO FUEL
Indiscriminate use of fuel system cleaning agents
should be avoided. Many of these materials in-
tended for gum and varnish removal may contain
highly active solvents or similar ingredients that can
be harmful to gasket and diaphragm materials used
in fuel system component parts.
1 TSB Revision

00-42GENERAL - Maintenance Service
14UOO729. Install the radiator cap securely.
10.
Start’the engine and warm up until the thermostat opens.
11. Race the engine up to around 3,000 rpm several times, then
stop the engine.,12. When the enkine has cooled down, remove the radiator cap
L/and add coolant up to the brim. Add coolant to the reserve
tank up to the FULL line.

1. Lift up the vehicle.
2.Loosen the radiator drain plug, remove the drain plug from
the rear bank of the engine and remove the radiator cap to
discharge coolant.
3. Follow the same steps 3 to 12 above.
12.DISC BRAKE PADS (Inspect for wear)MOOSBFDCheck for fluid contamination and wear. Replace complete set
of pads if defective.
Caution
The pads for the right and left wheels should be replaced atIIthe same time. Never “split” or intermix brake pad sets. AllUfour pads must be replaced as a complete set.
Thickness of lining (A):
Limit2.0 mm (.08 in.)
13. BRAKE HOSES (Check for deterioration or
leaks)
MOOSBHBInspection of brake hoses and tubing should be included in all
brake service operations.
The hoses should be checked for:
1.Correct length, severe surface cracking, pulling, scuffing or
worn spots. (If the fabric casing of the hoses is exposed by
cracks or abrasion in the rubber hose cover, the hoses
should be replaced. Eventual deterioration of the hose may
occur with possible bursting failure.)
2. Faulty installation, casing twisting or interference with
wheel, tire or chassis.
14. BALL JOINT AND STEERING LINKAGE SEALS
(Inspect for grease leaks and damage)
MOOSglC1. These components, which are permanently lubricated at
the factory, do not require periodic lubrication. Damaged
seals and boots should be replaced to prevent leakage or
contamination of the grease.
2.Inspect the dust cover and boots for proper sealing, leakageIdand damage. Replace them if defective.
TSB Revision

L’
LENGINE
- Specifications11-5
Items
Standard value
Limit
Cylinder head
Overall height
mm (in.)
132 (5.20)-0.2 (-,008)’
Flatness of gasket surface
mm (in.)Max. 0.03 l.0012)0.2 (.008)
Oversize rework dimension of valveseat hole
mm (in.)
Intake
0.3 f.012) O.S.36.300 - 36.325 (1.4291 - 1.4301)
0.6 l.024) O.S.36.600 - 36.625 (1.4409 - 1.4419)
Exhaust 0.3
l.012) O.S.33.300 - 33.325 (1.31 IO - 1.3120)
0.6 (.024) O.S.33.600 - 33.625 (1.3228 - 1.3238)
Oversize rework dimension of valveseat hole depth
mm (in.)
Intake
0.3 l.012) O.S.7.5 - 7.7 (.295 - ,303)
0.6 t.024) O.S.
7.8 - 8.0 (.307 - ,315)
Exhaust 0.3 t.012) O.S.7.9-8.1 (.311 - ,319)
0.6 (.024) O.S.
8.2 - 8.4 (.323 - .331)
Oversize rework of valve guide hole
(both intake and exhaust)mm (in.)
0.05 f.002) 0,s.13.050- 13.068(.5138-.5145)
0.25 (.OlO) O.S.13.250- 13.268 (.5217- .5224)
0.50 (.020) 0,s.13.500 - 13.518 (.5315 - .5322)
Samshaft
Cam heightmm (in.)
Intake
35.49 (I .3972)34.99 (1.3776)
Exhaust
35.20 (1.3858)
34.70 (1.3661)
Journal O.D.
mm (in.)
26 (1.02)
Bearing oil clearance
mm (in.)0.05 - 0.09 f.0020 - .0035)
Jalve
Valve lengthmm (in.)
Intake
106.3 (4.185)
Exhaust
105.4 (4.150)
Stem O.D.mm (in.)
Intake
6.6 (.260)
Exhaust6.6 i.260)
Face angle
45 - 45.5”Thick;;ss,yf
valve head (Margin)
Intake
1 .o (.039)0.5 (.019)
Exhaust1.5 (.059)1 .o (.039)
Clearance (Valve stem to guide)
mm (in.)
Intake
0.02 - 0.05 (.0008 - .0020)0.10 l.0039)
Exhaust0.05 - 0.09 l.0020 - .0035)0.12 i.0047)
* Limit must be -0.2 mm (--.008 in.) combined with amount of grinding of cylinder block gasket surface.
TSB Revision

11-6ENGINE - Specifications
Items
Valve guide
Lengthmm (in.)
Intake
Exhaust
Service sizemm (in.)Standard value
45.5 (1.791)
50.5 (1.988)
0.05 f.002). 0.25 (.OlO),0.50 f.020) OversizeLimit
Valve seat
Width of seat contactmm (in.)0.9 - 1.3 (.035 - ,051)
Seat angle44 - 44.5”
Valve spring
Free lengthmm (in.)46.9 (1.846)45.9 (1.807)
LoadN (Ibs.)280 (62) at installed height
Installed heightmm (in.)37.9 (1.492)38.9 (1.531)
Squareness1
Less than 2”4”
Cylinder block
Cylinder boremm (in.)
91 .I0
(3.5866)
Out-of-roundness and taper of cylinderLess than 0.02 i.0008)
boremm (in.)
Flatness of gasket surfacemm (in.)
Less than 0.05 t.0020)0.10 (.0039)
Piston0.D mm (in.)
91 .I0 (3.5866)
Clearance (Piston to cylinder)mm (in.)
0.03 - 0.05 (.0012 - .0020)
Ring groove widthmm (in.)
No. 11.2 (.047)
No. 21.5 f.059)
Oil
3.0 (.I 18)
Service sizemm (in.)
0.25 LO1 0),0.50 (.020),0.75 (.030), 1 .oo l.039)Oversize
Piston ring
Side clearancemm (in.)
No. 1
No. 2
End gap
mm (in.)
No. 1
No. 2
Oil ring side railmm (in.)
Service sizemm (in.)
0.03 - 0.07 (.0012 - .0028)
0.02 - 0.06 l.0008 - .0024)
0.30 - 0.45 (.0118 - .0177)
0.45 - 0.60 (.0177 - .0236)
0.20 - 0.60 (.0079 - .0236)
0.25 (.OlO), 0.50 (.020),0.75 (.030), 1 .oo (.039)Oversize
0.1 (.004)
0.1 (.004)
0.8 i.031)
0.8 l.031)
1 .o (.039)
Connecting rod
Bendmm (in.)
Twist
mm (in.)
Big end to thrust clearancemm (in.)
Piston pin press-in load
N (Ibs.)
0.05 i.0020) or less
0.1 (0.004) or less
0.10 - 0.25 (.0039 - .0098)
7,500 - 17,500 (1,686 - 3,934)
0.4 l.016)
1 TSB Revision

ENGINE - Specifications
/
L
L/
Items
Connecting rod bearing
Oil clearancemm (in.)
Crankshaft main bearing
Oil clearancemm (in.)
Crankshaft
Pin O.D.
mm (in.)
Journal O.D.mm (in.)
Out-of-roundness of journal and pin
mm (in.)
Taper of journal and pin
mm (in.)
End playmm (in.)
Oil pressure at curb idle speed
kPa (psi)
[Conditions: oil temperature is 75 to 90°C
(167 to
194”F)l
Standard value
0.016- 0.046 (.0006- .0018)
0.019 - 0.044 (.0007 - .0017)
49.9 (I ,965)
59.9 (2.358)
Less than 0.003 (.00012)
Less than 0.005 (0002)
0.05 - 0.25 (0020 - .0098)
80 (I 1.4) or more
Limit
0.1
(.004)
0.1 (.004)
0.3 (.012)
Oil pump
Side clearancemm (in.)
Body clearance0.100-0.181 (.0039-.0071)
Side clearance0.040 - 0.095 (.0016 - .0037)
Relief spring
Free lengthmm (in.)43.8 (1.724)
Load
137 N (8.3 Ibs.)]mm (in.)40.1 (1.579)
Drive belt
For alternator (Vehicle without air
conditioner)
Deflectionmm (in.)
Inspection
4.0-5.5(.157-,216)
New belt3.5-4.0(.138-,157)
Used belt4.0-5.0 (.157- ,197)
TensionN (Ibs.)
Inspection350 - 600 (77 - 132)
New belt650
- 850 (143 - 187)
Used belt450
- 600 (99 - 132)
For alternator and air conditioner
compressor
Deflectionmm (in.)
Inspection
4.0-5.5(.157-,216)
New belt3.5-4.0 (1388.157)
Used belt4.0-5.0(.157-,197)
For power steering pump
Deflection
mm (in.)9.0
- 11 .o (354 - ,433)
Timing belt
Amount of projection of auto tensioner3.8-4.5(.149-,177)rodmm (in.)(distance between the tensioner arm andauto tensioner body)
1 TSB Revision

ENGINE - Camshaft Oil SealsII-21
r
CamshaftOlM0032
Rear bank6
OlL105C(1) Only
No. 5 bolt in the rear-bank differs from other bolts
in length.
Rear bank No. 5 bolt. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 mm (.79 in.)
Except rear bank No. 5 bolt
_................... 10 mm (.39 in.)
(2) Bolts are color-coded for the front and rear banks as
follows:
Front bank. . . . . . . . . . . . . . . . . .._....___.._______....__.._..._..... I.........Black
Rearbank. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Green(3) When the rocker cover gasket has been replaced,
tighten bolts in this order and then, retighten bolts 1 to 6
to 4 Nm (2.9 ft.lbs.).
1 TSB RevisionSERVICE POINTS OF REMOVALMllZBAG
6. REMOVAL OF CAMSHAFT SPROCKET
Using a wrench at the hexagonal part of the camshaft (to
prevent the crankshaft from turning), loosen the camshaft
sprocket bolt.
CautionDo not hold the camshaft sprocket with a tool, or a
damaged sprocket could result.7. REMOVAL OF CAMSHAFT OIL SEAL
(1) Cut out a portion in the camshaft oil seal lip.
\
(2)Cover the tip of a screwdriver with a cloth and apply it to
the cutout in the oil seal to pry off the oil seal.
Caution
Use care not to damage the camshaft and cylinder
head.SERVICE POINTS OF INSTALLATION
MllZDAI7. INSTALLATION OF CAMSHAFT OIL SEAL
(1) Apply a small amount of engine oil to the oil seal lip.
(2) Using the special tool, insert the oil seal.
6. INSTALLATION OF CAMSHAFT SPROCKET
Using a wrench at the hexagonal part of the camshaft (to
prevent the crankshaft from turning), tighten the camshaft
sprocket bolt.
CautionDo not hold the camshaft sprocket with a tool, or a
damaged sprocket could result.5. INSTALLATION OF ROCKER COVER
Tighten the rocker cover bolts in the order shown in the
illustration.
NOTE’

ENGINE - Cylinder Head Gasket11-25
Rear bank
6 011 010 09
Front bank
6
OlL105C6. INSTALLATION OF INTAKE CAMSHAFT SPROCKET
Using a wrench, hold the camshaft at its hexagon and
tighten the bolt to specification.
Caution
Locking the camshaft sprocket with a tool damages the
sprocket.5. INSTALLATION OF ROCKER COVER
Tighten the rocker cover bolts in the order shown in the
illustration.
NOTE(1) Only No. 5 bolt in the rear bank differs from other bolts
in length.
Rear bank No. 5 bolt._.._.._........._._____.__.._.. 20 mm (.79 in.)
Except rear bank No. 5 bolt
.._._............... 10 mm (.39 in.)
(2) Bolts are color-coded for the front and rear banks as
follows:
Front bank
__.._................_.......................................... Black
Rear bank . . . . . . . . . . ..___..................................._._._.............Green(3) When the rocker cover gasket has been replaced,
tighten bolts in this order, and then retighten bolts 1 to 6
to 4 Nm (2.9 ft.lbs.).
TSB Revision

II-30ENGINE - Timing Belt
hread diameter x length
mm (In.)
6x201.23 x ,781fllllO4F
1 Thread diameter x Lengthmm (in.)
2(39
x1.06)l.47 x 2.50)OlN0072
11. INSTALLATION OF TIMING BELT FRONT COVER (LOW-
ER)Since the mounting bolts of timing cover are different in
size depending on location, insert them with care.
.\J
10. INSTALLATION OF ENGINE SUPPORT BRACKETSince the mounting bolts of engine support bracket are
different in size depending on location, insert them in
numbered sequence.
CautionWhen installing the reamer bolt, tighten it, slowly
spraying lubricant on the reamer area.
\/,,fjd99p54-II5. INSTALLATION OF CRANKSHAFT PULLEY
Using the special tool, attach the crankshaft pulley to the
crankshaft.
CautionUse only the specified special tools, otherwise a
:damaged pulley damper could result.
d
1 TSB Revision1

11-36ENGINE - Cylinder Head and Valve
SquarenssVALVE SPRINGS
(1) Check free length of each valve spring and replace if
necessary.
!
FreelengthStandard value: 46.9 mm
(1.846 in.)\bJLimit: 45.9 mm
(1.807 in.)
(2) Using a square, test squareness of each valve spring. If
spring is excessively out of square, replace it.
Standard value: Less than 2”
Limit: 4
1 EN035
VALVE GUIDES
1 EN29ECheck the valve stem-to-guide clearance. If the clearance
exceeds the service limit, replace the valve guide with new
oversize part.
Standard value:
Intake
Exhaust0.02 - 0.05 mm (0008 - .0020 in.)
Limit:0.05
- 0.09 mm (.0020 - .0035 in.)
Intake
Exhaust0.10 mm (0039 in.)
0.12 mm (0047
in.)6EN043
1AVALVE SEAT RECONDITIONING PROCEDURES
(I 1 Before valve seat reconditioning, check valve stem to guide
clearance.
(2)Recondition the valve seat with a seat grinder or cutter. The
valve seat width should be the specified value at the center
of the valve face.
Inspect the valve seat with prussian blue to determine
LJwhere the valve contacts the seat. To do this, coat valve
seat lightly with prussian blue, and then set valve in place.
Rotate the valve with light pressure. If the blue is
transferred to the center of valve face, contact is satisfac-
tory.
If the blue is transferred to top edge of the valve face, lower
valve seat with a 30 degrees stone or cutter. If the blue is
transferred to the bottom edge of valve face, raise valve
seat with a 65 degrees stone or cutter.
Valve seat diameter:
Intake34 mm (I .34 in.)
ExhaustSeat width: 0.9
29.5 mm (1.16 in.)
- 1.3 mm (035 - .051 in.)
(3) The valve and valve seat should be lapped with a lapping
compound.
VALVE SEAT REPLACEMENT PROCEDURE
(1) Grind the valve seat to be replaced from the inside to thin
the wall thickness. Then, remove the valve seat.
1 ENOE18
TSB Revision