MITSUBISHI 3000GT 1991 Workshop Manual

11-I
ENGINECONTENTS
IMllAA--
CAMSHAFT OIL SEALS....................................
CRANKSHAFT, FLYWHEEL AND
DRIVEPLATE........................................................
CYLINDER BLOCK................................................
CYLINDER HEAD AND VALVE........................
CYLINDER HEAD GASKET................................
ENGINE ASSEMBLY............................................
ENGINE OIL COOLER........................................
GENERAL INFORMATION................................
lbLubricationSystem............................................SectionalView
....................................................
OIL PAN AND OIL PUMP....................................
OIL PAN AND OIL SCREEN................................20
49
5334
23
17
552
3
240
22
PISTON AND CONNECTING ROD....................
ROCKER ARM AND CAMSHAFT....................
SERVICE ADJUSTMENT PROCEDURES........Compression Pressure Check
........................Curb Idle Speed Inspection
............................Drive Belts Tension Adjustment
....................Ignition Timing Adjustment
............................
LashAdjusters
Check........................................Manifold Vacuum
Inspection
.............................
SPECIAL TOOLS....................................................
SPECIFICATIONS................................................General Specifications
....................................
Sealants
.......................................
.....................Service Specifications
....................................
TIMING BELT........................................................
TROUBLESHOOTING........................................44
31
11
15
14
11
13
16
16
84
4
84
26
10

II-2ENGINE - General Information
GENERAL INFORMATIONMllBAEC
SECTIONAL VIEW
I:
7EN0335ii
7EN0334
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ENGINE - General InformationII-3.UBRICATION SYSTEM
7LUOO25
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II-4ENGINE - Specifications
SPECIFICATIONSMllCA--GENERAL SPECIFICATIONS
‘,
‘dItems
Non-Turbo
Turbo
TypeV-type, DOHC
V-type, DOHC
Number of cylinders
6
6
Boremm (in.)
91 .I (3.587)
91 .I (3.587)
Stroke
mm (in.)
76.0 (2.992)
76.0 (2.992)
Piston displacementcc (win.)2,972 (181.4)
2,972 (181.4)
Compression ratio
10.08.0
Firing order
1-2-3-4-5-6
1-2-3-4-5-6
Valve timing
Intake valve
Opens (BTDC)16
16
Closes (ABDC)55”
55”
Exhaust valve
Opens (BBDC)4850”
Closes (ATDC)1517”SERVICE SPECIFICATIONS
MllCE -
Items
Compression pressure
kPa (psi)/rpm
Non-Turbo
Turbo
Compression pressure difference of all
cylinder
kPa (psi)
Manifold vacuum
mmHg (in.Hg.)
Non-Turbo
Turbo
Bas2Tig;ition timing at curb idle speedAct;ir-&yition
timing at curb idle speed
Curb idle speedrpmStandard value
-
-
-
520 (20)
495 (19)
5” f 2”
Approx. 15”700
ZII 100
Limit
min. 980
(139)/250 - 400
min. 810(115)/250-400
max. 100 (14)
d
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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.
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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)
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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)
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11-8ENGINE - Specifications / Special Tools
SEALANTS
MIKE- -
Items
Oil pan
Oil seal case
Oil pressure switch
Specified sealant
MITSUBISHI GENUINE Part No. MD9971
10 or equivalent
Oil pressure gauge unit
Rocker cover3M ATD Part No.8660 or equivalent
SPECIAL TOOLSMIlDA--
MD998051-01
Loosening and tightening of cylinder head bol
seal installer
compressor
Camshaft oilsealInstallation of camshaft oil seal
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ENGINE - Special ToolsII-9
Use withMD998765
Removal and installation of piston pinUse with MD998764
Supporting thecrancrankshaft bolt and
pulley areremoved
orreinstalled. Use together with MB990767-01
Tensioner pulley
socket wrenchAdjustment of timing belt
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II-IOENGINE - Troubleshooting
TROUBLESHOOTINGmiwm
SymptomProbable cause
RemedyI,aJ
Compression too low) Cylinder head gasket blown1 Replace gasketI
Piston ring worn or damage
Piston or cylinder worn
Replace rings
Repair or replace piston and/or cylinder
block
Valve seat worn or damage
Repair or replace valve and/or seat ring
3il pressure drop
Engine oil level too lowCheck engine oil level
Oil pressure switch faulty
Oil filter clogged
Replace oil pressure switch
Install new filter
Oil pump gears or cover worn
Thin or diluted engine oilReplace gears and/or cover
Change engine oil to correct viscosity
1 Oil relief valve stuck (opened)) Repair relief valve
Excessive bearing clearance
Replace bearingsIbOil relief valve stuck (closed)
Incorrect lash adjusterRepair relief valve
Replace lash adjuster Oil pressure too high
Noisy valves
Thin or diluted engine oil (low oil pressure)Change engine oil
Valve stem or valve guide worn or damageReplace valve and/or guide
Connecting rod noise/
nain bearing noiseInsufficient oil supplyCheck engine oil level
Thin or diluted engine oilChange engine oil
Excessive bearing clearanceReplace bearings
Timing belt noise
Incorrect belt tensionAdjust belt tension
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