1991 MITSUBISHI 3000GT service

GENERAL - Maintenance Service00-39ogPOO268. ENGINE OIL FILTER (Change)
MOOEAEJThe quality of replacement filters varies considerably. Only high
quality filters should be used to assure most efficient service.
Genuine oil filters require that the filter be capable of
withstanding a pressure of 256 psi are high quality filters and
are recommended as follows:
Oil Filter Part No.
MITSUBISHI Genuine Parts: MD136790
ENGINE OIL FILTER SELECTIONThis vehicle is equipped with a full-flow, throw-away oil filter.
The same type of replacement filter is recommended as a
replacement filter for this vehicle. It is possible, particularly in
cold weather, that this vehicle may develop high oil pressure
for a short duration. You should be sure that any replacement
filter used on this vehicle is a high-quality filter and is capable of
withstanding a pressure of 256 psi (1,765
kpa) (manufacturer’s
specifications) to avoid filter and engine damage. The following
is a highquality filter and is strongly recommended for use on
this vehicle: Mitsubishi Engine Oil Filter P/N MD136790.
Any replacement oil filter should be installed in accordance with
the oil filter manufacturer’s installation instructions.
(1) Remove the engine oil filter by using the oil filter wrench.
(2) Clean the oil filter mounting surface of the oil filter bracket.
(3) Coat engine oil to the O-ring of new oil filter.
(4) Turn the oil filter by hand and install to the filter bracket.
NOTEThe oil filter tightening torque is 14 Nm (11
ft.lbs.1.(5) Start and run engine and check for engine oil leaks.
(6) After stopping engine, check oil level and refill as neces-
sary.
9. MANUAL TRANSAXLE (Inspect oil level)
MOOSBCGInspect each component for evidence of leakage, and check
the oil level by remaining the filler plug. If the oil is contami-
nated, it is necessary to replace it with new oil.
(1) With the vehicle parked at a level place, remove the filler
plug.
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00-40
GENERAL - Maintenance Service
(2) Check that the transaxle oil level is at the lower portion of
the filler plug hole. For AWD-vehicles, check that the
transfer oil level is at the portion shown in the illustration.
(3) Check to be sure that the transmission oil is not noticeably
‘ddirty, and that it has a suitable viscosity.
10. AUTOMATIC TRANSAXLE
(Inspect fluid level)
MOOSEDL
1.Drive until the fluid temperature reaches the usual tempera-
ture
[70 - 80°C (160 - 18O”F)I.2. Place vehicle on level floor.
3. Move selector lever sequentially to every position to fill
torque converter and hydraulic circuit with fluid, then place
lever in “N” Neutral position. This operation is necessary to
be sure that fluid level check is accurate.
4. Before removing dipstick, wipe all dirt from area around
dipstick. Then take out the dipstick and check the condition
of the fluid.
The transaxle should be overhauled under the following
conditions.
l If there is a “burning” odor.
l If the fluid color has become noticeably blacker.
lIf there is a noticeably great amount of metal particles in
the fluid.
5. Check to see if fluid level is in “HOT” range on dipstick. If
fluid level is low, add ATF until level reaches “HOT” range.
Low fluid level can cause a variety of conditions because it
allows pump to take in air along with fluid. Air trapped in
hydraulic circuit forms bubbles which make fluid spongy.
Therefore, pressures will be erratic.
Improper filling can also raise fluid level too high. When
transaxle has too much fluid, gears churn up foam and
cause same conditions which occur with low fluid level,
resulting in accelerated deterioration of ATF transmission
fluid.
In either case, air bubbles can cause overheating, fluid
oxidation, which can interfere with normal valve, clutch, and
servo operation. Foaming can also result in fluid escaping
from transaxle vent where it may be mistaken for a leak.
6. Be sure to examine fluid on dipstick closely.
L/(Change fluid)
Drain the fluid and check whether there is any evidence of
contamination.
Replenish with new fluid after the cause of any contamination
has been corrected.
(1) Remove drain plug at transaxle case bottom to let fluid
drain.(2) Place a drain container with large opening under the
transaxle oil pan.
(3) Loosen oil pan bolts and tap pan at one corner to break it
loose allowing fluid to drain, then remove oil pan.
d
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GENERAL - Maintenance Service00-41
Good
t-lVA0283
I04FOOOd(4) Check the oil filter for clogging and damage and replace if
necessary.
(5) Clean drain plug and tighten drain plug with gasket to 30
-35 Nm (22
- 25 ft.lbs.).
(6) Clean both gasket surfaces of transaxle case and oil pan.
(7) Install oil pan with new gasket and tighten oil pan bolts to
10 - 12 Nm (7.5 - 8.5 ft.lbs.).
(8) Pour 4.5 liters (4.8 qts.) of specified ATF into case through
dipstick hole. [Total quantity of ATF required is approx. 7.5
liters (7.9 qts.). Actually however, approx. 4.5 liters (4.8 qts.)
of fluid can be replaced because rest of fluid remains in
torque converter.]
Specified fluid: Dia ATF SP or MITSUBISHI PLUS ATF or
equivalent(9) Start engine and allow to idle for at least two minutes.
Then, with parking brake on, move selector lever momen-
tarily to each position, ending in “N” Neutral position.
(lO)Add sufficient ATF to bring fluid level to lower mark.
Recheck fluid level after transaxle is at normal operating
temperature. Fluid level should be between upper and
lower marks of “HOT” range. Insert dipstick fully to prevent
dirt from entering transaxle.
11. ENGINE COOLANT (Change)
MOOSBEHCheck the cooling system parts, such as radiator, heater, and
oil cooler hoses, thermostat and connections for leakage and
damage.
CHANGING COOLANT
1.
2.
3.
4.
5.
6.
7.
8.Remove te heat protectors (front and rear) from the exhaust
manifold.
Loosen the radiator drain plug, remove two drain plugs from
the engine block (one for each bank) and remove the
radiator cap to discharge coolant.
Remove the reservoir tank and discharge coolant.
When coolant has been discharged, pour water through the
filler port to flush coolant passage.
Coat the threads of the engine drain plugs with the
specified sealant and tighten the plugs to specification.
Specified sealant: 3M Nut Locking Part No. 4171 or
equivalentTightening torque: 40 Nm (29
ftlbs.)Fit the radiator drain plug securely.
Mount the reserve tank.
Slowly pour coolant into the radiator to the brim and also
into the reserve tank up to the FULL line.
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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.
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GENERAL - Maintenance Service00-43
15. DRIVE SHAFT BOOTS (Inspect for grease
leaks and damage)
MOOSBJD1. These components, which are permanently lubricated at
the factory, do not require periodic lubrication. Damaged
boots should be replaced to prevent leakage or contamina-
tion of the, grease.
2.Inspect the boots for proper sealing, leakage and damage.
Replace it if defective.
16. REAR AXLE (CONVENTIONAL DIFFEREN-
TIAL) (Inspect oil level)
- AWDMOOSBPDRemove the filler plug and inspect the oil level at bottom of filler
hole. If the oil level is slightly below the filler hole, it is in
satisfactory condition.
16. REAR AXLE (LIMITED-SLIP DIFFERENTIAL)
(Oil change)
- AWDMOOSBQEBefore changing the rear axle oil, check to make sure that there
is no oil leakage from the rear axle housing.
Remove the drain plug and drain out of the oil.
Put the oil plug
,back in place, and then pour new oil in through
the filler hole.
17. EXHAUST SYSTEM (CONNECTION PORTION
OF MUFFLER, PIPINGS AND CONVERTER
HEAT SHIELDS) (Check and service as re-
quired)
MOOSBLB1. Check for holes and gas leaks due to damage, corrosion,
etc.
2. Check the joints and connections for looseness and gas
leaks.3. Check the hanger rubber and brackets for damage.
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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-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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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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