2001 INFINITI QX4 IDX

General SpecificationsNBEM0029
Cylinder arrangementV- 6
Displacement cm
3(cu in)3,498 (213.45)
Bore and stroke mm (in)95.5 x 81.4 (3.760 x 3.205)
Valve arrangementDOHC
Firing order1-2-3-4-5-6
Number of piston ringsCompression 2
Oil 1
Number of main bearings4
Compression ratio10.0
Compression PressureNBEM0030Unit: kPa (kg/cm2, psi)/300 rpm
Compression pressureStandard 1,275 (13.0, 185)
Minimum 981 (10.0, 142)
Differential limit between cylinders 98 (1.0, 14)
Cylinder number
SEM713A
Cylinder HeadNBEM0031Unit: mm (in)
Standard Limit
Head surface distortion Less than 0.03 (0.0012) 0.1 (0.004)
SEM949E
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SERVICE DATA AND SPECIFICATIONS (SDS)
General Specifications
EM-75

Thickness mm (in) Identification mark
2.42 (0.0953) 242
2.43 (0.0957) 243
2.44 (0.0961) 244
2.45 (0.0965) 245
2.46 (0.0969) 246
2.47 (0.0972) 247
2.48 (0.0976) 248
2.49 (0.0980) 249
2.50 (0.0984) 250
2.51 (0.0988) 251
2.52 (0.0992) 252
2.53 (0.0996) 253
2.54 (0.1000) 254
2.55 (0.1004) 255
2.56 (0.1008) 256
2.57 (0.1012) 257
2.58 (0.1016) 258
2.59 (0.1020) 259
2.60 (0.1024) 260
2.61 (0.1028) 261
2.62 (0.1031) 262
2.63 (0.1035) 263
2.64 (0.1039) 264
2.65 (0.1043) 265
2.66 (0.1047) 266
2.67 (0.1051) 267
2.68 (0.1055) 268
2.69 (0.1059) 269
2.70 (0.1063) 270
2.71 (0.1067) 271
2.72 (0.1071) 272
2.73 (0.1075) 273
2.74 (0.1079) 274
2.75 (0.1083) 275
2.76 (0.1087) 276
2.77 (0.1091) 277
2.78 (0.1094) 278
2.79 (0.1098) 279
2.80 (0.1102) 280
2.81 (0.1106) 281
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SERVICE DATA AND SPECIFICATIONS (SDS)
Valve (Cont'd)
EM-77

VALVE GUIDENBEM0032S06Unit: mm (in)
SEM950E
Standard Service
Valve guide Outer diameter 10.023 - 10.034 (0.3946 - 0.3950) 10.223 - 10.234 (0.4025 - 0.4029)
Valve guide Inner diameter (Finished size) 6.000 - 6.018 (0.2362 - 0.2369)
Cylinder head valve guide hole diameter 9.975 - 9.996 (0.3927 - 0.3935) 10.175 - 10.196 (0.4006 - 0.4014)
Interference fit of valve guide 0.027 - 0.059 (0.0011 - 0.0023)
Standard Max. tolerance
Stem to guide clearanceIntake 0.020 - 0.053 (0.0008 - 0.0021) 0.08 (0.0031)
Exhaust 0.040 - 0.073 (0.0016 - 0.0029) 0.1 (0.004)
Valve deflection limitIntake Ð 0.24 (0.0094)
Exhaust Ð 0.28 (0.0110)
Projection length ªLº12.6 - 12.8 (0.496 - 0.504)
Valve SeatNBEM0033Unit: mm (in)
SEM021EB
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SERVICE DATA AND SPECIFICATIONS (SDS)
Valve (Cont'd)
EM-79

EM671
Cam height ªAº Intake and exhaust 44.465 - 44.655 (1.7506 - 1.7581)
Wear limit of cam height 0.2 (0.008)
Valve timing
Unit: degree
abcde f
232 230 ±3 53 6 46
Cylinder BlockNBEM0035Unit: mm (in)
SEM022EA
Surface flatnessStandardLess than 0.03 (0.0012)
Limit0.10 (0.0039)
Cylinder bore Inner diameterStandardGrade No. 1 95.500 - 95.510 (3.7598 - 3.7602)
Grade No. 2 95.510 - 95.520 (3.7602 - 3.7606)
Grade No. 3 95.520 - 95.530 (3.7606 - 3.7610)
Wear limit 0.20 (0.0079)
Out-of-round (X þ Y)Less than 0.015 (0.0006)
Taper (AþBþC)Less than 0.015 (0.0006)
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SERVICE DATA AND SPECIFICATIONS (SDS)
Camshaft and Camshaft Bearing (Cont'd)
EM-81

PISTON RING=NBEM0036S02Unit: mm (in)
Standard Limit
Side clearanceTop 0.040 - 0.080 (0.0016 - 0.0031) 0.11 (0.0043)
2nd 0.030 - 0.070 (0.0012 - 0.0028) 0.1 (0.004)
Oil ring 0.015 - 0.050 (0.0006 - 0.0020) Ð
End gapTop 0.23 - 0.33 (0.0091 - 0.0130) 0.54 (0.0213)
2nd 0.33 - 0.48 (0.0130 - 0.0189) 0.80 (0.0315)
Oil (rail ring) 0.20 - 0.80 (0.0079 - 0.0315) 0.95 (0.0374)
PISTON PINNBEM0036S03Unit: mm (in)
Piston pin outer diameterGrade No. 0 21.989 - 21.995 (0.8657 - 0.8659)
Grade No. 1 21.995 - 22.001 (0.8659 - 0.8662)
Interference fit of piston pin to piston 0.002 - 0.006 (0.0001 - 0.0002)
Piston pin to connecting rod bushing clearanceStandard 0.005 - 0.017 (0.0002 - 0.0007)
Limit 0.030 (0.0012)
*: Values measured at ambient temperature of 20ÉC (68ÉF)
Connecting RodNBEM0037Unit: mm (in)
Center distance144.15 - 144.25 (5.6752 - 5.6791)
Bend [per 100 (3.94)] Limit 0.15 (0.0059)
Torsion [per 100 (3.94)] Limit 0.30 (0.0118)
Connecting rod small end inner diameter 23.980 - 24.000 (0.9441 - 0.9449)
Piston pin bushing inner diameter*Grade No. 0 22.000 - 22.006 (0.8661 - 0.8664)
Grade No. 1 22.006 - 22.012 (0.8664 - 0.8666)
Connecting rod big end inner diameter 55.000 - 55.013 (2.1654 - 2.1659)
Side clearanceStandard 0.20 - 0.35 (0.0079 - 0.0138)
Limit 0.40 (0.0157)
*: After installing in connecting rod
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SERVICE DATA AND SPECIFICATIONS (SDS)
Piston, Piston Ring and Piston Pin (Cont'd)
EM-83

Available Main BearingNBEM0039
SEM175F
Grade number Thickness ªTº mm (in)Width ªWº
mm (in)Identification color
(UPR/LWR)Remarks
0 2.000 - 2.003 (0.0787 - 0.0789)
19.9 - 20.1
(0.783 - 0.791)Black
Grade is the same for
upper and lower bearings. 1 2.003 - 2.006 (0.0789 - 0.0790) Brown
2 2.006 - 2.009 (0.0790 - 0.0791) Green
3 2.009 - 2.012 (0.0791 - 0.0792) Yellow
4 2.012 - 2.015 (0.0792 - 0.0793) Blue
5 2.015 - 2.018 (0.0793 - 0.0794) Pink
6 2.018 - 2.021 (0.0794 - 0.0796) Purple
7 2.021 - 2.024 (0.0796 - 0.0797) White
01UPP 2.003 - 2.006 (0.0789 - 0.0790)
Brown/Black
Grade is different for upper
and lower bearings. LWR 2.000 - 2.003 (0.0787 - 0.0789)
12UPR 2.006 - 2.009 (0.0790 - 0.0791)
Green/Brown
LWR 2.003 - 2.006 (0.0789 - 0.0790)
23UPR 2.009 - 2.012 (0.0791 - 0.0792)
Yellow/Green
LWR 2.006 - 2.009 (0.0790 - 0.0791)
34UPR 2.012 - 2.015 (0.0792 - 0.0793)
Blue/Yellow
LWR 2.009 - 2.012 (0.0791 - 0.0792)
45UPR 2.015 - 2.018 (0.0793 - 0.0794)
Pink/Blue
LWR 2.012 - 2.015 (0.0792 - 0.0793)
56UPR 2.018 - 2.021 (0.0794 - 0.0796)
Purple/Pink
LWR 2.015 - 2.018 (0.0793 - 0.0794)
67UPR 2.021 - 2.024 (0.0796 - 0.0797)
White/Purple
LWR 2.018 - 2.021 (0.0794 - 0.0796)
UNDERSIZENBEM0039S01Unit: mm (in)
Thickness Main journal diameter ªDmº
0.25 (0.0098) 2.132 - 2.140 (0.0839 - 0.0843)Grind so that bearing clearance is the specified
value.
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SERVICE DATA AND SPECIFICATIONS (SDS)
Available Main Bearing
EM-85

ACCELERATOR CONTROL, FUEL &
EXHAUST SYSTEMS
SECTION
FE
CONTENTS
PREPARATION...............................................................2
Special Service Tool ....................................................2
Commercial Service Tools ...........................................2
ACCELERATOR CONTROL SYSTEM...........................3
Removal and Installation .............................................3
Adjusting Accelerator Wire ..........................................3FUEL SYSTEM................................................................4
Removal and Installation .............................................4
FUEL TANK...............................................................5
FUEL PUMP AND GAUGE.........................................6
EXHAUST SYSTEM........................................................8
Removal and Installation .............................................8
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Removal and InstallationNBFE0002CAUTION:
IWhen removing accelerator wire, make a mark to indicate lock nut's initial position.
ICheck that throttle valve opens fully when accelerator pedal is fully depressed. Also check that it
returns to idle position when pedal is released.
ICheck accelerator control parts for improper contact with any adjacent parts.
IWhen connecting accelerator wire, be careful not to twist or scratch its inner wire.
IRefer to EL-240, ªAUTOMATIC SPEED CONTROL DEVICEº for ASCD wire adjustment.
SFE635A
SEF793W
SFE249AE
Adjusting Accelerator WireNBFE00031. Remove the vacuum hose connected to the throttle opener.
2. Connect suitable vacuum hose to vacuum pump as shown left.
3. Apply vacuum [more than þ40.0 kPa (þ300 mmHg, þ11.81
inHg)] until the throttle drum becomes free from the rod of the
throttle opener.
Make sure that there is clearance between the throttle
drum and rod.
If NG, refer to EC-101, ªBasic Inspectionº.
If OK, go to following step.
4. Loosen lock nut.
5. Tighten accelerator adjusting nut until throttle drum starts to
move.
6. From that position, turn back adjusting nut 1.5 to 2 turns, and
secure lock nut.
7. Release vacuum from the throttle opener.
8. Remove vacuum pump and vacuum hose from the throttle
opener.
9. Reinstall the original vacuum hose to the throttle opener
securely.
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ACCELERATOR CONTROL SYSTEM
Removal and Installation
FE-3