2001 INFINITI QX4 service

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)
GI
MA
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
SERVICE DATA AND SPECIFICATIONS (SDS)
Camshaft and Camshaft Bearing (Cont'd)
EM-81

Main journal inner
diameter grade
(Without bearing)Grade No. A
Grade No. B
Grade No. C
Grade No. D
Grade No. E
Grade No. F
Grade No. G
Grade No. H
Grade No. J
Grade No. K
Grade No. L
Grade No. M
Grade No. N
Grade No. P
Grade No. R
Grade No. S
Grade No. T
Grade No. U
Grade No. V
Grade No. W
Grade No. X
Grade No. Y
Grade No. 4
Grade No. 763.993 - 63.994 (2.5194 - 2.5194)
63.994 - 63.995 (2.5194 - 2.5195)
63.995 - 63.996 (2.5195 - 2.5195)
63.996 - 63.997 (2.5195 - 2.5196)
63.997 - 63.998 (2.5196 - 2.5196)
63.998 - 63.999 (2.5196 - 2.5196)
63.999 - 64.000 (2.5196 - 2.5197)
64.000 - 64.001 (2.5197 - 2.5197)
64.001 - 64.002 (2.5197 - 2.5198)
64.002 - 64.003 (2.5198 - 2.5198)
64.003 - 64.004 (2.5198 - 2.5198)
64.004 - 64.005 (2.5198 - 2.5199)
64.005 - 64.006 (2.5199 - 2.5199)
64.006 - 64.007 (2.5199 - 2.5200)
64.007 - 64.008 (2.5200 - 2.5200)
64.008 - 64.009 (2.5200 - 2.5200)
64.009 - 64.010 (2.5200 - 2.5201)
64.010 - 64.011 (2.5201 - 2.5201)
64.011 - 64.012 (2.5201 - 2.5202)
64.012 - 64.013 (2.5202 - 2.5202)
64.013 - 64.014 (2.5202 - 2.5202)
64.014 - 64.015 (2.5202 - 2.5203)
64.015 - 64.016 (2.5203 - 2.5203)
64.016 - 64.017 (2.5203 - 2.5203)
Difference in inner
diameter between
cylindersStandardLess than 0.03 (0.0012)
Piston, Piston Ring and Piston PinNBEM0036AVAILABLE PISTONNBEM0036S01Unit: mm (in)
SEM882E
Piston skirt diameter ªAº StandardGrade No. 1 95.480 - 95.490 (3.7590 - 3.7594)
Grade No. 2 95.490 - 95.500 (3.7594 - 3.7598)
Grade No. 3 95.500 - 95.510 (3.7598 - 3.7602)
0.20 (0.0079) oversize (Service) 95.680 - 95.710 (3.7669 - 3.7681)
ªaº dimension41.0 (1.614)
Piston pin hole diameterGrade No. 0 21.993 - 21.999 (0.8659 - 0.8661)
Grade No. 1 21.999 - 22.005 (0.8661 - 0.8663)
Piston clearance to cylinder block 0.010 - 0.030 (0.0004 - 0.0012)
SERVICE DATA AND SPECIFICATIONS (SDS)
Cylinder Block (Cont'd)
EM-82

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
GI
MA
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
SERVICE DATA AND SPECIFICATIONS (SDS)
Piston, Piston Ring and Piston Pin (Cont'd)
EM-83

CrankshaftNBEM0038Unit: mm (in)
Main journal dia. ªDmº gradeGrade No. A
Grade No. B
Grade No. C
Grade No. D
Grade No. E
Grade No. F
Grade No. G
Grade No. H
Grade No. J
Grade No. K
Grade No. L
Grade No. M
Grade No. N
Grade No. P
Grade No. R
Grade No. S
Grade No. T
Grade No. U
Grade No. V
Grade No. W
Grade No. X
Grade No. Y
Grade No. 4
Grade No. 759.975 - 59.974 (2.3612 - 2.3612)
59.974 - 59.973 (2.3612 - 2.3611)
59.973 - 59.972 (2.3611 - 2.3611)
59.972 - 59.971 (2.3611 - 2.3611)
59.971 - 59.970 (2.3611 - 2.3610)
59.970 - 59.969 (2.3610 - 2.3610)
59.969 - 59.968 (2.3610 - 2.3609)
59.968 - 59.967 (2.3609 - 2.3609)
59.967 - 59.966 (2.3609 - 2.3609)
59.966 - 59.965 (2.3609 - 2.3608)
59.965 - 59.964 (2.3608 - 2.3608)
59.964 - 59.963 (2.3608 - 2.3607)
59.963 - 59.962 (2.3607 - 2.3607)
59.962 - 59.961 (2.3607 - 2.3607)
59.961 - 59.960 (2.3607 - 2.3606)
59.960 - 59.959 (2.3606 - 2.3606)
59.959 - 59.958 (2.3606 - 2.3605)
59.958 - 59.957 (2.3605 - 2.3605)
59.957 - 59.956 (2.3605 - 2.3605)
59.956 - 59.955 (2.3605 - 2.3604)
59.955 - 59.954 (2.3604 - 2.3604)
59.954 - 59.953 (2.3604 - 2.3603)
59.953 - 59.952 (2.3603 - 2.3603)
59.952 - 59.951 (2.3603 - 2.3603)
Pin journal dia. ªDpºGrade No. 0 51.968 - 51.974 (2.0460 - 2.0462)
Grade No. 1 51.962 - 51.968 (2.0457 - 2.0460)
Grade No. 2 51.956 - 51.962 (2.0445 - 2.0457)
Center distance ªrº40.36 - 40.44 (1.5890 - 1.5921)
Out-of-round (X þ Y) Standard Less than 0.002 (0.0001)
Taper (A þ B) Standard Less than 0.002 (0.0001)
Runout [TIR*] Limit Less than 0.10 (0.0039)
Free end playStandard 0.10 - 0.25 (0.0039 - 0.0098)
Limit 0.30 (0.0118)
SEM645EM715
*: Total indicator reading
SERVICE DATA AND SPECIFICATIONS (SDS)
Crankshaft
EM-84

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.
GI
MA
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
SERVICE DATA AND SPECIFICATIONS (SDS)
Available Main Bearing
EM-85

Available Connecting Rod BearingNBEM0040CONNECTING ROD BEARINGNBEM0040S01
Grade number Thickness ªTº mm (in) Identification color (mark)
0 1.500 - 1.503 (0.0591 - 0.0592) Black
1 1.503 - 1.506 (0.0592 - 0.0593) Brown
2 1.506 - 1.509 (0.0593 - 0.0594) Green
UNDERSIZENBEM0040S02Unit: mm (in)
Thickness Crank pin journal diameter ªDpº
0.25 (0.0098) 1.626 - 1.634 (0.0640 - 0.0643)Grind so that bearing clearance is the specified
value.
Miscellaneous ComponentsNBEM0041Unit: mm (in)
Drive plate runout [TIR]*Less than 0.15 (0.0059)
*: Total indicator reading
BEARING CLEARANCENBEM0041S01Unit: mm (in)
Main bearing clearanceStandard 0.035 - 0.045 (0.0014 - 0.0018)
Limit 0.065 (0.0026)
Connecting rod bearing clearanceStandard 0.034 - 0.059 (0.0013 - 0.0023)
Limit 0.070 (0.0028)
SERVICE DATA AND SPECIFICATIONS (SDS)
Available Connecting Rod Bearing
EM-86

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
GI
MA
EM
LC
EC
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX

Special Service ToolNBFE0001The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool nameDescription
KV10114400 (J38365)
Heated oxygen sensor
wrench
NT636
Loosening or tightening rear heated oxy-
gen sensor (For right bank)
a: 22 mm (0.87 in)
Commercial Service ToolsNBFE0007
Tool number
(Kent-Moore No.)
Tool nameDescription
Oxygen sensor thread
cleaner
(J-43897-18)
(J-43897-12)
NT778
Reconditioning the exhaust system
threads before installing a new oxygen
sensor. Use with anti-seize lubricant
shown below.
a: J-43897-18 (18 mm dia.) for Zirconia
Oxygen Sensor
b: J-43897-12 (12 mm dia.) for Titania
Oxygen Sensor
Anti-seize lubricant (Per-
matex
TM133AR or
equivalent meeting MIL
specification MIL-A-907)
NT779
Lubricating oxygen sensor thread cleaning
tool when reconditioning exhaust system
threads.
PREPARATION
Special Service Tool
FE-2