EM-124
CYLINDER BLOCK
Revision: 2006 November2007 350Z
Main Bearing Grade Table (All Journals)
Undersize Bearing Usage Guide
When the specified main bearing oil clearance is not obtained with standard size main bearings, use
underside (US) bearing.
When using undersize (US) bearing, measure the main bearing inner diameter with bearing installed, and
grind main journal so that the main bearing oil clearance satisfies the standard.
CAUTION:
In grinding crankshaft main journal to use undersize bear-
ings, keep the fillet R [1.5 – 1.7 mm (0.059 – 0.067 in)].
Bearing undersize table
Unit: mm (in) Grade numberThickness
Unit: mm (in)Width
Unit: mm (in)Identification color Remarks
0 2.500 - 2.503 (0.0984 - 0.0985)
19.9 - 20.1
(0.783 - 0.791)Black
Grade and color are
the same for upper
and lower bearings. 1 2.503 - 2.506 (0.0985 - 0.0987) Brown
2 2.506 - 2.509 (0.0987 - 0.0988) Green
3 2.509 - 2.512 (0.0988 - 0.0989) Yellow
4 2.512 - 2.515 (0.0989 - 0.0990) Blue
5 2.515 - 2.518 (0.0990 - 0.0991) Pink
6 2.518 - 2.521 (0.0991 - 0.0993) Purple
7 2.521 - 2.524 (0.0993 - 0.0994) White
01UPR 2.503 - 2.506 (0.0985 - 0.0987) Brown
Grade and color are
different for upper and
lower bearings. LWR 2.500 - 2.503 (0.0984 - 0.0985) Black
12UPR 2.506 - 2.509 (0.0987 - 0.0988) Green
LWR 2.503 - 2.506 (0.0985 - 0.0987) Brown
23UPR 2.509 - 2.512 (0.0988 - 0.0989) Yellow
LWR 2.506 - 2.509 (0.0987 - 0.0988) Green
34UPR 2.512 - 2.515 (0.0989 - 0.0990) Blue
LWR 2.509 - 2.512 (0.0988 - 0.0989) Yellow
45UPR 2.515 - 2.518 (0.0990 - 0.0991) Pink
LWR 2.512 - 2.515 (0.0989 - 0.0990) Blue
56UPR 2.518 - 2.521 (0.0991 - 0.0993) Purple
LWR 2.515 - 2.518 (0.0990 - 0.0991) Pink
67UPR 2.521 - 2.524 (0.0993 - 0.0994) White
LWR 2.518 - 2.521 (0.0991 - 0.0993) Purple
PBIC1908E
Size Thickness
US 0.25 (0.0098) 2.633 - 2.641 (0.1037 - 0.1040)
CYLINDER BLOCK
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Inspection After DisassemblyNBS00015
CRANKSHAFT END PLAY
Measure the clearance between thrust bearings and crankshaft
arm when crankshaft is moved fully forward or backward with
dial indicator.
If the measured value exceeds the limit, replace thrust bearings,
and measure again. If it still exceeds the limit, replace crank-
shaft also.
CONNECTING ROD SIDE CLEARANCE
Measure the side clearance between connecting rod and crank-
shaft arm with feeler gauge.
If the measured value exceeds the limit, replace connecting rod,
and measure again. If it still exceeds the limit, replace crank-
shaft also.
PISTON TO PISTON PIN OIL CLEARANCE
Piston Pin Hole Diameter
Measure the inner diameter of piston pin hole with inside microme-
ter.
Piston Pin Outer Diameter
Measure the outer diameter of piston pin with micrometer.
Piston to Piston Pin Oil Clearance
(Piston to piston pin oil clearance) = (Piston pin hole diameter) – (Piston pin outer diameter)
If the calculated value is out of the standard, replace piston and piston pin assembly.Standard : 0.10 - 0.25 mm (0.0040 - 0.0098 in)
Limit : 0.30 mm (0.0120 in)
PBIC2953E
Standard : 0.20 - 0.35 mm (0.0080 - 0.0138 in)
Limit : 0.40 mm (0.0160 in)
PBIC2954E
Standard : 21.993 - 22.005 mm (0.8659 - 0.8663 in)
PBIC0116E
Standard : 21.989 - 22.001 mm (0.8657 - 0.8662 in)
PBIC0117E
Standard : 0.002 - 0.006 mm (0.0001 - 0.0002 in)
EM-126
CYLINDER BLOCK
Revision: 2006 November2007 350Z
When replacing piston and piston pin assembly, refer to EM-119, "HOW TO SELECT PISTON" .
NOTE:
Piston is available together with piston pin as assembly.
Piston pin (piston pin hole) grade is provided only for the parts installed at the plant. For service parts,
no piston pin grades can be selected. (Only “0” grade is available.)
PISTON RING SIDE CLEARANCE
Measure the side clearance of piston ring and piston ring groove
with feeler gauge.
If the measured value exceeds the limit replace piston ring, and measure again. If it still exceeds the limit
replace piston also.
PISTON RING END GAP
Make sure that cylinder bore inner diameter is within the specifi-
cation. Refer to EM-129, "
Cylinder Bore Inner Diameter" .
Lubricate with new engine oil to piston and piston ring, and then
insert piston ring until middle of cylinder with piston, and mea-
sure the piston ring end gap with feeler gauge.
If the measured value exceeds the limit, replace piston ring, and measure again. If it still exceeds the limit,
re-bore cylinder and use oversize piston and piston rings.Standard:
Top ring : 0.040 - 0.080 mm (0.0016 - 0.0031 in)
2nd ring : 0.030 - 0.070 mm (0.0012 - 0.0028 in)
Oil ring : 0.055 - 0.155 mm (0.0022 - 0.0061 in)
Limit
Top ring : 0.11 mm (0.0043 in)
2nd ring : 0.10 mm (0.0040 in)
Oil ring : 0.19 mm (0.0075 in)
SEM024AA
Standard:
Top ring : 0.23 - 0.33 mm (0.0091 - 0.0130 in)
2nd ring : 0.33 - 0.48 mm (0.0130 - 0.0189 in)
Oil ring : 0.17 - 0.47 mm (0.0067 - 0.0185 in)
Limit:
Top ring : 0.42 mm (0.0165 in)
2nd ring : 0.57 mm (0.0224 in)
Oil ring : 0.63 mm (0.0248 in)
PBIC0118E
CYLINDER BLOCK
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CONNECTING ROD BEND AND TORSION
Check with connecting rod aligner.
If it exceeds the limit, replace connecting rod assembly.
CONNECTING ROD BIG END DIAMETER
Install connecting rod bearing cap without installing connecting
rod bearing, and tightening connecting rod bolts to the specified
torque. Refer to E M - 111 , "
ASSEMBLY" for the tightening proce-
dure.
Measure the inner diameter of connecting rod big end with
inside micrometer.
If out of the standard, replace connecting rod assembly.
CONNECTING ROD BUSHING OIL CLEARANCE
Connecting Rod Bushing Inner Diameter
Measure the inner diameter of connecting rod bushing with inside
micrometer.Bend:
Limit: 0.15 mm (0.0059 in) per 100 mm (3.94 in) length
To r s i o n :
Limit: 0.30 mm (0.0120 in) per 100 mm (3.94 in) length
PBIC2077E
Standard : 57.000 - 57.013 mm (2.2441 - 2.2446 in)
PBIC1641E
Standard : 22.000 - 22.012 mm (0.8661 - 0.8666 in)
PBIC0120E
EM-128
CYLINDER BLOCK
Revision: 2006 November2007 350Z
Piston Pin Outer Diameter
Measure the outer diameter of piston pin with micrometer.
Connecting Rod Bushing Oil Clearance
(Connecting rod bushing oil clearance) = (Connecting rod bushing inner diameter) – (Piston pin outer diame-
ter)
If the measured value exceeds the limit, replace connecting rod assembly and/or piston and piston pin
assembly.
If replacing piston and piston pin assembly, refer to EM-119, "HOW TO SELECT PISTON" .
If replacing connecting rod assembly, refer to EM-131, "CONNECTING ROD BEARING OIL CLEAR-
ANCE" to select the connecting rod bearing.
Factory installed parts grading:
Service parts apply only to grade “0”.
Unit: mm (in)
*: After installing in connecting rod
CYLINDER BLOCK DISTORTION
Using scraper, remove gasket on the cylinder block surface, and also remove engine oil, scale, carbon, or
other contamination.
CAUTION:
Be careful not to allow gasket flakes to enter engine oil or engine coolant passages.Standard : 21.989 - 22.001 mm (0.8657 - 0.8662 in)
PBIC0117E
Standard : 0.005 - 0.017 mm (0.0002 - 0.0007 in)
Limit : 0.030 mm (0.0012 in)
A : Sample code
B : Bearing stopper groove
C : Small end diameter grade
D : Big end diameter grade
E : Weight grade
F : Cylinder No.
G : Management code
H : Front mark
I : Management code
PBIC5046E
A : Piston grade number
B : Front mark
C : Piston pin grade number
Grade 0 1
Connecting rod bushing
inner diameter * 22.000 - 22 .0 06
(0.8661 - 0.8664) 22.006 - 22.012
(0.8664 - 0.8666)
Piston pin hole diameter 21.993 - 21.999
(0.8659 - 0.8661) 21.999 - 22. 005
(0.8661 - 0.8663)
Piston pin outer diameter 21.989 - 21.995
(0.8657- 0.8659) 21.995 - 22.001
(0.8659 - 0.8662)
PBIC4994E
EM-130
CYLINDER BLOCK
Revision: 2006 November2007 350Z
Piston Skirt Diameter
Measure the outer diameter of piston skirt with micrometer.
Piston to Cylinder Bore Clearance
Calculate by piston skirt diameter and cylinder bore inner diameter (direction “Y”, position “B”).
(Clearance) = (Cylinder bore inner diameter) – (Piston skirt diameter).
If calculated value exceeds the limit, replace piston and piston pin assembly. Refer to EM-119, "HOW TO
SELECT PISTON" .
Re-boring Cylinder Bore
1. Cylinder bore size is determined by adding piston to cylinder bore clearance to piston skirt diameter.
2. Install lower cylinder block, and tighten to the specified torque. Otherwise, cylinder bores may be distorted
in final assembly.
3. Cut cylinder bores.
NOTE:
When any cylinder needs boring, all other cylinders must also be bored.
Do not cut too much out of cylinder bore at a time. Cut only 0.05 mm (0.0020 in) or so in diameter at a
time.
4. Hone cylinders to obtain the specified piston to cylinder bore clearance.
5. Measure finished cylinder bore for the out-of-round and taper.
NOTE:
Measurement should be done after cylinder bore cools down.
CRANKSHAFT MAIN JOURNAL DIAMETER
Measure the outer diameter of crankshaft main journals with micrometer.
If out of the standard, measure the main bearing oil clearance. Then use undersize bearing. Refer to EM-
132, "MAIN BEARING OIL CLEARANCE" . Measure point
: Distance from the top 38.8 mm (1.528 in)
Standard
: 95.480 - 95.510 mm (3.7590 - 3.7602 in)
PBIC0125E
Standard : 0.010 - 0.030 mm (0.0004 - 0.0012 in)
Limit : 0.08 mm (0.0031 in)
Re-bored size calculation: D = A + B – C
where,
D: Bored diameter
A: Piston skirt diameter as measured
B: Piston to cylinder bore clearance (standard value)
C: Honing allowance 0.02 mm (0.0008 in)
Standard : 64.951 - 64.975 mm (2.5571 - 2.5581 in) dia.
CYLINDER BLOCK
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CRANKSHAFT PIN JOURNAL DIAMETER
Measure the outer diameter of crankshaft pin journal with
micrometer.
If out of the standard, measure the connecting rod bearing oil
clearance. Then use undersize bearing. Refer to EM-131,
"CONNECTING ROD BEARING OIL CLEARANCE" .
CRANKSHAFT OUT-OF-ROUND AND TAPER
Measure the dimensions at four different points as shown in the
figure on each main journal and pin journal with micrometer.
Out-of-round is indicated by the difference in the dimensions
between “X” and “Y” at “A” and “B”.
Taper is indicated by the difference in the dimensions between
“A” and “B” at “X” and “Y”.
If the measured value exceeds the limit, correct or replace crankshaft.
If corrected, measure the bearing oil clearance of the corrected main journal and/or pin journal. Then
select the main bearing and/or connecting rod bearing. Refer to EM-132, "
MAIN BEARING OIL CLEAR-
ANCE" and/or EM-131, "CONNECTING ROD BEARING OIL CLEARANCE" .
CRANKSHAFT RUNOUT
Place V-block on precise flat table, and support the journals on
the both end of crankshaft.
Place dial indicator straight up on the No. 3 journal.
While rotating crankshaft, read the movement of the pointer on
dial indicator. (Total indicator reading)
If it exceeds the limit, replace crankshaft.
CONNECTING ROD BEARING OIL CLEARANCE
Method by Calculation
Install connecting rod bearings to connecting rod and cap, and
tighten connecting rod bolts to the specified torque. Refer to
E M - 111 , "
ASSEMBLY" for the tightening procedure.
Measure the inner diameter of connecting rod bearing with
inside micrometer.
(Bearing oil clearance) = (Connecting rod bearing inner diameter) –
(Crankshaft pin journal diameter)Standard : 53.956 - 53.974 mm (2.1242 - 2.1250 in) dia.
PBIC0127E
Limit:
Out-of-round (Difference between “X” and “Y”)
: 0.0025 mm (0.0001 in)
Taper (Difference between “A” and “B”)
: 0.0025 mm (0.0001 in)
SBIA0535E
Standard : Less than 0.05 mm (0.0020 in)
Limit : 0.10 mm (0.004 in)
SEM346D
Standard : 0.040 - 0.053 mm (0.0016 - 0.0021 in)
(actual clearance)
Limit : 0.070 mm (0.0028 in)
PBIC1642E
EM-132
CYLINDER BLOCK
Revision: 2006 November2007 350Z
If the calculated value exceeds the limit, select proper connecting rod bearing according to connecting rod
big end diameter and crankshaft pin journal diameter to obtain the specified bearing oil clearance. Refer
to EM-120, "
HOW TO SELECT CONNECTING ROD BEARING" .
Method of Using Plastigage
Remove oil and dust on crankshaft pin journal and the surfaces of each bearing completely.
Cut plastigage slightly shorter than the bearing width, and place it in crankshaft axial direction, avoiding oil
holes.
Install connecting rod bearings to connecting rod and cap, and tighten connecting rod bolts to the speci-
fied torque. Refer to E M - 111 , "
ASSEMBLY" for the tightening procedure.
CAUTION:
Do not rotate crankshaft.
Remove connecting rod bearing cap and bearing, and using
scale on plastigage bag, measure the plastigage width.
NOTE:
The procedure when the measured value exceeds the limit is
same as that described in the “Method by Calculation”.
MAIN BEARING OIL CLEARANCE
Method by Calculation
Install main bearings (3) to cylinder block (1) and lower cylinder
block (2), and tighten lower cylinder block bolts to the specified
torque. Refer to EM-111, "
ASSEMBLY" for the tightening proce-
dure.
Measure the inner diameter of main bearing with bore gauge.
(Bearing clearance) = (Main bearing inner diameter) – (Crankshaft
main journal diameter)
If the clearance exceeds the limit, select proper main bearing according to main bearing inner diameter
and crankshaft main journal diameter to obtain the specified bearing oil clearance. Refer to EM-122,
"HOW TO SELECT MAIN BEARING" .
Method of Using Plastigage
Remove oil and dust on crankshaft main journal and the surfaces of each bearing completely.
Cut plastigage slightly shorter than the bearing width, and place it in crankshaft axial direction, avoiding oil
holes.
Install main bearings to cylinder block and lower cylinder block, and tighten lower cylinder block bolts with
lower cylinder block to the specified torque. Refer to E M - 111 , "
ASSEMBLY" for the tightening procedure.
CAUTION:
Do not rotate crankshaft.
PBIC1149E
Standard : 0.035 - 0.045 mm (0.0014 - 0.0018 in)
(actual clearance)
Limit : 0.065 mm (0.0026 in)
PBIC5126J