EM-90
CYLINDER HEAD
Revision: 2006 November2007 350Z
If the engine speed is out of specified range, check battery liquid for proper gravity. Check engine
speed again with normal battery gravity.
If compression pressure is below minimum value, check valve clearances and parts associated with
combustion chamber (valve, valve seat, piston, piston ring, cylinder bore, cylinder head, cylinder head
gasket). After the checking, measure compression pressure again.
If some cylinders have low compression pressure, pour small amount of engine oil into the spark plug
hole of the cylinder to re-check it for compression.
–If the added engine oil improves the compression, piston rings may be worn out or damaged. Check the
piston rings and replace if necessary.
–If the compression pressure remains at low level despite the addition of engine oil, valves may be mal-
functioning. Check valves for damage. Replace valve or valve seat accordingly.
If two adjacent cylinders have respectively low compression pressure and their compression remains
low even after the addition of engine oil, cylinder head gaskets are leaking. In such a case, replace cyl-
inder head gaskets.
9. After inspection is completed, install removed parts.
10. Start engine, and make sure that engine runs smoothly.
11. Perform trouble diagnosis. If DTC appears, erase it. Refer to EC-81, "
TROUBLE DIAGNOSIS" .
Removal and InstallationNBS0000Z
Refer to GI-11, "Components" for symbol marks in the figure.
REMOVAL
1. Remove engine assembly from vehicle, and separate front suspension member and transmission from
engine. Refer to EM-101, "
ENGINE ASSEMBLY" .
2. Remove the following parts:
1. Engine rear lower slinger 2. Cylinder head (left bank) 3. Cylinder head bolt
4. Cylinder head (right bank) 5. Cylinder head gasket (right bank) 6. Cylinder head gasket (left bank)
7. Oil level gauge guide
A. Refer to EM-92
PBIC4985E
CYLINDER HEAD
EM-91
C
D
E
F
G
H
I
J
K
L
MA
EM
Revision: 2006 November2007 350Z
Fuel tube and fuel injector assembly: Refer to EM-34, "FUEL INJECTOR AND FUEL TUBE" .
Intake manifold: Refer to EM-20, "INTAKE MANIFOLD" .
Exhaust manifold: Refer to EM-22, "EXHAUST MANIFOLD AND THREE WAY CATALYST" .
Water inlet and thermostat assembly: Refer to CO-26, "WATER INLET AND THERMOSTAT ASSEM-
BLY" .
Water outlet and water pipe: Refer to CO-28, "WATER OUTLET AND WATER PIPING" .
Front and rear timing chain case: Refer to EM-53, "TIMING CHAIN" .
3. Remove camshaft (INT, EXH). Refer to EM-72, "
CAMSHAFT" .
4. Remove cylinder head bolts in reverse order as shown in the fig-
ure with cylinder head bolt wrench (commercial service tool).
5. Remove cylinder head gaskets.
INSPECTION AFTER REMOVAL
Cylinder Head Bolts Outer Diameter
Cylinder head bolts are tightened by plastic zone tightening
method. Whenever the size difference between “d1” and “d2”
exceeds the limit, replace them with new one.
If reduction of outer diameter appears in a position other than
“d2”, use it as “d2” point.
Cylinder Head Distortion
NOTE:
When performing this inspection, cylinder block distortion should be also checked. Refer to EM-128, "
CYLIN-
DER BLOCK DISTORTION" .
1. Using scraper, wipe off oil, scale, gasket, sealant and carbon deposits from surface of cylinder head.
CAUTION:
Do not allow gasket fragments to enter engine oil or engine coolant passages.
PBIC2057E
Limit (“d1” – “d2”) : 0.18 mm (0.0071 in)
PBIC2480E
EM-92
CYLINDER HEAD
Revision: 2006 November2007 350Z
2. At each of several locations on bottom surface of cylinder head,
measure the distortion in six directions.
If it exceeds the limit, replace cylinder head.
INSTALLATION
1. Install new cylinder head gaskets.
2. Turn crankshaft until No. 1 piston is set at TDC.
Crankshaft key should line up with the right bank cylinder cen-
ter line as shown in the figure.
3. Install cylinder head follow the steps below to tighten cylinder
head bolts in numerical order as shown in the figure.
CAUTION:
If cylinder head bolts re-used, check their outer diameters
before installation. Refer to EM-91, "
Cylinder Head Bolts
Outer Diameter" .
a. Apply new engine oil to threads and seat surfaces of cylinder
head bolts.
b. Tighten all cylinder head bolts.
c. Completely loosen all cylinder head bolts.
CAUTION:
In step “c”, loosen bolts in reverse order of that indicated in
the figure.
d. Tighten all cylinder head bolts.Limit : 0.1 mm (0.004 in)
SEM861E
1 : Crankshaft key
: Right bank side
PBIC5012E
: 105 N·m (11 kg-m, 77 ft-lb)
: 0 N·m (0 kg-m, 0 ft-lb)
: 39.2 N·m (4.0 kg-m, 29 ft-lb)
PBIC2057E
CYLINDER HEAD
EM-93
C
D
E
F
G
H
I
J
K
L
MA
EM
Revision: 2006 November2007 350Z
e. Turn all bolts 95 degrees clockwise (angle tightening).
CAUTION:
Check the tightening angle by using angle wrench (SST).
Avoid judgment by visual inspection without tool.
Check tightening angle indicated on angle wrench (SST) indi-
cator plate.
f. Turn all bolts 95 degrees clockwise again (angle tightening).
4. After installing cylinder head, measure distance between front
end faces of cylinder block and cylinder head (left and right
banks).
If the measured value is out of the standard, re-install cylinder
head.
5. Install in the reverse order of removal after this step.
INSPECTION AFTER INSTALLATION
Inspection for Leaks
The following are procedures for checking fluids leak, lubricates leak and exhaust gases leak.
Before starting engine, check oil/fluid levels including engine coolant and engine oil. If less than required
quantity, fill to the specified level. Refer to MA-11, "
RECOMMENDED FLUIDS AND LUBRICANTS" .
Use procedure below to check for fuel leakage.
–Turn ignition switch “ON” (with engine stopped). With fuel pressure applied to fuel piping, check for fuel
leakage at connection points.
–Start engine. With engine speed increased, check again for fuel leakage at connection points.
Run engine to check for unusual noise and vibration.
Warm up engine thoroughly to make sure there is no leakage of fuel, exhaust gases, or any oil/fluids
including engine oil and engine coolant.
Bleed air from lines and hoses of applicable lines, such as in cooling system.
After cooling down engine, again check oil/fluid levels including engine oil and engine coolant. Refill to the
specified level, if necessary.
Summary of the inspection items:
* Transmission/transaxle/CVT fluid, power steering fluid, brake fluid, etc.
PBIC0888E
Standard : 14.1 - 14.9 mm (0.555 - 0.587 in)
EMQ0662D
Items Before starting engine Engine running After engine stopped
Engine coolant Level Leakage Level
Engine oil Level Leakage Level
Other oils and fluid* Level Leakage Level
Fuel Leakage Leakage Leakage
Exhaust gases — Leakage —
EM-106
ENGINE ASSEMBLY
Revision: 2006 November2007 350Z
INSPECTION AFTER INSTALLATION
Inspection for Leaks
The following are procedures for checking fluids leak, lubricates leak and exhaust gases leak.
Before starting engine, check oil/fluid levels including engine coolant and engine oil. If less than required
quantity, fill to the specified level. Refer to MA-11, "
RECOMMENDED FLUIDS AND LUBRICANTS" .
Use procedure below to check for fuel leakage.
–Turn ignition switch “ON” (with engine stopped). With fuel pressure applied to fuel piping, check for fuel
leakage at connection points.
–Start engine. With engine speed increased, check again for fuel leakage at connection points.
Run engine to check for unusual noise and vibration.
Warm up engine thoroughly to make sure there is no leakage of fuel, exhaust gases, or any oil/fluids
including engine oil and engine coolant.
Bleed air from lines and hoses of applicable lines, such as in cooling system.
After cooling down engine, again check oil/fluid levels including engine oil and engine coolant. Refill to the
specified level, if necessary.
Summary of the inspection items:
* Transmission/transaxle/CVT fluid, power steering fluid, brake fluid, etc.Items Before starting engine Engine running After engine stopped
Engine coolant Level Leakage Level
Engine oil Level Leakage Level
Other oils and fluid* Level Leakage Level
Fuel Leakage Leakage Leakage
Exhaust gases — Leakage —
EM-108
CYLINDER BLOCK
Revision: 2006 November2007 350Z
DISASSEMBLY
1. Remove engine assembly from vehicle, and separate front suspension member and transmission from
engine. Refer to EM-101, "
ENGINE ASSEMBLY" .
2. Remove engine mounting brackets (RH and LH). Refer to EM-101, "
ENGINE ASSEMBLY" .
3. Remove the parts that may restrict installation of engine to widely use engine stand.
NOTE:
The procedure is described assuming that you use a widely use engine stand holding the surface, to
which transmission is installed.
Remove clutch cover and clutch disk (M/T models). Refer to CL-16, "CLUTCH DISC, CLUTCH
COVER" .
Remove flywheel (M/T models) or drive plate (A/T models). Fix crankshaft with a ring gear stopper
[SST: KV10118600 (J-48641)], and remove mounting bolts.
Loosen mounting bolts in diagonal order.
Check for deformation or damage (A).
CAUTION:
Do not disassemble drive plate.
Never place drive plate with signal plate facing down.
When handling signal plate, take care not to damage or
scratch it.
Handle signal plate in a manner that prevents it from
becoming magnetized.
4. Remove pilot bushing (M/T models) or pilot converter (A/T mod-
els) using pilot bushing puller [SST: ST16610001 (J-23907)] (A)
or suitable tool as necessary.
5. Lift the engine with hoist to install it onto the widely use engine stand.
A widely use engine stand can be used.
CAUTION:
Use engine stand that has a load capacity [approximately
220 kg (485 lb) or more] large enough for supporting the
engine weight.
NOTE:
This example is engine stand for holding at transmission
mounting side with flywheel (M/T models) or drive plate (A/T
models) removed.
6. Drain engine oil. Refer to LU-7, "
Changing Engine Oil" .
SEM760G
PBIC5015E
PBIC0085E
CYLINDER BLOCK
EM-109
C
D
E
F
G
H
I
J
K
L
MA
EM
Revision: 2006 November2007 350Z
7. Drain engine coolant by removing water drain plugs (1, 4) from
cylinder block both sides as shown in the figure.
8. Remove oil pan (upper, lower). Refer to EM-26, "
OIL PAN AND OIL STRAINER" .
9. Remove front timing chain case, timing chain and rear timing chain case. Refer to EM-53, "
TIMING
CHAIN" .
10. Remove cylinder head. Refer to EM-89, "
CYLINDER HEAD" .
11. Remove knock sensor.
CAUTION:
Carefully handle sensor avoiding shocks.
12. Remove rear oil seal.
13. Remove baffle plate from lower cylinder block.
14. Remove piston and connecting rod assembly as follows:
Before removing piston and connecting rod assembly, check the connecting rod side clearance. Refer
to EM-125, "
CONNECTING ROD SIDE CLEARANCE" .
a. Position crankshaft pin corresponding to connecting rod to be removed onto the bottom dead center.
b. Remove connecting rod bearing cap.
c. Using hammer handle or similar tool, push piston and connect-
ing rod assembly out to the cylinder head side.
CAUTION:
Be careful not to damage the cylinder wall and crankshaft
pin, resulting from an interference of the connecting rod big
end.
15. Remove connecting rod bearings from connecting rod and connecting rod bearing cap.
CAUTION:
Identify installation position, and store them without mixing them up.
16. Remove piston rings form piston.
Before removing piston rings, check the piston ring side clearance. Refer to EM-126, "PISTON RING
SIDE CLEARANCE" .
2 : Washer
3: Plug
: Engine front
PBIC5014E
PBIC2940E
CYLINDER BLOCK
EM-113
C
D
E
F
G
H
I
J
K
L
MA
EM
Revision: 2006 November2007 350Z
c. Install main bearings paying attention to the direction.
Main bearing with oil hole (B) and groove (C) goes on cylinder
block. The one without them goes on lower cylinder block.
Before installing main bearings, apply engine oil to the bear-
ing surface (inside). Do not apply engine oil to the back sur-
face, but thoroughly clean it.
When installing, align main bearing stopper protrusion to cut-
out of cylinder block and lower cylinder block.
Ensure the oil holes on cylinder block and those on the corresponding bearing are aligned.
5. Install crankshaft to cylinder block.
While turning crankshaft by hand, check that it turns smoothly.
6. Install lower cylinder block.
NOTE:
Lower cylinder block cannot be replaced as a single part, because it is machined together with cylinder
block.
Apply a continuous bead of liquid gasket with the tube presser [SST: WS39930000( — )] to lower
cylinder block as shown in the figure.
7. Inspect the outer diameter of lower cylinder block bolt. Refer to EM-133, "
LOWER CYLINDER BLOCK
BOLT OUTER DIAMETER" .
8. Install lower cylinder block bolts in numerical order as shown in the figure as follows:
a. Apply new engine oil to threads and seat surfaces of lower cylinder block bolts.
b. Tighten lower cylinder block bolt (No.17 to 26) in numerical order
as shown in the figure.
c. Repeat step b.
d. Tighten lower cylinder block bolts (No.1 to 16) in numerical order
as shown in the figure.
NOTE:
Use TORX socket (size E14) for bolts No.1 to 16.
A : Cylinder block side
D : Lower cylinder block side
: Engine front
PBIC5048E
a : 3.5 – 4.5 mm (0.138 – 0.177 in) dia
b: Apply to end
PBIC5017E
: 25.0 N·m (2.6 kg-m, 18 ft-lb)
: Engine front
: 35.3 N·m (3.6 kg-m, 26 ft-lb)
PBIC5016E