CYLINDER HEADEM-75
< REMOVAL AND INSTALLATION > [QR25DE]
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• Replace the cylinder heads bolts with new ones if the size differ-
ence between d1 and d2 exceeds the limit.
• If reduction of outer diameter appears in a position other than d2, use it as d2 point.
INSTALLATION
1. Clean surfaces of cylinder head and cylinder block.
2. Install a new cylinder head gasket. CAUTION:
Do not reuse cylinder head gasket.
3. Install the cylinder head.
4. Follow the steps below to tighten the cylinder head bolts in the numerical order as shown. • Clean threads and seating surfaces of bolts.
• Apply new engine oil to the threads and the seating surfaces of bolts.
CAUTION:
• If cylinder head bolts are re-used, check their ou ter diameters before installation. Follow the
Outer Diameter of Cylinder H ead Bolts measurement procedure.
• Check and confirm the tighte ning angle by using angle
wrench or protractor. Do not judge angle by visual inspec-
tion.
5. Installation of the remaining components is in the reverse order of removal. Limit (d1 - d2) : 0.23 mm (0.0091 in) or more
KBIA0189E
Tool number (A) : KV10112100 (BT-8653-A)
PBIC3208J
Step a : 50 N·m (5.1 kg-m, 37 ft-lb) in order
Step b : 60 ° clockwise in order
Step b : Loosen to 0 N·m in order
Step c : 39.2 N·m (4.0 kg-m, 29 ft-lb) in order
Step d : 75 ° clockwise in order
Step e : 75 ° clockwise in order
: Engine frontAWBIA1325GB
Revision: November 20132014 Altima NAM
EM-78
< REMOVAL AND INSTALLATION >[QR25DE]
CYLINDER HEAD
4. Install new valve oil seal using Tool (A) as shown.
5. Install valve. • Install larger diameter to intake side.
6. Install valve spring with valve spring seat (1). • Install valve spring so that the identification color faces upward
(A).
• Install smaller pitch to cylinder head side (B).
• Confirm the identification color of the valve spring.
• Intake: white
• Exhaust: light blue
7. Install valve spring retainer.
8. Install valve collet. • Compress valve spring using Tools. Install valve collet with amagnet hand.
CAUTION:
When working take care not to damage valve lifter holes.
• Tap valve stem edge lightly with a plastic hammer after instal-
lation to check its installed condition.
9. Install valve lifter.
10. Install spark plug tube.
a. Remove old liquid gasket from cylinder head mounting hole.
b. Apply liquid gasket all around on spark plug tube with a 12 mm (0.47 in) width from edge of spark plug tube on the press fit side.
• Use Three Bond or equivalent. Refer to GI-21, "Recom-
mended Chemical Products and Sealants".
c. Press fit spark plug tube so that height (H) is as shown.
CAUTION:
• When press fitting be careful not to deform spark plug
tube.
• After press fitting, wipe off any protruding liquid gasket on top surface of cylinder head.
Inspection After DisassemblyINFOID:0000000009460506
CYLINDER HEAD DISTORTION
Oil seal installed height (H) : 12.1 mm (0.476 in)
Tool number : KV10115600 (J-38958)
ALBIA0864GB
JPBIA4479ZZ
Tool number (A) : KV10116200 (J-26336-A)
Tool number (B) : KV10109220 ( — )
Tool number (C) : KV10115900 (J-26336-20)
JPBIA1365ZZ
Press fit height (H) standard value : 41.7 mm (1.642 in)
ALBIA0870GB
Revision: November 20132014 Altima NAM
CYLINDER HEADEM-79
< REMOVAL AND INSTALLATION > [QR25DE]
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1. Wipe off oil and remove water scale deposits, old gasket, old
sealer, and carbon with a scraper.
CAUTION:
Use care not to allow gasket debris to enter passages for oil
or water.
2. At each of several locations on bottom surface of cylinder head, measure distortion in six directi ons using suitable tools (A, B).
• If measurements exceed the limit, replace cylinder head.
VALVE DIMENSIONS
Check dimensions of each valve. Refer to EM-111, "Standard and Limit".
VALVE GUIDE CLEARANCE
• Measure diameter of valve stem using suitable tool (A) as shown.
• Measure inner diameter of valve guide with a bore gauge as shown.
• Valve guide clearance = (Valve guide inner diameter) - (Valve stem diameter)
• If it exceeds the limit, replace valve guide and/or va lve. When valve guide must be replaced, follow the
"VALVE GUIDE REPLACEMENT" procedure.
VALVE GUIDE REPLACEMENT
When valve guide is removed, replace with oversized (0.2 mm, 0.008 in) valve guide.
1. To remove valve guide, heat cylinder head to 110 ° to 130 °C
(230 ° to 266 °F) by soaking in heated oil.
WARNING:
Cylinder head contains heat. Wh en working, wear protective
equipment to avoid getting burned. Limit : 0.1 mm (0.004 in)
PBIC3207J
Standard
Intake : 5.965 - 5.980 mm (0.2348 - 0.2354 in)
Exhaust : 5.955 - 5.970 mm (0.2344 - 0.2350 in)
Standard
Intake and
Exhaust : 6.000 - 6.018 mm (0.2362 - 0.2369 in)
Valve guide clearance
Standard
Intake : 0.020 - 0.053 mm (0.0008 - 0.0021 in)
Exhaust : 0.030 - 0.063 mm (0.0012 - 0.0025 in)
Limit
Intake : 0.08 mm (0.003 in)
Exhaust : 0.09 mm (0.004 in)
AWBIA0068ZZ
SEM008A
Revision: November 20132014 Altima NAM
CYLINDER HEADEM-81
< REMOVAL AND INSTALLATION > [QR25DE]
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After confirming that the dimensions of valve guides and valves are
within specifications, perform this procedure:
• Apply prussian blue (or white lead) onto contacting surface of valve
seat to check the condition of t he valve contact on the seat sur-
face.
• Check if the contact area band is continuous all around the circum-
ference.
• If not, grind to adjust valve fitti ng and check again. If the contacting
surface still has NG conditions even after the re-check, replace the
valve seat.
VALVE SEAT REPLACEMENT
NOTE:
When valve seat is removed, replace with an oversized [0.5 mm (0.020 in)] valve seat.
1. Bore out old seat until it collapses. Boring shoul d not continue beyond the bottom face of the seat recess
in the cylinder head. Set the machine depth stop to ensure this.
2. Ream cylinder head recess diameter for service valve seat.
• Be sure to ream in circles concentric to the valve guide center.This will enable the valve seat to fit correctly.
3. Heat cylinder head to 110 ° to 130 °C (230 ° to 266 °F) by soaking
in heated oil.
WARNING:
Cylinder head contains heat . When working, wear protec-
tive equipment to avo id getting burned.
4. Use valve seats cooled well with dry ice. Force fit valve seat into cylinder head. CAUTION:
Avoid directly touching the cold valve seats.
5. Finish the seat to the specified dimensions using suitable tool. Refer to EM-111, "Standard and Limit"
.
CAUTION:
When using valve seat cutter, firmly grip the cutter handle
with both hands. Then, press on the contacting surface all
around the circumference to cu t in a single drive. Improper
pressure on the cutter or cutting many different times may
result in a defective valve seat.
6. Using compound, grind to adjust valve fitting.
7. Check again for normal contact.
SBIA0322E
Intake : 37.000 - 37.016 mm (1.4567 - 1.4573 in)
Exhaust : 32.000 - 32.016 mm (1.2598 - 1.2605 in)
SEM795A
SEM008A
SEM934C
Revision: November 20132014 Altima NAM
ENGINE ASSEMBLYEM-85
< UNIT REMOVAL AND INSTALLATION > [QR25DE]
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27. Remove the LH and RH drive shafts. Refer to
FAX-10, "Removal and Installation (LH)", FAX-12, "Removal
and Installation (RH)".
28. Remove the drive belt. Refer to EM-19, "Removal and Installation"
.
29. Remove the front suspension member. Refer to FSU-20, "Removal and Installation"
.
30. Remove the A/C compressor with piping connected and support using suitable wire.
31. Disconnect the transaxle shift controls. Refer to TM-407, "Removal and Installation"
.
32. Install engine slingers into the rear of the cylinder head (A) and front engine mounting bracket holes (B).
• Use engine mounting bolt holes for front slinger.
• Use the holes in the rear of the cylinder head for the rear
slinger.
33. Support engine and transaxle assembly with engine lifti ng equipment from the top with the vehicle raised
on a hoist.
34. Remove the RH engine mount torque rod, RH engine support bracket and RH engine mounting insulator and bracket.
35. Remove LH transaxle mounting insulator through-bolts.
36. Lower the engine and transaxle assembly from the engine compartment using suitable tool.
CAUTION:
• Before and during this procedure, alw ays check if any harnesses are left connected.
• Avoid any damage to, or any oil/grease smearing or spills onto the engine mounting insulators.
37. Remove the starter motor. Refer to STR-22, "QR25DE : Removal and Installation"
.
38. Remove engine and transaxle harness.
39. Separate engine and transaxle. Refer to TM-206, "Exploded View"
.
INSTALLATION
Installation is in the reverse order of removal.
NOTE:
Tighten the transmission bolts to specification. Refer to TM-407, "Removal and Installation"
.
• Do not allow oil to get on mounting insulators. Be careful not to damage mounting insulators.
• If parts have a direction mark (arrow) this indicates front of the vehicle, and the parts must be installed
according to the identification mark.
• Install the RH engine mounting bracket bolts in the following steps:
- First install bolts (A) and (B) loosely.
- Install and tighten the five RH engine mounting bracket bolts to specification in the order as shown.
- : Front
INSPECTION AFTER INSTALLATION
• Before starting engine, check oil/fluid levels incl uding engine coolant and engine oil. If less than required
quantity, fill to the specified level. Refer to MA-11, "FOR USA AND CANADA : 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 leak- age 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. Slinger bolts (A) : 28 N·m (2.8 kg-m, 21 ft-lb)
Slinger bolts (B) : 48 N·m (4.9 kg-m, 35 ft-lb))
AWBIA1363ZZ
RH engine mounting bracket bolt : 48.2 N·m (4.9 kg-m, 36 ft-lb)
ALBIA0541ZZ
Revision: November 20132014 Altima NAM
EM-86
< UNIT REMOVAL AND INSTALLATION >[QR25DE]
ENGINE ASSEMBLY
NOTE:
If hydraulic pressure inside timing chain tensioner drops after removal and installation, slack in the guide
may generate a pounding noise during and just after engine start. However, this is normal. Noise will stop
after hydraulic pressure rises.
• Warm up engine thoroughly to make sure there is no leakage of fuel, exhaust gas, or any oils/fluids including engine oil and engine coolant.
• Bleed air from passages in lines and hoses, such as in cooling system.
• After cooling down engine, again check oil/fluid levels including engine oil and engine coolant. Refill to spec- ified level, if necessary.
• Summary of the inspection items:
*Power steering fluid, brake fluid, etc. Item Before starting engine Engine running After engine stopped
Engine coolant Level Leakage Level
Engine oil Level Leakage Level
Transmission/
transaxle fluid CVT Models
Leakage Level/Leakage Leakage
Other oils and fluids* Level Leakage Level
Fuel Leakage Leakage Leakage
Exhaust gas — Leakage —
Revision: November 20132014 Altima NAM
EM-88
< UNIT DISASSEMBLY AND ASSEMBLY >[QR25DE]
CYLINDER BLOCK
Disassembly and Assembly
INFOID:0000000009460510
CAUTION:
Apply new engine oil to parts marked in illustration before installation.
NOTE:
The following procedures explain how to disassem ble the engine with the engine stand fastened to the bell
housing. Some steps may be different if using a different type of engine stand.
DISASSEMBLY
1. Remove the engine and transaxle as an assembly from the vehicle, and separate the transaxle from the
engine. Refer to EM-84, "Removal and Installation"
.
2. Remove the drive plate. Hold the crankshaft using Tool (A) and use a suitable tool to remove the bolts.
3. Remove pilot converter using Tool.
4. Remove the rear oil seal. Refer to EM-72, "Removal and Installation of Rear Oil Seal"
.
5. Mount the engine on a suitable engine stand (A). CAUTION:
• Use an engine stand that has a load capacity large
enough for supporting the engine weight [approximately
135 kg (298 lb) or more].
• Before removing the hanging chains, check the engine
stand is stable and there is no risk of overturning.
NOTE:
The figure shows an example of widely used engine stand (A)
that can support mating surface of transaxle with drive plate
removed.
• Remove the following parts if the engine stand load capacity is not adequate, to reduce the potential risk of overturning stand:
- Intake manifold. Refer to EM-30, "Removal and Installation"
.
- Exhaust manifold. Refer to EM-33, "Removal and Installation"
.
- Rocker cover. Refer to EM-45, "Removal and Installation"
.
6. Drain any remaining engine oil and coolant from the engine.
7. Remove the exhaust manifold and three way catalyst assembly. Refer to EM-33, "Removal and Installa-
tion".
8. Remove the intake manifold and fuel tube assembly. Refer to EM-30, "Removal and Installation"
.
28. Oil level gauge guide 29. Oil level gauge 30. O-ring
A. Follow assembly procedure
Tool Number : KV11105210 (J-44716)
PBIC3226J
Tool Number : ST16610001 (J-23907)
WBIA0483E
PBIC3227J
Revision: November 20132014 Altima NAM
CYLINDER BLOCKEM-89
< UNIT DISASSEMBLY AND ASSEMBLY > [QR25DE]
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9. Remove the ignition coils. Refer to
EM-40, "Removal and Installation".
10. Remove the rocker cover. Refer to EM-45, "Removal and Installation"
.
11. Remove the front cover, timing chain, and balancer unit. Refer to EM-62, "Removal and Installation"
.
12. Remove the cylinder head. Refer to EM-74, "Removal and Installation"
.
13. Remove oil cooler. Refer to LU-16, "Exploded View"
.
14. Remove the knock sensor. CAUTION:
Carefully handle the sensor and do not drop the sensor.
15. Remove crankshaft position sensor (POS) (2) and O-ring (1).
CAUTION:
• Avoid impacts such as a dropping.
• Do not disassemble.
• Keep it away from metal particles.
• Do not place sensor close to magnetic materials.
• Do not reuse O-ring.
16. Remove the piston and connecting rod assemblies.
a. Position the crankshaft and corresponding connecting rod, to be removed, to the bottom dead center stroke.
b. Remove the connecting rod cap. Number the cap so it can be assembled in the same position.
c. Using a hammer handle or similar tool, push the piston and con- necting rod assembly out of the top of the cylinder block. Num-
ber the piston and rod so it can be assembled in the same
position.
• Before removing the piston and connecting rod assembly,
check the connecting rod side clearance. Refer to EM-96,
"Inspection After Disassembly".
17. Remove the connecting rod bearings. If reusing, num ber them so they can be assembled in the same
position and direction.
CAUTION:
• When removing them, note the installation position. Keep them in the correct order.
18. Remove the piston rings from the piston. • Use a piston ring expander.
• Before removing the piston rings, check the piston ring side
clearance. Refer to EM-96, "Inspection After Disassembly"
.
CAUTION:
• When removing the piston rings, be careful not to damage
the piston.
• Be careful not to damage piston rings by expanding them excessively, if reusing them.
: Engine front
AWBIA1332GB
PBIC0259E
PBIC0087E
Revision: November 20132014 Altima NAM