2011 INFINITI QX56 oil pump

EM-16
< BASIC INSPECTION >
COMPRESSION PRESSURE
COMPRESSION PRESSURE
InspectionINFOID:0000000006289521
1. Warm up engine thoroughly. Then, stop it.
2. Release fuel pressure. Refer to EC-153, "
Work Procedure".
CAUTION:
If CONSULT-III is not used to release fuel pr essure leave the fuel pump fuse disconnected until
step 7.
3. Remove fuel pump fuse in IPDM E/R. NOTE:
 For the fuse number, refer to EC-114, "
Wiring Diagram".
 For the fuse arrangement, refer to PG-143, "
Fuse, Connector and Terminal Arrangement".
4. Remove engine cover. Refer to EM-25, "
Exploded View".
5. Remove ignition coil and spark plug from each cylinder. Refer to EM-29, "
Exploded View".
6. Connect engine tachometer (not required in use of CONSULT-III).
7. Install the compression tester with Tool [SST: EG15050500 (J- 45402)] into the spark plug hole.
8. Measure compression pressure using compressi on gauge connected with flexible type adapter (commer-
cial service tool).
9. With accelerator pedal fully depressed, turn ignition switch to “START” for cranking. When the gauge pointer stabilizes, read the compression pressure and the engine rpm. Perform these steps to check each
cylinder.
CAUTION:
 Measure a six-cylinder under the same conditio ns since a measurement depends on measure-
ment conditions (engine water temperature, etc.).
 Always use a fully changed battery to obtain the specified engine speed.
 If the engine speed is out of the specified range, c heck battery liquid for proper gravity. Check the
engine speed again with normal battery gravity. Refer to PG-159, "
How to Handle Battery".
 If compression pressure is below the minimum value, check valve clearances and parts associated with combustion chamber (valve, valve seat, piston, pi ston ring, cylinder bore, cylinder head, cylinder head
gasket). After checking, measure compression pressure again.
 If a cylinder has low compression pressure, pour a 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, pi ston rings may be worn out or damaged. Check pis-
ton rings and replace if necessary. Refer to EM-107, "
Disassembly and Assembly".
- 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. Refer to EM-107, "
Dis-
assembly and Assembly".
 If two adjacent cylinders have respectively low co mpression 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. Refer to EM-87, "
Removal and Installation".
10. After inspection is completed, install removed parts.
11. Start the engine, and check that the engine runs smoothly.
WBIA0605E
Compression pressure : Refer to EM-132, "GeneralSpecification".
Revision: 2010 May2011 QX56

NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTINGEM-19
< SYMPTOM DIAGNOSIS >
C
DE
F
G H
I
J
K L
M A
EM
NP
O
Use the Chart Below to Help You Find the Cause of the SymptomINFOID:0000000006289523
1. Locate the area where noise occurs.
2. Confirm the type of noise.
3. Specify the operating condition of the engine.
4. Check specified noise source.
If necessary, repair or replace these parts.
A: Closely related B: Related C: Sometimes related —: Not related Location
of noise Type of
noise Operating condition of engine
Source of noise Check item Refer-
ence page
Before
warm- up After
warm- up When
start- ing When
idling When
racing While
driving
Top of en-
gine
Rocker
cover
Cylinder
head Ticking or
clicking
CA—AB— Tappet
noiseValve clearance
EM-12
Rattle C A — A B C Camshaft
bearing
noiseCamshaft runout
Camshaft journal oil
clearance
EM-77
Crank-
shaft pul-
ley
Cylinder
block
(Side of
engine)
Oil panSlap or
knock
—A—B B—
Piston pin
noisePiston to piston pin oil
clearance
Connecting rod bushing
oil clearance
EM-115
Slap or
rap
A——B B A
Piston
slap noisePiston to cylinder bore
clearance
Piston ring side clear-
ance
Piston ring end gap
Connecting rod bend
and torsion
EM-115
Knock A B C B B B
Connect-
ing rod
bearing
noiseConnecting rod bushing
oil clearance
Connecting rod bearing
oil clearance
EM-115
Knock A B — A B C
Main bear-
ing noiseMain bearing oil clear-
ance
Crankshaft runout
EM-115
Front of
engine
Timing
chain caseTapping or
ticking
AA—BBB Timing
chain and
timing
chain ten-
sioner
noiseTiming chain cracks
and wears
Timing chain tensioner
operation
EM-72
Front of
engineSqueak-
ing or fizz-
ing
AB—B—C Drive belts
(Sticking
or slip-
ping)Drive belts deflection
EM-20
CreakingABABAB Drive belts
(Slipping)Idler pulley bearing op-
eration
Squall
Creak AB—BAB Water
pump
noiseWater pump operation
CO-19
Revision: 2010 May2011 QX56

EM-20
< PERIODIC MAINTENANCE >
DRIVE BELTS
PERIODIC MAINTENANCE
DRIVE BELTS
Exploded ViewINFOID:0000000006289524
CheckingINFOID:0000000006289525
WARNING:
Be sure to perform the these steps when engine is stopped.
 Check that the indicator (C) (notch on fixed side) of each auto-tensioner is within the possible use range (A).
NOTE:
 Check the each auto-tensioners indication when the engine is cold.
 When new drive belts is installed, the indicator (notch on fixed side) should be within the range (B) in the\
figure.
 Visually check all drive belts for wear, damage or cracks.
 If the indicator (notch on fixed side) is out of the possible use range or drive belts are damaged, replace drive
belts.
Tension AdjustmentINFOID:0000000006289526
Refer to EM-132, "Drive Belts".
Removal and InstallationINFOID:0000000006289527
REMOVAL
1. Move reservoir tank to the position without the hindrance for work. Refer to CO-13, "Exploded View".
1. Drive belt 2. Power steering oil pump pulley 3. Alternator pulley
4. Crankshaft pulley 5. A/C compressor 6. Idler pulley
7. Cooling fan pulley 8. Water pump pulley 9. Drive belt auto-tensioner
A. Possible use range B. Range when new drive belt is in-
stalledC. Indicator
D. View D
JPBIA3264ZZ
Revision: 2010 May2011 QX56

EM-40
< REMOVAL AND INSTALLATION >
EXHAUST MANIFOLD AND THREE WAY CATALYST
EXHAUST MANIFOLD AND THREE WAY CATALYST
Exploded ViewINFOID:0000000006289550
Removal and InstallationINFOID:0000000006289551
REMOVAL
WARNING:
Perform the work when the exhaust and cooling system have cooled sufficiently.
1. Drain engine coolant from radiator. Refer to CO-8, "
Draining".
CAUTION:
 Perform this step when the engine is cold.
 Never spill engine coolant on drive belt.
2. Remove reservoir tank. Refer to CO-13, "
Exploded View".
3. Remove drive belt. Refer to EM-20, "
Removal and Installation".
4. Remove power steering oil pump. Refer to ST-48, "
Exploded View".
5. Remove radiator. Refer to CO-13, "
Exploded View".
6. Remove front under cover. Refer to EXT-25, "
Exploded View".
7. Remove front wheels and tires. Refer to WT-64, "
Exploded View".
8. Remove A/C compressor. Refer to HA-30, "
Exploded View".
9. Remove alternator and alternator bracket. Refer to CHG-25, "
Exploded View".
10. Remove exhaust front tube (bank 1 and bank 2). Refer to EX-5, "
Exploded View".
1. Air fuel ratio sensor 1 (bank 2) 2. Exhaust manifold cover (bank 2) 3. Exhaust manifold and three way cat-
alyst (bank 2)
4. Gasket 5. Exhaust manifold and three way cat-
alyst (bank 1)6. Exhaust manifold cover (bank 1)
7. Air fuel ratio sensor 1 (bank 1)
Refer to GI-4, "
Components" for symbols in the figure.
JSBIA0389GB
Revision: 2010 May2011 QX56

HIGH PRESSURE FUEL PUMP AND FUEL HOSEEM-45
< REMOVAL AND INSTALLATION >
C
DE
F
G H
I
J
K L
M A
EM
NP
O
 To keep clean the connecting portion and to avoid dam-
age and foreign materials, cover them completely with
plastic bags, etc. or a similar item.
8. Disconnect harness connector from low fuel pressure sensor.
9. Remove fuel hose assembly.
10. Remove fuel pressure sensor. CAUTION:
 Never allow water and foreign mate rials enter into the connector.
 Never reuse the dropped sensor.
 Carefully handle sensor avoiding shocks.
 Use hex head support installation fo r removal and installation of sensor.
 The contact surface of gasket must not have any stain or scoring by dust etc.
INSTALLATION
1. Install O-ring to high pressure fuel pump. When handi ng new O-ring, paying attention to the following cau-
tion items:
CAUTION:
 Handle O-ring with bare hands. Never wear gloves.
 Lubricate O-ring with new engine oil.
 Never clean O-ring with solvent.
 Check that O-ring and its mating pa rt are free of foreign material.
 When installing O-ring, be careful not to scratch it with tool or fingernails. Also be careful not to
twist or stretch O-ring. If O-ring was stretched wh ile it was being attached, never insert it quickly
into fuel tube.
 Insert new O-ring straight into fu el rail. Never decenter or twist it.
2. Install fuel pressure sensor.
3. Install fuel hose assembly.  Temporarily tighten mounting bolt (A) as shown in the figure.
4. Install high pressure fuel pump to front cover. CAUTION:
After removing lifter, replace lifter with a new one.
5. Connect fuel feed hose to high pressure fuel pump. NOTE:
 Never allow the machined edge of the high pr essure fuel pump to contact with gasket.
 The gasket contact area must be free of dust and scratches.
PBIC2205E
: Engine front
JPBIA4250ZZ
Revision: 2010 May2011 QX56

FUEL INJECTOR AND FUEL TUBEEM-53
< REMOVAL AND INSTALLATION >
C
DE
F
G H
I
J
K L
M A
EM
NP
O
 Apply engine oil to O-ring.
 Tighten mounting bolts in numerical order as shown in the fig-
ure.
8. Install fuel feed tube (pump side) to fuel feed tube (bank side) as per the following:
CAUTION:
Never reuse fuel feed tube (pump side).
a. Apply engine oil to flare screw parts of high pr essure pump side and fuel feed tube (bank side) side.
b. Manually tighten 2 flare nuts without using a t ool until they are seated to screw thread.
c. Tighten mounting bolt (A).
d. Tighten flare nuts in numerical order as shown in the figure.
9. Install in the reverse order of removal.
InspectionINFOID:0000000006289558
INSPECTION AFTER INSTALLATION
Check for Fuel Leakage
1. Turn ignition switch “ON” (with the engine stopped). With fuel pressure applied to fuel piping, check that
there is no fuel leakage at connection points.
NOTE:
Use mirrors for checking at points out of clear sight.
2. Start the engine. With engine speed increased, check again that there is no fuel leakage at connection
points.
CAUTION:
Never touch the engine immediately after it is stopped because the engine is extremely hot.
JPBIA3924ZZ
: Engine front
JSBIA0355ZZ
B :To high pressure fuel pump
: Engine front
JSBIA0356ZZ
Revision: 2010 May2011 QX56

EM-58
< REMOVAL AND INSTALLATION >
OIL PAN (UPPER)
Removal and Installation
INFOID:0000000006289563
REMOVAL
WARNING:
To avoid the danger of being scalded, never drain engine oil when engine is hot.
1. Remove oil filter. Refer to LU-9, "
Removal and Installation".
2. Remove oil cooler. Refer to LU-11, "
Exploded View".
3. Move A/C compressor to the position without the hindrance for work. Refer to HA-30, "
Exploded View".
4. Remove oil level gauge and oil level gauge guide.
5. Remove oil pressure switch and oil temperature sensor if necessary.
6. Remove rear plate cover.
7. Remove protector A and protector B. Refer to SCS-32, "
FRONT TUBE ASSEMBLY : Exploded View".
8. Remove front suspension rear cross member. Refer to TM-205, "
2WD : Exploded View" (2WD models) or
TM-208, "
4WD : Exploded View" (4WD models).
9. Remove steering gear assembly. Refer to ST-41, "
Exploded View".
10. Remove front final drive assembly. Refer to DLN-162, "
Exploded View".
11. Remove oil pan (lower). Refer to EM-54, "
Exploded View".
12. Remove oil strainer. Refer to EM-54, "
Exploded View".
13. Remove bolts fixing oil pan (upper) to transmission assembly.
14. Remove oil pan (upper) as per the following:
a. Loosen mounting bolts in the reverse order as shown in the fig- ure with power tool to remove.
NOTE:
Disregard No. 9, 16 when loosening.
b. Insert a suitable tool into the notch at oil pan (upper) (1) as shown.
 Pry off case by moving a suitable tool.
CAUTION:
Be careful not to damage the mating surfaces.
15. Remove O-ring from bottom of cylinder block and oil pump.
16. Remove oil pressure switch and oil temperature sensor, if necessary.
INSTALLATION
1. Install oil pan (upper) as per the following:
: Engine front
JPBIA3502ZZ
: Engine front
JPBIA2299ZZ
Revision: 2010 May2011 QX56

OIL PAN (UPPER)EM-59
< REMOVAL AND INSTALLATION >
C
DE
F
G H
I
J
K L
M A
EM
NP
O
a. Use a scraper (A) to remove old liquid gasket from mating sur-
faces.
 Also remove the old liquid gasket from mating surface of cylin-der block.
 Remove old liquid gasket from the bolt holes and threads.
CAUTION:
Never scratch or damage th e mating surfaces when clean-
ing off old liquid gasket.
b. Install new O-rings on the bottom of cylinder block and oil pump.
c. Apply a continuous bead of liquid gasket with tube pre sser (commercial service tool) to the cylinder block
mating surfaces of oil pan (upper) to a limited portion as shown in the figure.
Use Genuine RTV silicone sealant or equivalent. Refer to GI-22, "
Recommended Chemical Prod-
ucts and Sealants".
CAUTION:
Attaching must be done with in 5 minutes after coating.
d. Tighten mounting bolts in numerical order as shown in the fig- ure.
CAUTION:
Install avoiding misal ignment of O-rings.
NOTE:
Tighten mounting bolts No. 1 and 2 in two steps. The numerical
order No. 9 and 16 shown second steps.
 There are four types of mounting bolts. Refer to the following for locating bolts.
e. Tighten transmission joint bolts.
f. Install rear plate cover.
2. Install oil strainer.
JPBIA3503ZZ
a. : 5.5 - 7.5 mm (0.217 - 0.295 in) b. : φ4.0 - 5.0 mm (0.157 - 0.197 in)
: Engine front
JPBIA3504ZZ
: Engine front
JPBIA3502ZZ
Order number for tightening 17, 18 2 (16), 3, 5, 6, 7, 8, 10,
11, 14, 15 1(9), 4 12, 13
Bolt size M6 M8
Bolt length 45 mm (1.77 in) 25 mm (0.98 in) 30.0 mm (1.18 in) 120 mm (4.72 in)
Tightening torque 9.0 N· (0.92 kg-m, 80
in-lb) 22.0 N·m (2.2 kg-m, 16 ft-lb)
Revision: 2010 May2011 QX56