engine NISSAN PATROL 1998 Y61 / 5.G Engine Mechanical Owner's Manual

Checking
Check valve clearance while engine is warm and not running.
1. Remove rocker cover.
2. Set No. 1 cylinder at TDC on its compression stroke.
+Align pointer with TDC mark on crankshaft pulley.
+Check that valve lifters on No. 1 cylinder are loose and valve
lifters on No. 6 are tight.
If not, turn crankshaft one revolution (360É) and align as
described above.
3. Check only those valves shown in the ®gure.
No. 1 No. 2 No. 3 No. 4 No. 5 No. 6
INT EXH INT EXH INT EXH INT EXH INT EXH INT EXH
No. 1 cylin-
der at TDCjjj jj j
+Using a feeler gauge, measure clearance between valve lifter
and camshaft.
+Record any valve clearance measurements which are out of
speci®cation. They will be used later to determine the required
replacement adjusting shim.
Valve clearance for checking (Hot):
Intake
0.28 - 0.38 mm (0.011 - 0.015 in)
Exhaust
0.32 - 0.42 mm (0.013 - 0.017 in)
4. Turn crankshaft one revolution (360É) and align mark on crank-
shaft pulley with pointer.
5. Check only those valves shown in the ®gure.
No. 1 No. 2 No. 3 No. 4 No. 5 No. 6
INT EXH INT EXH INT EXH INT EXH INT EXH INT EXH
No. 6 cylin-
der at TDCjj jj jj
+Use the same procedure as mentioned in step 4.
6. If all valve clearances are within speci®cation, install the follow-
ing parts:
+Rocker cover
SEM790F
SEM799F
SEM634F
SEM800F
VALVE CLEARANCE
EM-41

Adjusting
Adjust valve clearance while engine is cold.
1. Turn crankshaft. Position cam lobe upward on camshaft for
valve that must be adjusted.
2. Place Tool (A) around camshaft as shown in ®gure.
Before placing Tool (A), rotate notch toward center of cylinder
head. (See ®gure.) This will simplify shim removal later.
CAUTION:
Be careful not to damage cam surface with Tool (A).
3. Rotate Tool (A) (See ®gure.) so that valve lifter is pushed down.
4. Place Tool (B) between camshaft and valve lifter to retain valve
lifter.
CAUTION:
+Tool (B) must be placed as close to camshaft bracket as
possible.
+Be careful not to damage cam surface with Tool (B).
5. Remove Tool (A).
6. Remove adjusting shim using a small screwdriver and a mag-
netic ®nger.
7. Determine replacement adjusting shim size using the following
formula.
+Use a micrometer to determine thickness of removed shim.
+Calculate thickness of new adjusting shim so valve clearance
comes within speci®ed values.
R = Thickness of removed shim
N = Thickness of new shim
M = Measured valve clearance
S = Standard valve clearance
Unit: mm (in)
HOTIntake 0.28 - 0.38 (0.0110 - 0.0150)
Exhaust 0.32 - 0.42 (0.0126 - 0.0165)
COLDIntake 0.26 - 0.34 (0.0102 - 0.0134)
Exhaust 0.30 - 0.38 (0.0118 - 0.0150)
Intake:
N=R+[MþS]
Exhaust:
N=R+[MþS]
Shims are available in 15 sizes from 2.20 mm (0.0866 in) to 2.90
mm (0.1142 in), in steps of 0.05 mm (0.0020 in).
SEM636F
SEM637F
SEM638F
SEM145D
VALVE CLEARANCE
EM-42

SEM433C
ENGINE REMOVAL
EM-44

Removal
1. Remove engine, transmission and transfer's undercovers, oil
pan guard and hood.
2. Drain engine coolant.
3. Remove charge air cooler assembly.
4. Remove vacuum hoses, fuel tubes, harnesses, and connectors
and so on.
5. Remove radiator assembly.
6. Remove drive belts.
7. Remove power steering oil pump, alternator and air conditioner
compressor.
8. Remove starter motor assembly.
9. Remove front exhaust tube.
10. Remove transmission from vehicle.
Refer to MT section.
11. Hoist engine with engine slingers and remove engine mounting
bolts from both sides.
12. Remove engine from vehicle.
Installation
+Install in reverse order of removal.
ENGINE REMOVAL
EM-45

CAUTION:
+When installing sliding parts such as bearings and
pistons, apply engine oil to the sliding surfaces.
+Place removed parts, such as bearings and bearing caps,
in their proper order and direction.
+When installing connecting rod bolts and main bearing cap
bolts, apply new engine oil to threads and seating surfaces
of nuts.
+Do not allow any magnetic materials to contact the ring
gear teeth of drive plate.
Disassembly
PISTON AND CRANKSHAFT
1. Place engine on a work stand.
2. Remove timing belt and injection pump.
3. Drain coolant and remove water pump.
4. Remove front cover.
5. Drain oil.
6. Remove oil pan and oil pump.
7. Remove cylinder head.
8. Remove pistons with connecting rod.
+To disassemble piston and connecting rod, remove snap ring
®rst. Then heat piston to 60 to 70ÉC (140 to 158ÉF) and use
piston pin press to remove pin.
+When piston rings are not replaced, make sure that piston
rings are mounted in their original positions.
+When replacing piston rings, if there is no punchmark,
install with either side up.
9. Remove bearing cap bolts and main bearing caps in the order
shown, then remove crankshaft.
+Loosen bolts in two or three steps.
Inspection
PISTON AND PISTON PIN CLEARANCE
1. Measure inner diameter of piston pin hole ``dp''.
Standard diameter ``dp'':
26.995 - 27.005 mm (1.0628 - 1.0632 in)
SEM750B
SEM877B
SEM801F
SEM672E
CYLINDER BLOCK
EM-47

Assembly
PISTON
1. Install new snap ring on one side of piston pin hole.
2. Heat piston to 60 to 70ÉC (140 to 158ÉF) and assemble piston,
piston pin, connecting rod and new snap ring.
+Align the direction of piston and connecting rod.
+Numbers stamped on connecting rod and cap correspond
to each cylinder.
+After assembly, make sure connecting rod swings
smoothly.
3. Set piston rings as shown.
CAUTION:
+When piston rings are not replaced, make sure that piston
rings are mounted in their original positions.
+Install new piston rings either side up if there is no punch-
mark.
+Align piston rings so that end gaps are positioned as
shown.
CRANKSHAFT
1. Set main bearings in their proper positions on cylinder block
and main bearing cap.
+Con®rm that correct main bearings are selected by using
Method A or Method B. Refer to EM-52.
+Apply new engine oil to bearing surfaces.
SEM146B
SEM754B
SEM156B
SEM160B
SEM157B
CYLINDER BLOCK
EM-54

2. Install crankshaft and main bearing caps and tighten bolts to
the speci®ed torque.
+Apply new engine oil to the bolt thread and seat surface.
+Prior to tightening bearing cap bolts, shift crankshaft back
and forth to properly seat the bearing cap.
+Tighten bearing cap bolts gradually in two or three steps.
Start with center bearing and move outward as shown in
®gure.
+After securing bearing cap bolts, make sure crankshaft
turns smoothly by hand.
3. Measure crankshaft end play.
Crankshaft end play:
Standard
0.050 - 0.18 mm (0.0020 - 0.0071 in)
Limit
0.30 mm (0.0118 in)
If beyond the limit, replace thrust bearing with a new one.
4. Install connecting rod bearings in connecting rods and connect-
ing rod caps.
+Con®rm that correct bearings are selected. Refer to ``Con-
necting rod bearing (Big end)'', EM-52.
+Install bearings so that oil hole in connecting rod aligns
with oil hole of bearing.
+Apply new engine oil to bearing surfaces, bolt threads and
seating surfaces.
5. Install pistons with connecting rods.
a. Install them into corresponding cylinders with Tool.
+Make sure connecting rod does not scratch cylinder wall.
+Make sure connecting rod bolts do not scratch crankshaft
pin journals.
+Arrange so that front mark on piston head faces toward
front of engine.
+Apply new engine oil to piston rings and sliding surface of
piston.
b. Install connecting rod caps.
+Apply new engine oil to bolt threads and nut seating sur-
faces.
Tighten connecting rod cap nuts using the following procedure.
(1) Tighten to 14 to 16 Nzm
(1.4 to 1.6 kg-m, 10 to 12 ft-lb).
(2) Turn nuts 60 to 65É clockwise with an angle wrench. If
an angle wrench is not available, tighten nuts to 37 to
45 Nzm (3.8 to 4.6 kg-m, 27 to 33 ft-lb).
SEM801FA
SEM756B
SEM757B
SEM936A
SEM759B
CYLINDER BLOCK
Assembly (Cont'd)
EM-55