NISSAN PICK-UP 1998 Repair Manual

2. Remove rocker cover.
3. Remove rocker shaft assembly.
4. Remove valve spring.
5. Remove valve oil seals.
6. Apply engine oil to valve oil seal and install it in place.
DEM029-A
SEM626BA
SEM646BA
DEM040
OIL SEAL REPLACEMENTTD
EM-68

WARNING:
lPosition vehicle on a flat and solid surface.
lPlace chocks at front and back of rear wheels.
lDo not remove engine until exhaust system has com-
pletely cooled off.
Otherwise, you may burn yourself and/or fire may break
out in fuel line.
lBe sure to hoist engine and transmission in a safe man-
ner.
lFor engines not equipped with engine slingers, attach
proper slingers and bolts described in PARTS CATA-
LOG.
CAUTION:
lWhen lifting engine, be sure to clear surrounding parts.
Take special care near accelerator wire casing, brake
lines and brake master cylinder.
lIn lifting the engine, always use engine slingers in a safe
manner.
lFor 4WD models, apply sealant between engine and
transmission. Refer to MT section (``Removal and Instal-
lation'').
SEM613FN
ENGINE REMOVALTD
EM-69

Removal
1. Remove engine undercover and hood.
2. Drain engine coolant.
3. Remove vacuum hoses, fuel tubes, wires, harnesses and
connectors and so on.
4. Remove radiator, shroud and cooling fan.
5. Remove drive belts.
6. Remove power steering oil pump and air conditioner com-
pressor.
7. Remove front exhaust tube.
8. Remove transmission from vehicle.
Refer to MT section.
9. Install engine slingers.
10. Hoist engine with engine slingers and remove engine mount-
ing bolts from both sides.
11. Remove engine from vehicle.
Installation
lInstall in reverse order of removal.
DEM021
ENGINE REMOVALTD
EM-70

DEM065-A
.
ENGINE OVERHAULTD
EM-71

Disassembly
PISTON AND CRANKSHAFT
1. Remove oil filter.
2. Place engine on work stand.
3. Drain coolant and oil.
4. Remove drive belts.
5. Remove cylinder head.
6. Remove oil pan.
7. Remove crankshaft pulley.
8. Remove water pump.
9. Remove timing gear case.
lRemove dust cover with a seal cutter.
lIf the timing case is hard to remove due to liquid gasket,
pry it off with a suitable tool at the cutout section.
SEM650B
SEM651B
DEM045
DEM062
DEM046
ENGINE OVERHAULTD
EM-72

10. Remove injection pump gear.
lBe careful not to lose the woodruff key during injection pump
removal.
11. Remove idler gear and idler gear shaft.
12. Remove camshaft gear, camshaft and valve lifters.
13. Remove oil pump assembly.
14. Remove crankshaft gear.
15. Remove flywheel and rear plate.
16. Remove connecting rod caps.
17. Remove pistons.
lRemove the connecting rod in such a way that it does not
interfere with oil jet.
DEM043
DEM044
DEM047
DEM048
ENGINE OVERHAULTD
Disassembly (Cont'd)
EM-73

18. Remove rear oil seal retainer assembly.
19. Remove bearing cap and crankshaft.
Place the bearings and caps in their proper order.
Inspection and Replacement
CYLINDER BLOCK DISTORTION
If beyond the specified limit, replace it.
Cylinder block distortion: mm (in)
Standard
Less than 0.05 (0.0020)
Limit
0.2 (0.008)
lRemove all traces of gasket from the cylinder block. Do not
allow pieces of the gasket to enter the oil and cooling water
passages during gasket removal.
CYLINDER LINER WEAR
1. Measure cylinder liner bore for out-of-round and taper with a
bore gauge. If beyond the limit, replace cylinder liner.
Standard inside diameter:
92.900 - 92.930 mm (3.6575 - 3.6587 in)
Refer to SDS, EM-102.
Wear limit:
0.20 mm (0.0079 in)
Out-of-round (X þ Y) standard:
0.020 mm (0.0008 in)
Taper (A þ B) standard:
0.020 mm (0.0008 in)
SEM657B
SEM658B
SEM038
DEM067
ENGINE OVERHAULTD
Disassembly (Cont'd)
EM-74

2. Check for scratches or seizure. If seizure is found, replace
cylinder liner.
3. Check amount of projection of cylinder liner.
Cylinder liner projection:
Standard
0.02 - 0.09 mm (0.0008 - 0.0035 in)
Deviation of each cylinder:
Less than 0.05 mm (0.0020 in)
CYLINDER LINER
Replacement
1. Remove cylinder liner with Tool.
2. Install cylinder liner with Tool.
3. Check amount of projection of cylinder liner.
PISTON TO CYLINDER WALL CLEARANCE
1. Measure piston and cylinder bore diameter.
Piston diameter ``A'':
Refer to SDS, EM-103.
Measuring point ``a''
(Distance from the top): mm (in)
70 (2.76)
2. Check that piston clearance is within the specification.
Piston clearance:
0.05 - 0.07 mm (0.0020 - 0.0028 in)
SEM920A
SEM849
SEM659B
SEM660B
ENGINE OVERHAULTD
Inspection and Replacement (Cont'd)
EM-75

Combination of piston and cylinder bore
Use the same piston grade in one engine.
Cylinder bore
grade numberPiston grade number
123
1OKNGNG
2 Possible OK NG
3 Possible Possible OK
Refer to SDS, EM-102, for finding cylinder bore grade number.
PISTON AND PISTON PIN CLEARANCE
Check clearance between pistons and piston pins.
Clearance (A þ B): mm (in)
Standard
þ0.003 to 0.012 (þ0.0001 to 0.0005)
Limit
Less than 0.10 (0.0039)
PISTON RING SIDE CLEARANCE
Side clearance: mm (in)
Top ring
0.06 - 0.10 (0.0024 - 0.0039)
2nd ring
0.04 - 0.08 (0.0016 - 0.0031)
Oil ring
0.02 - 0.06 (0.0008 - 0.0024)
Max. limit of side clearance: mm (in)
Top ring 0.50 (0.0197)
2nd ring 0.30 (0.0118)
Oil ring 0.15 (0.0059)
PISTON RING GAP
Standard ring gap: mm (in)
Top ring
0.30 - 0.45 (0.0118 - 0.0177)
2nd ring
0.20 - 0.35 (0.0079 - 0.0138)
Oil ring
0.15 - 0.35 (0.0059 - 0.0138)
Max. limit of ring gap:
1.5 mm (0.059 in)
DEM109
SEM424
SEM024AB
SEM905
ENGINE OVERHAULTD
Inspection and Replacement (Cont'd)
EM-76

MAIN BEARING CLEARANCE
1. Install main bearings to cylinder block and main bearing cap.
2. Install main bearing cap to cylinder block.
lApply engine oil to the thread portion and seating sur-
face of bolts.
lTighten all bolts with specified torque in correct order
and in two or three stages. Refer to EM-88.
3. Measure inside diameter ``A'' of main bearing.
4. Measure outside diameter ``Dm'' of main journal in crank-
shaft.
5. Calculate main bearing clearance.
Main bearing clearance=AþDm
Standard:
0.035 - 0.087 mm (0.0014 - 0.0034 in)
Limit:
Less than 0.15 mm (0.0059 in)
CONNECTING ROD BEARING CLEARANCE
1. Install connecting rod bearing to connecting rod and cap.
2. Install connecting rod cap to connecting rod and tighten with
specified torque.
Apply engine oil to the thread portion of bolts and seating
surface of nuts.
3. Measure inside diameter ``A'' of bearing.
4. Measure outside diameter ``Dp'' of pin journal in crankshaft.
5. Calculate connecting rod bearing clearance.
Connecting rod bearing clearance=AþDp
Standard:
0.035 - 0.081 mm (0.0014 - 0.0032 in)
Limit:
Less than 0.15 mm (0.0059 in)
CONNECTING ROD BEND AND TORSION
Bend and torsion: mm (in)
Limit
0.075 (0.0030) per 100 (3.94) length
SEM174B
SEM413B
SEM507A
SEM038F
ENGINE OVERHAULTD
Inspection and Replacement (Cont'd)
EM-77