ISUZU TROOPER 1995 Workshop Manual

mm(in)
Standard Limit
0.026-0.049 (0.001 0-0.0019) 0.12 (0.0047)
Fig. 6A-70
12. Clean the plastigage from the bearings and the
crankshaft.
Remove the crankshaft and the bearings.
Crankshaft inspection
Inspect the surface ofthe crankshaft journal and crank
pins
for excessive wear and damage.
Inspect the oil seal fitting surfaces for excessive wear
and damage.
Inspect the oil ports for obstructions.
(L!] INSPECTION AND REPAIR
1. Carefully set the crankshaft on the V-blocks.
Slowly
rotate the crankshaft and measure the
runout.
If the crankshaft runout exceeds the
specified
limit, the crankshaft must be replaced
(Fig. 6A-71).
Runout
mm (in) 0.04 (0.0015)
Fig. 6A-71
2. Measure the diameter and the uneven wear of
main journal and crank pin (Fig. 6A-72).
l'fil If the crankshaft wear exceeds the specified limit,
~ crankshaft must be replaced.
GENERAL ENGINE MECHANICAL &A-25
mm(in)
Main
journal diameter 63.918-63.933 (2.5165-2.5170)
Crank pin diameter 53.922-53.937 (2.1229-2.1235)
Uneven wear
limit 0.005
(0.0002)
Fig. 6A-72
CRANKSHAFT BEARING SELECTION
When installing new crankshaft bearings or replacing
bearings, refer to the selection table below.
Select
and install the new crankshaft bearings, paying
close attention to the cylinder block journal hole diameter size mark and the crankshaft journal ®
diameter size mark (Fig. 6A-73, Fig. 6A-74).
Fig. 6A-73
Crankshaft journal diameter classification symbol
1-----
#2~#3 #1 #4
~ --:--
A ;:.,,
A-A face
Fig. 6A-74

6A-26 GENERAL ENGINE MECHANICAL
NOTE:
Take care to ensure the bearings are positioned
correctly.
Upper and lower
#1,4
CD Size Mark
1
2
3
r-
1:=
II-
~
Upper
#2,3
Fig. 6A-75
Main Bearing
Bore Diameter
68.994-69.000
(2. 7163-2. 7165)
68.987-68.993
(2. 7160-2. 7163)
68.980-68.986
(2.7157-2.7160)
Lower
#2,3
Crank Shaft Main
Journal Diameter
63.918-63.925
(2.5165-2.5167)
63.926-63.933
(2.5168-2.5170)
63.918-63.925
(2.5165-2.5167)
63.926-63.933
(2.5168-2.5170)
63.918-63.925
(2.5165-2.5167)
63.926-63.933
(2.5168-2.5170)
mm (in)
® Crank Shaft Crank Shaft
Size Bearing Bearing
Oil
Clearance
Mark Size
Mark Size Mark (Reference)
(Upper Side) (Lower Side)
2 Brown
Brown
0.030-0.049
(0.0012-0.0019)
0.028-0.047
1 (0.0011-0.0019)
Green Green 0.029-0.048 2 (0.0011-0.0019) 0.027-0.046
1 (0.0011-0.0018)
Yellow Yellow 0.028-0.047 2 (0.0011-0.0019) 0.026-0.045
1 Pink Pink (0.001 0-0.0018)
•

l•!•l REASSEMBL V
12. Crankshaft
• Install the main bearings to the cylinder block
and the main bearing caps.
1 .. 1• Be sure that they are positioned correctly (Fig.
6A-76).
1~1· Apply new engine oil to the upper and lower
main bearing faces.
• Carefully mount the crankshaft.
• Apply engine oil to the thrust washer.
1 .. 1• Assemble the thrust washer to the No.3
bearing
journal. The oil grooves must face the
crankshaft (Fig. 6A-77).
Upper and lower
#1.4
~
~
IH
t=
Upper
#2,3
Fig. 6A-76
Fig. 6A-77
11. Main bearing cap
Lower
#2,3
B • Apply engine oil to the
threads and the seating
' faces
of the bolts.
r=1 • Install bearing caps in the order shown with the
L:::.l No.1 as the front most bearing cap. (Fig. 6A-78)
• Semi-tighten all of the bolts.
Finally,
tighten all the bolts to specification in
the
order shown (Fig. 6A-79).
1~1 Torque N·m (lb·ft) 39 (29)
After the final tightening, check to see that the
crankshaft rotates
smoothly.
GENERAL ENGINE MECHANICAL 6A-27
Forward
Fig. 6A-78
Fig. 6A-79
10. Rear oil seal
liill • Re~ove the oil_from the cylinder block and the
U retainer mounting surface.
rEil • Apply sealant (TB-1207B or equivalen_t) to the
1.:::!!.1 retainer mounting surface, follow~ng the
pattern shown in the
illustration (Fig. 6A-80).
• Apply engine oil to the oil seal lip.
• Align
the cylinder block dowel pin holes with
the rear retainer dowel pins.
• Tighten the rear retainer fixing bolts. New bolts
should
be used when installing rear retainer.
~~~ Torque N·m (lb·ft) 18 (13)
NOTE:
Be very careful notto disengage the oil seal garter
spring during
installation of the rear retainer.
If the seal was removed from retainer for
replacement, apply engine oil to the oil seal lip
and install the oil seal using installer (Fig. 6A-81).
l®llnstaller: J-39201

6A-28 GENERAL ENGINE MECHANICAL
Fig. 6A-80
/
Fig. 6A-81
9. Flywheel
1) Thoroughly clean and remove the oil from
the threads
of crankshaft.
1!t1 2) Remove the oil from the crankshaft and
LQI flywheel mounting faces.
3) Mount the flywheel on the crankshaft and
then
install the washer.
4) Hold the crankshaft to prevent from rotating
and
bolts in the order shown to the specified
torque. (Fig. 6A-82)
~~~ Torque N·m (lb·ft) I ___ ___,_ ___ _ 54 (40)
NOTE:
• Do not reuse the bolt.
•
Do not apply oil or thread lock to the bolt.
Fig. 6A-82
8. Piston and connecting rod assembly
D • Apply engine oil to the cylinder bores, the
l:J connecting rod bearings and the crankshaft
pins. Check to see that the piston ring end gaps are
correctly positioned (Fig. 6A-83).
Insert the piston/connecting rod assemblies
into each cylinder with the piston ring
compressor. The
front marks must be facing the front of the
engine (Fig. 6A-84).
Oil ring ---~====-~::F::::::.===~~t---No. 1
side rail Compression (Lower) ring Front mark
No .2--~~:::::=:e!::::!-;::::!!;~~·-Oil ring
Compression side rail ring (Upper)
Fig. 6A-83
Front mark
Front mark
Fig. 6A-84
•

1£41• Match the numbered caps with the numbers on
the connecting rods.
Align the punched marks
on the connecting rods and caps.
1'l:::r.1• Apply engine oil to the threads and seating
faces
of the nuts.
• Tighten the nuts
~~~ Torque N·m (lb·ft) 54 (40)
7.
After tightening the cap nuts, check to see that
the crankshaft rotates smoothly.
Oil gallery
• Tighten the bolts in 2 steps, in the order shown.
(Fig. 6A-85)
1~1 _________ 1_s_t,s_te~p ________ ~ __ 2_n_d __ st_e~p---
N·m (lb·ft) 29 (22) 55° -65°
Fig. 6A-85
6. Crankcase side bolts
• Tighten all the bolts to specification in the order
shown (Fig. 6A-86).
NOTE:
Do not apply engine oil to the crank case side
bolts.
~~~ Torque N·m (lb·ft) 39 (29)
Fig. 6A-86
5.
4.
3.
GENERAL ENGINE MECHANICAL 6A-29
Oil pump assembly
• Refer to "Oil pump installation" in this section.
Oil strainer and rubber ring
Oil pipe and rubber ring
• Tighten the bolts
I~I_T_o_rq...:....u_e_N_·_m_(:.._lb_·ft....:.)---!. ___ 1_9 _(1_4_) __ _
2. Oil pan
m 1) Completely remove all residual sealant,
~ lubricant and moisture from the sealing
surfaces. The surfaces must be perfectly
dry.
~~~2) Apply a correct width bead of sealant (TB-
1207C or its equivalent) to the contact
surfaces
of the oil pan. There must be no
gaps in the bead (Fig. 6A-87).
3) The oil pan must be installed within 5
minutes after
sealant application.
~~~4) Tighten the bolts and nuts to the specified
torque.
Torque
N-m (lb-in) 10 (87)
D
Fig. 6A-87
1. Cylinder head assembly
• Refer to Section 6A
1 "Cylinder head assembly
installation".

6A-30 GENERAL ENGINE MECHANICAL
PISTON AND CONNECTING ROD
1
~~ $ 7
2 6 Disassembly
steps
1. Cylinder head assembly 2. Cylinder head gasket 3. Oil pan
4. Oil pipe and rubber ring
5. Oil strainer and rubber ring
6. Oil gallery
7. Piston and connecting rod assembly 8. Piston ring
9. Piston pin
10. Piston
11. Connecting rod
Reassembly steps
To reassemble, follow the disassembly steps in the reverse order.
Fig. 6A-88
1•! .. 1 DISASSEMBLY
1. Cylinder head assembly.
• Refer to Section 6A 1 "Cylinder head Removal".
2. Cylinder head gasket
3. Oil pan
• Refer to Section 6A1 "Oil pan Removal".
4. Oil pipe and rubber ring
5. Oil strainer and rubber ring
6. Oil gallery
7. Piston and connecting rod assembly
NOTE:
Before removing piston and connecting rod
assembly, measure thrust clearance (page 6A-
33).
• Remove any ridge or carbon build up from the
top end of the cylinder.
8. Piston ring (Fig. 6A-89)
• Remove the piston rings with a piston ring
expander.
Arrange the removed piston rings in the
cylinder number order. Fig.
6A-89
9. Piston pin (Fig. 6A-90)
• Remove the piston pin using a piston pin
service set and piston
support with a press.
1®1 Piston pin service set: J-24086-C
NOTE: Keep the parts removed
from each cylinder separate.
All parts must be reinstalled in their original positions.
Heating the connecting rod
will permit easy removal of
the piston pin.

J-24086-SA ~---Press ram
Fig. 6A-90
10. Piston
11. Connecting rod
[1!) INSPECTION AND REPAIR
PISTON
AND PISTON RING
Pistons
Piston
Carefully clean away all the carbon adhering to the
piston head and the piston ring grooves.
NOTE:
Never use a wire brush to clean the pistons. Damage
will result.
Visually
check each piston for cracking, scoring, and
other signs
of excessive wear.
If any of the above conditions are present, the piston
must be replaced.
1~1 Piston Diameter
1. Measure the piston outside diameter with
micrometer at the piston grading position and a
right
angle to the piston pin (Fig. 6A-91 ).
Piston grading position (from piston head)
Piston
grc;d~"g position mm (in) 131.0 (1.2204)
Fig. 6A-91
GENERAL ENGINE MECHANICAL &A-31
Size Mark Outside
Diameter mm (in)
A 93.350-93.360 (3.6752-3.6756)
8 93.361 -93.370 (3.6756-3.6760)
c 93.371-93.380 (3.6760-3.6764)
Fig. 6A-92
The size mark
for piston outside diameter is
represented
by the "G" as shown in Figure. (Fig. 6A-92)
Measure the
cylinder bore inside diameter (refer to
"Inspection of the Cylinder Block" in this Section) (Fig.
6A-93).
Fig. 6A-93
Piston rings
Any worn or damaged part discovered during engine
overhaul must be replaced with a new one.
1. Ring end gap measurement
• Insert the piston ring into the bore (Fig. 6A-94).
• Push the ring by the piston, at a right angle to
the
wall, into the point at which the cylinder
bore diameter is the smallest.
•
Measure the ring end gap.
• Positioning mark is painted as shown in the
illustration (Fig. 6A-95).

6A-32 GENERAL ENGINE MECHANICAL
Fig. 6A-94
T mark (No.1 comp}, T1 mark (No.2 comp}
Fig. 6A-95
mm (in)
Standard Limit
Compression 1st 0.350-0.470 1.5
ring
Oil ring
~ 2.
(0.0138-0.0185) (0.0590)
2nd 0.450-0.600 1.5
(0.0177 -0.0236) (0.0590)
0.150-0.450
1.5
(0.0059-0.0177) (0.0590)
Measure the clearance between the piston
ring groove and the piston ring with a feeler
gauge. If the piston ring groove/piston ring
clearance exceeds the specified limit, the
piston must be replaced (Fig. 6A-96).
mm(in)
Standard Limit
Clearance
compression ring
0.016-0.038
(0.0006-0.0015) 0.15
(0.0059)
Fig. 6A-96
Piston pin
NOTE:
Do not reuse the old piston pin.
~1.
2.
Use a micrometer to measure the new piston
pin
outside diameter in both directions at
three different positions. (Fig. 6A-97).
Fig. 6A-97
-+
u
Measure the inside diameter of the
connecting rod small end. If the fitting
interference between the small end and pin
does not conform to the specified value, the
connecting rod must be replaced.
Standard mm (in) 0.020-0.041
(0.0008-0.0016)
•

3. Insert the new pin into the piston and rotate
it.
If the pin rotates smoothly with no
backlash, the clearance is normal. If there is
backlash or roughness, measure the
clearance. If the clearance exceeds the
specified
limit, the piston must be replaced.
mm (in)
Standard Limit
Clearance 0.007-0.020
0.040
(0.0003-0.0008) (0.0016)
Connecting rods
1. Check the connecting rod alignment (Fig. 6A-98).
If either the bend or the twist exceeds the
specified
limit, the connecting rod must be
replaced.
mm(in)
Standard
Limit
Bend per
100 mm (3.937 in)
0.15 (0.0059)
Twist per 100 mm (3.937 in) 0.20 (0.0078)
Fig. 6A-98
2. Measure the connecting rod thrust clearance.
Use a feeler gauge to measure the thrust
clearance at the big end of the connecting rod
(Fig. 6A-99).
If the clearance exceeds the specified limit, the
connecting rod
must be replaced.
3.
GENERAL ENGINE MECHANICAL 6A-33
mm(in)
Standard Limit
0.16-0.35
(0.0063-0.0138) 0.40
(0.0157)
Fig. 6A-99
Measure the
oil clearance between the
connecting rod and the crankshaft by:
1) Remove the connecting rod cap nuts and the
rod caps.
Arrange the removed rod caps in the
cylinder
number order.
2) Clean the rod bearings and the crankshaft
pins.
3) Carefully check the rod bearings.
If even one bearing is found to be damaged or
badly worn, the entire bearing assembly must
be replaced as a set. Reinstall the bearings in
their
original positions.
Apply plastigage to the crank pin (Fig. 6A-
100).
Fig. 6A-100
4) Reinstall the rod caps to their original
positions.
~~~ Tighten the rod caps.
Torque
N·m (lb·ft) 54 (40)
NOTE:
Do not allow the crankshaft to rotate.

6A-34 GENERAL ENGINE MECHANICAL
5) Remove the rod caps.
6) Measure the width of the plastigage and
determine the
oil clearance. If the oil
clearance
exceeds the limit, replace the rod
bearing
as a set (Fig. 6A-101).
mm(in)
Standard Limit
0.025-0.058
(0.001 0-0.0023) 0.12 (0.0047)
Fig. 6A-101
7) Clean the plastigage from the bearings and
the crankshaft pins.
1
Size Mark Big
end Bore
Diameter
A 56.994-57.000
(2.2439-2.2441)
B 56.988-56.994
(2.2436-2.2439)
c 56.982-56.988
(2.2434-2.2436)
1,.!•1 REASSEMBLY
11. Connecting-rod
10. Piston
9. Piston pin
Crankshaft
Pin Diameter
53.922-53.937
(2.1229-2.1235)
D • Apply a thin coat of engine oil to the piston pin.
r..::::J Try to insert the piston pin into the piston pin
hole with normal finger pressure.
NOTE:
•
When changing piston/connecting rod
combinations,
do not change the piston/piston
pin combination.
Take care
to ensure the difference piston parts
between
SOHC and DOHC engine. (Fig. 6A-1 03)
• Do not reuse the old piston pin.
Con-rod bearing selection (Fig. GA-1 02)
Select the install the new connecting rod bearings,
paying
close attention to the connecting rod big end
diameter size mark.
NOTE:
Take care not to confuse the alignment mark and the
size mark during the
installation procedure.
Connecting Rod
Bearing
Thickness
(Reference)
1.512-1.516
(0.0595-0.0597)
1.508-1.512
(0.0594-0.0595)
1.504-1.508
(0.0592-0.0594)
1 Size mark
Fig. 6A-1 02
mm (in)
Color of Oil Clearance
Size Mark
Yellow 0.025-0.054 (0.001 0-0.0021)
Green 0.027-0.056
(0.0011-0.0022)
Pink 0.029-0.058
(0.0011-0.0023)
Connecting rod mark DOHC W mark SOHC S mark
Fig. 6A-103
•