Mitsubishi S12A2, Service Manual

Page: 142 / 354

7-6
Chapter 7 ASSEMBLY OF BASIC ENGINE
1.7 Main Bearing Cap - Install
(1)
Make sure that the main bearings and thrust plates
installed to main bearing caps are evenly coated with
clean engine oil.
(2)
Install the main bearing cap so that its number stamp
lines up in numerical order from the front to rear of the
engine, and also the embossed part number side faces
toward the engine front (so that all rug grooves are
aligned on the same side).
(3)
Apply oil to the main bearing cap bolts and washers and
hand tighten them.
(4)
Tap the main bearing caps with a soft-head hammer
evenly to install them in position.
(5)
Apply oil to the side bolts and O-ring and hand tighten
them.
Main Bearing Cap - Install
(6)
Snug tighten the main bearing cap bolts and side bolts
except the rearmost ones, to the half of specified torque
in the specified tightening sequence as shown in the
illustration.
(7)
Tighten the main bearing cap bolts and side bolts
except the rearmost ones to the specified torque in the
specified sequence shown in the illustration.
(8)
Hand tighten the rearmost cap bolts and side bolts to
make the rearmost main bearing be lightly seated.
Measure the crankshaft end play in this condition.
Tightening Sequence of Main Bearing Cap Bolts
Main bearing cap bolt - Install
Be sure to observe the specified tightening sequence
when tightening the main bearing cap bolts and side
bolts.
Main bearing cap
1
2
3
4
First time:
Main bolt
1, 2: 294 ± 15 N·m
{30 ± 1.5 kgf·m}
[217 ± 11.1 lbf·ft]
Side bolt 3, 4 : 74 ± 3.7 N·m
{7.5 ± 0.38 kgf·m}
[54.6 ± 2.73 lbf·ft]
Second time:
Main bolt
1, 2: 588 ± 29 N·m
{60 ± 3.0 kgf·m}
[434 ± 21.7 lbf·ft]
Side bolt 3, 4 : 147 ± 7.4 N·m
{15 ± 0.75 kgf·m}
[108.4 ± 5.46 lbf·ft]
Tighten to the specified
torque in the numerical
order in two steps.
[Wet]
Bottom
Top
Right
Left
View from engine rear side
Side bolt Side bolt
147
147 ± ± 7.4 N 7.4 N·m
{15 {15 ± ± 0.75 kgf 0.75 kgf·m} m}
[108 [108 ± ± 5.4 lbf 5.4 lbf·ft] ft]
[Wet] [Wet]
Main bolt
588 ± 29.4 N·m
{60 ± 3.0 kgf·m}
[434 ± 21.7 lbf·ft]
[Wet]
Side bolt
147 ± 7.4 N·m
{15 ± 0.75 kgf·m}
[108 ± 5.4 lbf·ft]
[Wet]