Measuring Clearance Between Main Bearing And Crankshaft Journal - Mitsubishi L Series Service Manual

4.9 Measuring clearance between main bear-
ing and crankshaft journal
(a) When grinding crank journals, be sure to grind all
the journals to the same size.
(b) Finish the fillet radius to the specified dimension.
(1) Reassemble main bearings.
(2) Tighten the main bearing caps to the specified torque.
(3) Measure the inside diameter of the main bearings.
(4) Measure the outside diameter of the crank journal.
(5) Calculate the clearance between the inside diameter of
the main bearing and outside diameter of the crank
journal.
(6) Replace the main bearing if the clearance exceeds the
limit.
(7) Measure the clearance between the main bearing cap
and the crank journal again. Use the undersize bearing
if the limit is exceeded.
(8) If an undersize bearing is used, grind the crank journal
to the specified undersize.
Item Nominal
Outside diameter of
ø 43 mm
crankshaft journal
[1.69 in.]
(STD)
Clearance between
main bearing and –
crankshaft journal
Undersize grinding dimensions of crankshaft
Item Undersize
0.25 mm
[0.0098 in.]
Crank journal
undersize
0.50 mm
[0.0197 in.]
Standard Limit
42.965 to 42.980 mm
–
[1.6915 to 1.6921 in.]
0.030 to 0.075 mm 0.10 mm
[0.0012 to 0.0030 in.] [0.0039 in.]
Finish dimension
-0.020
ø 42.75 mm
-0.035
-0.0008
[1.6831 in.]
-0.0014
-0.020
ø 42.50 mm
-0.035
-0.0008
[1.6732 in.]
-0.0014
INSPECTION AND REPAIR OF BASIC ENGINE
Tightening torque
49.0 to 53.9 N m
{5.0 to 5.5 kgf m}
[36.2 to 39.8 lbf ft]
Measuring main bearing fitting bore
Measuring
Measuring
directions
points
Measuring crank journal outside diameter
0
R2 mm
-0.2
0
[0.08 in.]
-0.008
Finish dimension of fillet radius
Measuring Measuring
directions points
0
R2 mm
-0.2
0
[0.08 in.]
-0.008
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