Main Bearings Inspection - Suzuki Swift Sport 2004 Service & Repair Manual

1D-59 Engine Mechanical:

Main Bearings Inspection

General Information
• Service main bearings are available in standard size
and 0.25 mm (0.0098 in.) undersize, and each of them
has 5 kinds of bearings differing in tolerance.
• Upper half of bearing (1) has oil groove (2) as shown
in figure.
Install this half with oil groove to cylinder block.
• Lower half of bearing does not have an oil groove.
Visual Inspection
Check bearings for pitting, scratches, wear or damage.
If any malcondition is found, replace both upper and
lower halves. Never replace either half without replacing
the other half.
Main Bearing Clearance
NOTE
Do not rotate crankshaft while gauging
plastic is installed.
Check clearance by using gauging plastic according to
the following procedure.
1) Remove bearing caps.
2) Clean bearings and main journals.
3) Place a piece of gauging plastic (1) the full width of
bearing (parallel to crankshaft) on journal, avoiding
oil hole.
4) Tighten main bearing cap No.1 bolts (a) and main
S7RS0B1406038 bearing cap No.2 bolts (b) gradually as follows.
a) Tighten bolts ("1" through "10") to 30 N⋅m (3.0
kgf-m, 22.0 lb-ft) according to numerical order in
the figure.
b) In the same manner as in Step a), tighten them
to 50 N⋅m (5.0 kgf-m, 36.5 lb-ft).
c) In the same manner as in Step a), retighten them
to 60°.
d) Tighten bolts ("11" through "18") to 25 N⋅m (2.5
kgf-m, 18.0 lb-ft) according to numerical order in
the figure.
Tightening torque
Main bearing cap No.1 bolt (a): 30 Nm (3.0
kgf-m, 22.0 lb-ft), 50 Nm (5.0 kgf-m, 36.5 lb-ft)
and then retighten by turning through 60°
Main bearing cap No.2 bolt (b): 25 N·m (2.5
kgf-m, 18.0 lb-ft)
I2RH0B140139-01
5) Remove bearing caps and using scale (1) on
gauging plastic envelop (2), measure gauging plastic
width at its widest point. If clearance exceeds its
limit, replace bearing. Always replace both upper
and lower inserts as a unit.
A new standard bearing may produce proper
clearance. If not, it will be necessary to regrind
crankshaft journal for use of 0.25 mm undersize
bearing.
After selecting new bearing, recheck clearance.
Main bearing clearance
Standard: 0.021 – 0.041 mm (0.0008 – 0.0016 in.)
Limit: 0.054 mm (0.0021 in.)
I2RH0B140140-01
I6RS0C140027-01
I2RH0B140141-01