CRANKSHAFT, PISTON AND CONNECTING ROD
72
Connecting rod inspection
1. Inspect the connecting rod for cracks or any
signs of damage.
2. Install the rod cap and tighten to a torque of 106
-124 in-lbs (12 - 14Nm).
3. Measure the inside diameter of the connecting
rod at both ends and compare the measure
-
ments to those listed in the chart at the end of
this chapter.
See Figure 10.15.
NOTE: Take two measurements 90 degrees
apart. This will check the roundness of the con
-
necting rod bearing surfaces.
NOTE: Connecting rods are not available as ser-
vice parts. If the connecting rod is bad, the
engine must be short blocked.
4. Take the crank pin and piston pin measure-
ments and subtract them from the connecting
rod measurements to get the connecting rod to
journal running clearance and the piston pin to
connecting rod running clearance. Compare that
number to the one listed in the chart at the end
of this chapter.
NOTE: Plasti-gauge can be used to measure the
connecting rod to journal running clearance, but
it is very technique sensitive and it is not as reli
-
able as the method described above.
Cylinder inspection
1. Clean and inspect the cylinder, inside and out.
NOTE: If there is any sign of damage, especially
cracked cooling fins, short block the engine.
NOTE: Take two measurements of the cylinder
bore 90 degrees apart at the top, bottom and
middle of the cylinder.
See Figure 10.16.
NOTE: The measurements can be made using
telescoping gauges, inside micrometers or dial
indicating bore gauge.
2. Compare the measurements to those that are
listed in the chart at the end of the chapter.
• The bore should not be worn too large
• The bore should not be tapered.
• The bore should be round, not oval shaped.
3. Inspect the cylinder cross hatch.
NOTE: The cross hatch is important because it
helps hold oil on the cylinder walls.
NOTE: If the cross hatch is polished off, that is a
sign of dirt ingestion. The cylinder can not be re-
honed because replacement piston rings are not
available. The engine must be short blocked.
Figure 10.15
Measure at
right angles
Measure at
right angles
Figure 10.16
Measure the cylinder bore
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