GMC 1990 Light Truck Repair Manual page 373

Figure 39—Placing the Gaging Plastic on the
Connecting Rod Journal
sively out-of-round, interference between the
bearing and the crankpin will result in rapid
bearing failure.
3. Connecting rod cap with the lower connecting rod
bearing insert. DO NOT TURN THE CRANKSHAFT
WITH THE GAGING PLASTIC INSTALLED.
4. Connecting rod cap nuts.
& Tighten
Nuts to " Specifications." Refer to the proper
section.
Important
The gaging plastic will be found sticking either to
the journal or lower connecting rod bearing insert.
Do not remove it at this time.
GENERAL ENGINE MECHANICAL 6A-21
A. Measure W idest Point o f Gaging
Plastic w ith Graduated Scale
Figure 40—Measuring the Gaging Plastic
Measure (Figure 40)
Gaging plastic at its widest point, using the scale at
the gaging plastic envelope (figure 40).
If the clearance exceeds specifictions, select a new,
correct size, connecting rod bearing and remeasure
the clearance.
A standard or undersize bearing mayt produce the
proper clearance. Refer to the proper section for
bearing availability.
Do not attempt to use shims or file the bearing to
obtain the needed clearance.
If clearance cannot be brought to within specifica­
tions, recondition or replace the crankshaft. (Do not
recondition a rolled fillet crankshaft, such as used
on 2.5 L, 2.8 L, and 6.2 L engines.)
+ + Remove or Disconnect
Gaging plastic.
B-04997