GMC C Series 1993, Руководство по ремонту

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5J-6 AIR COMPRESSOR AND GOVERNOR
Figure 10-—Measuring the Connecting Rod Journal
— Standard crankshaft connecting rod journals
are 1.1242 to 1.1252 inch in diameter. If the,
crankshaft journals are scored, worn, or
out-of-round and cannot be reground,
replace the crankshaft.
— Use 0.010, 0.020, or 0.030 inch undersize
connecting rod bearing inserts. , !
— Maintain a 0.005 inch clearance between
the main bearing and the main bearing,
crankshaft journals. -
• Clean oil passages. '
5. Cylinder bores. ; ■ . "
•Grooved walls must be square and have a
good finish. !
•U se an inside micfometer or caliper to checK
cylinder bores (figure .11).
•R e-bore or hone cylinder bores scored or
out-of-round more than 0.0005 inch or tapered
more than 0.0005 inch. :
— Replace pistons with 0.01.0, 0.020, and
0;030 inch oversize pistons and rings.
• Finish the cylinder bores to a smooth .
cross-hatch surface.
• Maintain a 0.002 to 0.004 inch clearance
■ between the piston and cylinder bore (figure
12). , . ; ;
■;;*r ■ - ■ V
Figure 11— Measuring the Cylinder Bore
Figure 12—Checking the Piston to Cylinder Fit
6. Connecting rod bearing (34).
• Replace used bearing inserts.
-r- Do not interchange connecting rod caps.
• Position the locking slots of the connecting rod
and cap next to each other. •
• Maintain a 0.0003 to 0.0021 inch clearance
between the connecting rod journal and the
connecting rod bearing after assembling.
N O T IC E : S e e “N o tic e ” o n p a g e 5 J -1 .
7.
Check the clearance, using plastic gaging material
(figure 13).
A. Install the bearing inserts into the connecting
• < • rods.
B. Clean the crankshaft journals to remove oil.
| 9 | Important
• The gaging material is soluble in oil.. The
journals must be dry to give an accurate
reading. .
C. Place gaging material on the lower half of the
bearings. ;
A. Width Before Gaging
B. Width After Gaging
C. Plastigage Scale B6091
Figure 13— Measuring the Bearing Clearance