TM 9-4310-397-14
(g)
Compare measurements with the following specifications:
Connecting Rod Specifications
Crankshaft Journal OD ...........................2.748 - 2.749 in.(69.80 - 69.82 mm)
Assembled Rod Bearing ID .......................2.750 - 2.72 in.(69.85 - 69.90 mm)
Oil Clearance (new parts)..........................0.0012 - 0.004 in.(0.03 - 0.10 mm)
Maximum Serviceable Clearance 0.0062 in ..................................(0.16 mm)
(h)
Inspect connecting rod bearings for wear or damage. If bearings are worn or are out of specification,
replace both connecting rod bearings.
(4)
Inspect rod and cap.
(a)
Inspect rod and cap for wear or damage, such as chips or cracks in the joint area.
(b)
Inspect in and around cap screw holes in cap. If any defects are found, replace rod and cap.
(c)
Carefully clamp rod in a soft-jawed vise (cap end upward).
(d)
Install cap without bearing inserts.
(e)
Torque cap screws to 55 ft-lb (75 Nm).
(f)
Using an inside micrometer, measure rod bore at center of bore and record measurements as follows:
1
At right angle to rod/cap joint.
2
At 45 degrees left of measurement step 1.
3
At 45 degrees right of measurement step 1.
4
Rod Bore ID Specification 2.900 - 2.901 in. (73.66 - 73.96 mm)
(g)
Compare the measurements. If difference between the greatest and least measurement is more than
0.0015 in. (0.038 mm), the rod and cap are out of round. Replace both connecting rod and cap.
(5)
Inspect piston pins and bushings.
(a)
Visually inspect piston pin for general overall condition. Pin must be replaced if it shows signs of fretting.
Piston pin has a highly polished surface. Do not attempt to polish or refinish.
(b)
Measure OD of pin. Replace if not within specifications:
Piston Pin Specifications
Small pin ...............................................1.374 - 1.375 in.(34.92 - 34.93 mm)
Large pin ..................................................1.624 - 1.625 in.(41.27 - 4.28 mm)
Wear Tolerance .............................................................. 0.005 in. (0.13 mm)
(c)
Inspect piston pin bushing for damage or excessive wear. Lubrication hole must be open.
(d)
Compare pin bushing ID with pin for specified clearance.
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