Connecting Rod and Bearings

WARNING: This page is about a different variant/trim than selected.

IMPORTANT:

The powdered metal connecting rod and cap are machined for proper clearances. The connecting rod and cap must be used as an assembly with no repair or modifications to either mating surface. Do not attempt to repair the rod or cap. If service is required, replace the first design press-fit piston, pin, and connecting rod as an assembly.
Do not attempt to repair the bolt hole threads of the connecting rod.

Fig 1: View Of Piston & Connecting Rod Components

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CAUTION: Wear safety glasses in order to avoid eye damage.

Fig 2: Identifying Connecting Rod Inspection Areas

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Inspect the connecting rod for the following conditions:
- Twisting (1)
- Proper fit of the connecting rod and cap mating surfaces (2)
- Nicks or gouges in the bearing bore (3)
- Damage to the bearing locating slots (4)

Fig 3: View Of Connecting Rod Bearing Bore

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Measure the connecting rod bearing bore (1) for an out-of-round condition. Refer to Engine Mechanical Specifications (LS6) .

Fig 4: Measuring Piston Pin Diameter

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To determine piston pin-to-connecting rod bore clearance, use a micrometer and measure the piston pin outside diameter (OD).

Fig 5: Measuring Connecting Rod Pin Bore Inside Diameter

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To determine piston pin-to-connecting rod bore clearance, use a micrometer and measure the connecting rod pin bore (1) inside diameter (ID).
Subtract the piston pin OD measurement from the connecting rod pin bore ID measurement to determine pin-to-bore clearance. Refer to Engine Mechanical Specifications (LS6) .

Fig 6: Identifying Crankshaft Bearing Craters Or Pockets

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Inspect the connecting rod bearings for craters or pockets. Flattened sections on the bearing halves indicate fatigue.

Fig 7: Identifying Connecting Rod Bearing Scoring Or Discoloration

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Inspect the connecting rod bearings for excessive scoring or discoloration.
Inspect the connecting rod bearings for dirt or debris imbedded into the bearing material.

Fig 8: Crankshaft Bearing Polished Sections (Improper Seating)

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Inspect the connecting rod bearings for improper seating indicated by bright, polished sections of the bearing surface.