N14 Base Engine Troubleshooting and Repair Manual – 001-005   Bearings, Connecting Rod

WARNING  Some state and federal agencies have determined that used engine oil can be carcinogenic and cause reproductive toxicity. Avoid inhalation of vapors, ingestion, and prolonged contact with used engine oil. If not reused, dispose of in accordance with local environmental regulations.

• Drain the lubricating oil. Refer to Procedure 007-025.
• Remove the lubricating oil pan. Refer to Procedure 007-025.

Rotate the crankshaft to position two of the connecting rods at bottom dead center (BDC).

Use the accessory drive pulley to rotate the crankshaft.

Loosen the connecting rod capscrews.

Do not remove the capscrews.

Hit the connecting rod capscrews with a rubber hammer to loosen the rod caps from the dowels.

Remove the capscrews and the rod cap.

Remove the bearing shell from the rod cap, and mark the cylinder number and the letter “L” in the flat surface of the bearing tangs.

After installing two guide pins, Part Number 3375601, in the connecting rod, push the rod up far enough to allow the upper bearing shell to be removed. Use a dead blow mallet to push the rod away from the crankshaft.

NOTE: The mallet must be wood or plastic. Do not pound or strike the rod or bearings. Use the mallet only to push the rod.

Remove the bearing shell, and mark the cylinder number and the letter “U” in the flat surface of the bearing tangs.

WARNING  When using a steam cleaner, wear safety glasses or a face shield, as well as protective clothing. Hot steam can cause serious personal injury.

WARNING  Wear appropriate eye and face protection when using compressed air. Flying debris and dirt can cause personal injury.

Steam clean the parts, and dry with compressed air.

NOTE: Refer to Parts Reuse Guidelines, Bulletin 3810303, for information on bearing inspection.

• Inspect the rod caps, connecting rod bearing saddles, and capscrews for nicks, cracks, burrs, scratches, or fretting.

• Inspect the bearings for damage.

Replace any bearings with lock tang damage or scratches (deep enough to be felt with a fingernail). Also replace any bearings which show pitting, flaking, or corrosion in the copper lining.

NOTE: Normal bearing wear produces a smooth finish which will wear into the copper lining. Exposed copper does not always indicate worn bearings. If large areas of copper lining are visible in the bearings before the engine has accumulated 240,000 kilometers [150,000 miles] or 3,750 hours, inspect the engine for contamination from fine dirt particles and correct the problem.

• Inspect the bearing seating surface for nicks or burrs.
• If nicks or burrs can not be removed with a fine crocus cloth, the bearings must be replaced.

NOTE: For more detailed information of bearing damage, refer to Analysis and Prevention of Bearing Failures, Bulletin 3810387.

• Measure the rod bearing shell thickness with an outside micrometer that has a ball tip.

• Discard a bearing shell if its thickness is below the minimum specification.

NOTE: Bearing shells are available for crankshafts which are 0.25 mm [0.010 in], 0.51 mm [0.020 in], 0.76 mm [0.030 in], or 1.02 mm [0.040 in] undersize. Crankshafts which are ground undersize in the connecting rod or the main bearing journals are marked on the front counter weight. If the crankshaft is marked, check the bearing shell part number to make sure the correct bearing size is used.

CAUTION  The connecting rod and bearing shell mating surfaces must be clean and dry when the bearing shells are installed. Used bearings must be installed in their original location.

Use Lubriplate® 105, or equivalent, to lubricate the crankshaft journal mating surface of the upper bearing shell.

Install the upper bearing shell into the connecting rod with the tang of the bearing in the slot of the rod.

Install the bearing shell into the connecting rod cap with the tang (2) of the bearing in the slot (1) of the cap.

Use Lubriplate® 105, or equivalent, to lubricate the bearing shell to crankshaft journal mating surface and the connecting rod capscrews.

CAUTION  The rod cap alpha characters must match the alpha characters on the connecting rod and must be installed with the characters aligned to prevent damage to the connecting rods and crankshaft. The locking tang of the connecting rod cap must be toward the camshaft side of the cylinder block.

CAUTION  Rod and cap mating surfaces must be clean.

Install the cap onto the connecting rod.

Tighten the connecting rod capscrews in alternating sequence. Refer to Torque Plus Turn in Procedure 001-047.

Measure the connecting rod side clearance. Refer to Procedure 001-054.

Repeat installation steps above, and install the remaining bearing shells and connecting rod caps.

CAUTION  The lubricating oil system must be primed before operating the engine after any internal engine repairs, to reduce the possibility of internal component damage.

• Install the lubricating oil pan. Refer to Procedure 007-025.
• Prime the lubricating system. Refer to Procedure 007-037.
• Fill the lubricating oil pan. Refer to Procedure 007-025.
• Operate the engine until it reaches a temperature of 82°C [180°F], and check for lubricating oil leaks.