Cummins N14 STC, Celect, Celect Plus – Service Manual 001-016   Crankshaft

Use a lint free cloth to clean the crankshaft bearing journals.

WARNING  This component or assembly weighs greater than 23 kg [50 lb]. To prevent serious personal injury, be sure to have assistance or use appropriate lifting equipment to lift this component or assembly.

CAUTION  Use a lifting strap that will not damage the crankshaft. Do not drop the crankshaft on the bearings.

The end of the crankshaft with the smallest diameter must point toward the front of the block. Install the crankshaft.

Use a lint free cloth to clean the thrust bearings, the main bearing shells, and the main bearing caps.

NOTE: If used thrust bearings are to be installed, each must be installed in its original location in the engine. The bearing journal numbers must have been marked on the bearing during disassembly.

Use clean Lubriplate™ 105, or equivalent, to lubricate the upper thrust bearings.

CAUTION  The grooves must be toward the crankshaft.

Install the upper thrust bearings in the number 7 main bearing saddle.

NOTE: Push the crankshaft toward the rear of the engine to install the front bearing and to the front of the engine to install the rear bearing.

The end of the thrust bearing must be even with the main bearing cap mounting surface.

Install the dowel ring in the dowel ring counterbore of the cylinder block.

Install the lower main bearing shells as follows:

• Use clean Lubriplate™ 105, or equivalent, to lubricate the bearing shell to the crankshaft journal mating surface.

Align the dowel ring groove in the bearing with the dowel ring.

The dowel ring grooves (1) and (2) in the bearings must be engaged with the dowel ring (3).

Push on the side of the bearing shell opposite the dowel ring to install the bearing shell.

The end of the lower main bearing shell opposite the dowel ring must be engaged between the crankshaft and the cylinder block and be seated against the end of the upper bearing shell.

NOTE: If installed correctly, the ends of the bearing shells (1) will meet approximately 1.50 mm [0.060 in] below the cylinder block main bearing mounting surface.

NOTE: If used thrust bearings are to be installed, each must be installed in its original location in the engine. The bearing journal numbers must have been marked on the bearing during disassembly.

Use Lubriplate® 105, or equivalent, to lubricate the lower thrust bearings.

Place the lower thrust bearings around the number 7 main journal with the grooves facing the thrust surface on the crankshaft.

NOTE: The notch (1) on the outside diameter of the lower thrust bearings must align with the locating pins in the number 7 main bearing cap.

CAUTION  Drain the excess oil from the capscrews before installing them in the cylinder block to prevent hydraulic lock and possible damage to the cylinder block during the capscrew torquing operation.

Use clean 15W-40 oil to lubricate the capscrew threads and flat washers.

CAUTION  The main bearing caps are marked for position (1) on the camshaft side and the cylinder block identification (2) on the exhaust side. The cylinder block identification number (3) is stamped on the pan rail on the camshaft side of the block. Install the caps in the correct position with the position number to the camshaft side and its part number toward the rear of the engine.

Install the main bearing caps as follows:

• Align the capscrew holes in the cap with the holes in the cylinder block. Make sure the dowel ring and lower bearing shell are in position.

• Install the capscrews and the washers through the cap and into the cylinder block.
• Hand tighten the capscrews two to three threads.

CAUTION  Do not use impact wrenches. The main bearing shells can become dislocated.

Use both of the capscrews to pull the main bearing cap into position.

Use two wrenches. Tighten both of the capscrews at the same time.

Make sure the cap is touching the block. If it is not, check for a bearing out-of-location.

CAUTION  Do not rotate the crankshaft until the main bearing capscrews are tightened. This will keep the bearings in place.

Tighten the main bearing capscrews in the sequence illustrated.

Tighten the main bearing capscrews on engines built with 1-inch diameter main bearing capscrews to the following torque values:

1. Loosen completely.
2. Repeat steps 1 through 3.

Tighten the main bearing capscrews on engines built with ¾-inch diameter main bearing capscrews to the following torque values:

1. Loosen completely.
2. Repeat steps 1 through 3.

Turn the crankshaft by hand. If it does not turn freely, loosen the main bearing capscrews one cap at a time. This will help locate the bearing that is too tight.

Remove the main bearing cap and the bearing. Check for an incorrect or mislocated bearing or main bearing cap, for incorrect oversize bearing, or debris between the main bearing and the cap.

Tighten the main bearing capscrews in the sequence illustrated and to the torque values shown above.

Measure the end clearance of the crankshaft as follows:

1. Install a dial indicator to the rear face of the cylinder block.
2. Place the tip of the gauge against the end of the crankshaft.
3. Push the crankshaft toward the rear of the cylinder block.

1. Set the dial indicator to “0”.
2. Push the crankshaft toward the front of the cylinder block.
3. If the end clearance is less than 0.18 mm [0.007 in], do the following:

• Loosen the main bearing capscrew one turn.
• Push the crankshaft toward the front and then toward the rear of the cylinder block.

• Tighten the main bearing capscrews in the sequence shown in the illustration.

Measure the crankshaft end clearance. The end clearance specification for a new or reground crankshaft with new thrust bearings is 0.18 mm [0.007 in] to 0.45 mm [0.018 in].

NOTE: Crankshafts that have been reground on the thrust bearing surfaces are marked for oversize thrust bearings on the rear crankshaft counter weight. If the crankshaft counter weight is marked, check the thrust ring part number to make sure the correct thrust ring size is used.

Example: F. – .010 = Front 0.25 mm [0.010 in]

Example: R. – .020 = Front 0.51 mm [0.020 in]

If the crankshaft end clearance is more than 0.56 mm [0.022 in], use oversize thrust bearings to adjust the end clearance to the correct specification.