Installation and Measuring Crankshaft Bearing Clearance

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NOTE:
- Crankshaft bearing clearances are critical. Excessive crankshaft bearing clearance may affect crankshaft position (CKP) sensor signals and/or on-board diagnostic (OBD) II system performance.
- Crankshaft bearing caps must be installed to the proper location and direction.
- When installing the crankshaft bearings, align the locating tabs on the bearings with the locating notches in the engine block journal bore and the bearing cap.
- Always install crankshaft bearings with their machined partner. Do not file bearings or mix bearing halves.
- In order to prevent engine block oil leakage, install NEW crankshaft bearing cap side bolts.
Install the crankshaft bearings (2 and 5) to the engine block and bearing caps (1). The thrust bearings (6) are to be installed into center journal.
Lubricate the bearing surfaces and crankshaft journals with clean engine oil.

CAUTION:

To maintain proper crankshaft end play, use extreme care during crankshaft installation. Avoid scoring or damaging the thrust bearing.

Install the crankshaft (3).
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Ensure the bearing caps (1) are installed correctly.

The bearing caps must be installed in the proper location and direction. The arrows on the bearing caps must point toward front of engine.
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CAUTION:
This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component.

NOTE:
The inner bearing cap bolts are longer than the outer bearing cap bolts.

Install NEW inner bearing cap bolts (1) and NEW outer bearing cap bolts (2) and hand tighten.
Using a plastic-face hammer, tap the bearing caps into place.
Install the NEW bearing cap side bolts (3) and hand tighten.
Tighten the inner bearing cap bolts in sequence. Fastener Specifications

NOTE:

To properly align the crankshaft thrust bearings, the final thrust of the crankshaft MUST be in the forward direction.

Using a plastic-face hammer, tap the crankshaft rearward, then forward in order to align the thrust bearings.
Tighten the outer bearing cap bolts in sequence. Fastener Specifications
Tighten the main bearing cap side bolts in sequence. Fastener Specifications
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Install the crankshaft position sensor (2). Rotate the sensor until the locating hole in the bracket aligns with the bolt hole in the block.
Install and tighten the sensor bolt (1). Fastener Specifications
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Measure the crankshaft end play.
1. Thrust the crankshaft forward or rearward.
2. Mount a dial indicator gauge with the tip engaging the front face of the nose of the crankshaft.
3. Thrust the crankshaft in the opposite direction as step 12.1. Record the measurement from the dial indicator.
  Compare the measurement to the required end play specification. Engine Mechanical Specifications (L84) , or Engine Mechanical Specifications (L87)
4. If the bearing clearance is not within specifications, inspect the thrust surfaces for nicks, gouges or raised metal. Minor imperfections may be removed with a fine stone.
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NOTE:
Measurements of all components should be taken with the components at normal room temperature. For proper piston fit, the engine block cylinder bores must not have excessive wear or taper. A used piston, pin, and connecting rod assembly may be installed if, after inspection is within specifications.

With a micrometer (2) at a right angle, measure the piston (1) outside diameter (OD). Measure the diameter 43 mm (1.69 in) from the top of the piston. Engine Mechanical Specifications (L84) , or Engine Mechanical Specifications (L87)
Record the piston OD.
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Adjust the micrometer to the recorded piston OD.
Insert the EN-8087 Cylinder Bore Gauge into the micrometer and zero the gauge dial.
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Using the EN-8087 Cylinder Bore Gauge (1), measure the cylinder bore inside diameter (ID). Measure at a point 64 mm (2.5 in) from the top of the cylinder.
Record the cylinder bore ID.
Subtract the piston OD from the cylinder bore ID in order to determine the piston-to-bore clearance. Engine Mechanical Specifications (L84) , or Engine Mechanical Specifications (L87)
If the proper clearance cannot be obtained, select another piston and pin assembly and measure the clearances again. If the proper fit cannot be obtained, the cylinder bore may require honing for an oversize piston.