Crankshaft and Bearing Cleaning and Inspection
Special Tools
• | EN-45059 Torque Angle Sensor Kit |
For equivalent regional tools, refer to Special Tools .
Cleaning Procedure
- Clean the following components in solvent:
• | Connecting rod bearings |
• | Crankshaft oil passages |
• | Crankshaft threaded holes |
Warning: Refer to Safety Glasses and Compressed Air Warning in the Preface section.
- Dry the following components with compressed air:
• | Connecting rod bearings |
• | Crankshaft oil passages |
• | Crankshaft threaded holes |
Visual Inspection
- Perform the following visual inspections:
• | Inspect the crankshaft balancer bolt hole (1) for thread damage. |
• | Inspect the crankshaft keyway (3) for damage. |
• | Inspect the oil pump drive flats (4) for damage. |
• | Inspect the crankshaft main journals (5) for damage. |
• | Inspect the crankshaft connecting rod journals (6) for damage. |
• | Inspect the crankshaft oil passages (7) for obstructions. |
• | Inspect the crankshaft main bearing thrust wall surfaces (8) for damage. |
• | Inspect the crankshaft counterweights (9) for damage. |
• | Inspect the crankshaft position sensor inner excitor ring (10) for damage. |
• | Inspect the crankshaft rear main oil seal surface (11) for damage. |
• | Inspect the crankshaft engine flywheel mounting surface (12) for damage. |
• | Inspect the crankshaft pilot hole (13) for damage. |
• | Inspect the crankshaft engine flywheel bolt holes (14) for thread damage. |
- Repair or replace the crankshaft as necessary.
Crankshaft and Bearing Inspection
- Inspect for fatigue indicated by craters or pockets. Flattened sections on the bearing halves also indicate fatigue.
- Inspect for excessive scoring or discoloration on both front and back of the bearing halves.
- Inspect the main bearings for dirt embedded into the bearing material.
- Inspect for improper seating indicated by bright, polished sections.
Crankshaft End Play, Check
Note : Crankshaft (2) attached with crankshaft bearing caps.
- Install the GE-49449 gauge (1)
• | Install in the holder on the front of the engine block. |
• | Place the dial gauge plunger (1) against the crankshaft and adjust. |
- Measure the longitudinal play of the crankshaft.
• | Move the crankshaft in the longitudinal direction. |
• | Permissible crankshaft end play: 0.09-0.35 mm (0.0036-0.0138 in). |
- Remove the GE-49449 gauge .
Crankshaft Out-of-Round, Check
Note: Crankshaft removed.
- Insert the crankshaft in the engine block.
- Install the GE-49449 gauge
• | Attach to the bracket on the engine block. |
• | Place the dial gauge plunger against the crankshaft bearing journal and adjust. |
- Check the rotational play of the crankshaft.
• | Turn the crankshaft evenly. |
• | Maximum permissible rotational play: 0.03 mm (0.0012 in). |
- Remove the GE-49449 gauge .
Check Crankshaft Bearing Clearance (With Plastigage)
- Lay on a suitable plastigage.
Lay out Plastigage (flexible plastic thread) around the entire width of the con-rod bearing journal (arrow).
- Install the lower crankcase (1).
Caution: Refer to Fastener Caution in the Preface section.
- Install the 10 lower crankcase bolts (1) in a sequence as in the graphic shown and tighten in three passes:
3.1. | First pass in sequence to 25 N·m (19 lb ft). |
3.2. | Second pass in sequence to an additional 45 degrees using the EN-45059 angle sensor . |
3.3. | Third pass in sequence to an additional 90 degrees using the EN-45059 angle sensor . |
Note: Do not rotate the crankshaft.
- Remove the 10 lower crankcase bolts in a sequence as in the graphic shown.
- Remove the lower crankcase (1).
Note: When reading the value, do not confuse millimeters and inches on the measuring scale.
- Measure the crankshaft bearing play.
• | Compare the width of the flattened plastic thread (arrow) to the measuring scale. |
• | Permissible crankshaft bearing play: 0.02-0.04 mm (0.001-0.003 in). |
Check Crankshaft Bearing Clearance (With Micrometer Gauge Internal Measuring Device)
Caution: Refer to Fastener Caution in the Preface section.
Note:
• | Consider the correct tightening sequence. |
- Install the lower crankcase with the crankshaft bearings to the engine block.
Caution: Refer to Fastener Caution in the Preface section.
- Install the lower crankcase (1).
- Install the 10 lower crankcase bolts (1) in a sequence as in the graphic shown and tighten in three passes:
2.1. | First pass in sequence to 25 N·m (19 lb ft). |
2.2. | Second pass in sequence to an additional 45 degrees using the EN-45059 angle sensor . |
2.3. | Third pass in sequence to an additional 90 degrees using the EN-45059 angle sensor . |
- Install the inner plunger and calibrate with the micrometer gauge (1).
- Measure the crankshaft bearing diameter at 3 points.
Measure at points I, II and III with the internal measuring device.
Calculate the average crankshaft bearing diameter.
Formula: A+ B+ C /3.
- Measure the crankshaft bearing journal diameter at 2 points.
Measure at points I and II with the micrometer gauge.
- Calculate the average crankshaft bearing journal diameter.
Formula: I + II/2.
- Determine the crankshaft bearing play.
Calculation formula: average crankshaft bearing diameter minus average crankshaft bearing journal diameter.
- Nominal-Actual comparison.
Permissible crankshaft bearing play: 0.02-0.04 mm (0.001-0.003 in).
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