Crankshaft Main Bearing Replacement
Crankshaft Main Bearing Replacement
Main Bearing Clearance Inspection
| 1. | To check main bearing-to-journal oil clearance, remove the lower block and bearing halves. |
| 2. | Clean each main journal and bearing half with a clean shop towel. |
| 3. | Place one strip of plastigage across each main journal. |
| 4. | Reinstall the bearings and lower block, then torque the bolts to 29 N·m (3.0 kgf·m, 22 lbf·ft)+56°. NOTE: Do not rotate the crankshaft during inspection. |
| 5. | Remove the lower block and bearings again, and measure the widest part of the plastigage.
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| 6. | If the plastigage measures too wide or too narrow, remove the crankshaft, and remove the upper half of the bearing. Install a new, complete bearing with the same color code(s), and recheck the clearance. Do not file, shim, or scrape the bearings or the caps to adjust clearance. |
| 7. | If the plastigage shows the clearance is still incorrect, try the next larger or smaller bearing (the color listed above or below that one), and check again. If the proper clearance cannot be obtained by using the appropriate larger or smaller bearings, replace the crankshaft and start over. |
Main Bearing Selection
Crankshaft Bore Code Location
| 1. | Numbers or letters or bars have been stamped on the end of the block as a code for the size of each of the five main journal bores. Write down the crank bore codes. If you can't read the codes because of accumulated dirt and dust, do not scrub them with a wire brush or scraper. Clean them only with solvent or detergent.  No.1 JOURNAL(PULLEY END)No.5 JOURNAL (TRANSMISSION END) |
Main Journal Code Location
| 2. | The main journal codes are stamped on the crankshaft.  No. 1 JOURNALNo. 5 JOURNAL |
| 3. | Use the crank bore codes and crank journal codes to select the appropriate replacement bearings from the following table. NOTE:
K20A6 engine:  Larger crank bore1 or A or I2 or B or II3 or C or III4 or D or IIIISmaller bearing (Thicker)BluePinkYellowGreenGreen/ BrownBrownGreenGreen/ BrownBrownGreenGreen/ BrownBrownGreenGreen/ BrownBrownBlackBlack/ BlueCrank bore codeMain journal code123456Smaller main journalSmaller bearing (Thicker)Pink/ YellowYellowYellowPink/ YellowBlackBlackBlack/ Blue K24A3 engine:  Larger crank bore1 or A or I2 or B or II3 or C or III4 or D or IIIISmaller bearing (Thicker)BlackRedPinkYellowYellow/ GreenGreenYellowYellow/ GreenGreenYellowBrownCrank bore codeMain journal code123456Smaller main journalSmaller bearing (Thicker)PinkRed/ PinkBrownBrown/ BlackRed/ PinkPinkYellowYellow/ GreenGreenBrownYellow/ GreenGreenBrown/ Black |