Crankshaft Main Bearing
Main Bearing Clearance Inspection1. To check main bearing-to-journal oil clearance, remove the main caps 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.
NOTE: If the engine is still in the car when you bolt the main cap down to check clearance, the weight of the crankshaft and flywheel will flatten the plastigage further than just the torque on the cap bolt and give you an incorrect reading. For an accurate reading, support the crank with a jack under the counterweights, and check only one bearing at a time.
4. Reinstall the bearings and caps, then torque the bolts to 25 Nm (2.5 kgf-m, 18 ft. lbs.) + 60°.
NOTE: Do not rotate the crankshaft during inspection.
5. Remove the caps and bearings again, and measure the widest part of the plastigage.
6. If the plastigage measures too wide or too narrow, remove the upper half of the bearing. Install a new, complete bearing with the same color coders), 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.
Crankshaft Bore Code Location
Crankshaft Bore Code Location:
1. Letters have been stamped on the end of the block as a code for the size of each of the 4 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.
Main Journal Code Locations:
2. The main journal codes are stamped on the No. 1 web.
3. Use the crank bore codes and crank journal codes to select the appropriate replacement bearings from the table.
NOTE:
- Color code is on the edge of the bearing.
- When using bearing halves of different colors, it does not matter which color is used in the top or bottom.