Clearance

Clearance

1. 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 cloth towel.

A Plastigage Strip

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 75Nm.

Note: Do not rotate the crankshaft during inspection.

5. Remove the cap and bearings again, and measure the widest part of the plastigage.

Main Bearing – to – journal Oil Clearance:
No. 1, 2 (New): 0.021 – 0.045 mm
Service Limit: 0.050 mm
No. 3 (New): 0.025 – 0.049 mm
Service Limit: 0.055 mm
No. 4 (New): 0.013 – 0.037 mm
Service Limit: 0.050 mm
No. 5 (New): 0.009 – 0.033 mm
Service Limit: 0.040 mm

6. If the plastigage measures too wide or too narrow, (remove the engine if it is still in the car), remove the crankshaft, and remove the upper half of the bearing. Install a new, complete bearing with the same colour code and recheck the clearance.

CAUTION: 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 next colour listed above or below), and check again.

Note: If the correct clearance cannot be obtained by using the appropriate larger or smaller bearings, replace the crankshaft and repeat the checking procedure.