23. Balance Shaft Cleaning and Inspection

Balance Shaft Cleaning and Inspection

Repair Procedure




1. Remove the No. 1 taper head screw plug.
2. Inspect balance shaft thrust clearance.
3. Inspect balance shaft oil clearance.




4. Remove the balance shafts (1, 2).
5. Install the balance shafts.




6. Using a dial indicator (1), measure the thrust clearance while moving the balance shaft back and forth.

0.05 to 0.09 mm (0.0020 to 0.0035 in)

0.09 mm (0.0035 in)

7. If the thrust clearance is greater than the maximum, replace the balance shaft housing and bearings. If necessary, replace the balance shaft.
8. Clean each bearing and journal.
9. Check each bearing and journal for pitting and scratches. If a bearing or journal is damaged, replace the bearings. If necessary, replace the balance shaft.
10. Place the balance shafts onto the crankcase.




11. Lay a strip of Plastigage (1) across each journal.

Note: Do not turn the balance shafts.

12. Install the balance shaft housing.
13. Remove the balance shafts.





Note: Remove the Plastigage completely after the measurement.

14. Measure the Plastigage (1) at its widest point.

0.022 to 0.049 mm (0.0009 to 0.0019 in)

0.049 mm (0.0019 in)

15. If the oil clearance is greater than the maximum, replace the bearing. If necessary, replace the balance shaft.
16. If replacing a bearing, select a new one with the same number.




17. Inspect the balance shaft housing bolts.
18. Using vernier calipers, measure the length of the bolts from the seat to the end.

58.3 to 59.7 mm (2.295 to 2.350 in)

60.3 mm (2.374 in)

19. If the bolt length is greater than the maximum, replace the balance shaft housing bolt.