M/T Countershaft Inspection

1.

Inspect the gear surface and bearing surface for wear and damage, then measure the mainshaft at points A, B, and C. If any part of the mainshaft is less than the service limit, replace it with a new one. Standard: A (Ball bearing surface):  24.980-24.993 mm (0.9835-0.9840 in.)  B (Needle bearing surface):  37.984-38.000 mm (1.4954-1.4961 in.)  C (Needle bearing surface):  34.000-34.015 mm (1.3386-1.3392 in.)  Service Limit:  A: 24.93 mm (0.981 in.)    B: 37.934 mm (1.493 in.)    C: 33.95 mm (1.337 in.)

2.	Inspect the runout by supporting both ends of the countershaft. Rotate the countershaft two complete revolutions when measuring the runout. If the runout exceeds the service limit, replace the countershaft with a new one. Standard:  0.02 mm (0.001 in.) max.  Service Limit:  0.05 mm (0.002 in.)