Countershaft And Reverse Idle Gear Inspection
Reference: COUNTERSHAFT DISASSEMBLY AND ASSEMBLY
- Using micrometer, check diameter of countershaft (1) and needle bush (2) as shown. If measured value is out of specification, replace counter and/or bush.
Countershaft diameter (standard)
COUNTERSHAFT DIAMETER SPECIFICATIONSMeasuring portion Standard "a" 25.002-25.015 mm (0.9843-0.9848 in.) "b" 27.987-28.000 mm (1.1019-1.1023 in.) "c" 27.987-28.000 mm (1.1019-1.1023 in.) "d" 30.959-30.975 mm (1.2189-1.2194 in.) "e" 34.975-34.991 mm (1.3770-1.3775 in.) "f" 25.002-25.015 mm (0.9843-0.9848 in.) "g" 28.000-28.013 mm (1.1023-1.1028 in.) "h" 34.975-34.991 mm (1.3770-1.3776 in.) - Measure width "a" of low speed gear shift fork and groove width "b" of low speed gear synchronizer sleeve and then calculate clearance "c" as follows:
Clearance "c" = "b" - "a"
If clearance exceeds limit, replace fork bush (1) and sleeve.
Clearance "c" between fork and sleeve
Standard: 0.2-0.5 mm (0.008-0.020 in.)
Limit: 1.0 mm (0.039 in.)
- Check clearance "a" between synchronizer ring (2) and gear (1), key slot width "b" in synchronizer ring and each chamfered tooth of gear and synchronizer ring and replace with new one, if necessary. Also, check gear tooth.
Clearance "a" between synchronizer ring and gear (Countershaft) (1st and 2nd)
Standard: 1.0-1.4 mm (0.040-0.055 in.)
Service limit: 0.5 mm (0.020 in.)
Key slot width "b" (1st and 2nd synchronizer ring)
Standard: 10.0-10.2 mm (0.394-0.401 in.)
Limit: 10.45 mm (0.411 in.)
- Using cylinder gauge (1), check inside diameter of countershaft 1st and 2nd gears (2). If measured value exceeds specification, replace countershaft 5th gear.
Countershaft 1st and 2nd gears diameter
Standard: 40.000-40.025 mm (1.5748-1.5757 in.)
- Check oil clearance between reverse idle gear (2) and shaft (1) measuring inside diameter "a" of gear and diameter "b" of shaft and calculate as follows:
Clearance "c" = "b" - "a"
If clearance exceeds limit, replace gear and shaft.
Oil clearance "c" between reverse idle gear and shaft
Standard: 0.016-0.045 mm (0.0006-0.0018 in.)
Limit: 0.13 mm (0.005 in.)
- Check clearance between reverse idle gear (2) and lever (1) of reverse gear shift link. If clearance exceeds limit, replace gear and lever.
Clearance between reverse idle gear and lever
Standard: 0.05 mm-0.25 mm (0.002-0.010 in.)
Limit: 0.5 mm (0.020 in.)