Toyo Kogyo 4-Speed

INSPECTION
Inspect the transmission case and housing for cracks, worn or damaged bores, damaged threads, or any other damage that could affect the operation of the transmission. Inspect the machined mating surfaces for burrs, nicks or damage.

Inspect the front face of the case for small nicks or burrs that could cause misalignment of the transmission with the flywheel housing. Remove all small nicks or burrs with a fine stone. Inspect the bell housing for cracks. Make sure the machined mating surfaces are free from burrs, nicks or other damage.

Check the condition of the shift covers, forks, shift rails and shafts. Inspect the ball bearings for cracks or deformations and replace any roller bearings that are broken, worn or rough.

Check mainshaft and countershaft thrust play by measuring bearing bore depths in transmission case using a suitable depth micrometer. Measure mainshaft rear bearing and countershaft front bearing heights and compare these measurements with bearing bore depths. The difference between these measurements indicates the thickness of the required shim to be used during assembly. Both mainshaft and countershaft thrust play should be 0.0000-0.0039 inch. Adjusting shims are available in 0.0039 and 0.0118 inch sizes.

Check main driveshaft bearing clearance by measuring bearing bore depth in clutch adapter using a suitable depth micrometer positioned on second step of plate. The difference between this measurement and the measured height of the bearing indicates bearing clearance which must be 0.0000-0.0039 inch. Select a shim for use during reassembly which will bring clearance within specifications.