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T-90 Rebuild Question

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I'm rebuilding a T-90 using a master rebuild kit.  All the new parts look to be of fine quality and I have been very meticulous during the process but seem to have run into what might be a problem.  I noticed that after I tapped in the reverse gear idler shaft, the gear seems to be frozen and will not turn by hand.  I have not tried to force it yet as I do not want to mar any teeth.  I have been using engine assembly lube & motor oil on the parts during installation so the shaft & inside of the gear were lubricated before installation.  There is a notch cut in the shaft that I'm assuming is for oil to make its way to the area where the gear is to turn on the shaft( not the groove for the lockplate, this runs the length of the shaft).  My question is, should I continue with the build under the thinking that it will break loose once gear oil and engine pressure is applied, or should I remove the shaft/ gear for inspection.  P.S both the gear and the shaft are new from the kit and the gear has a brass looking sleeve on the inside diameter.  Any thoughts or tips would be appreciated.

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I'll jump into this one, having rebuilt B-W transmissions for many years. The reverse idler gear has an internal bushing, not a needle bearing approach. (The gear sees very little use, comparatively, so the use of a bushing is not an issue.) This bushing has the ability to hold oil, and as you note, there is a provision for oil flow to that area.


If you were able to tap the reverse idler shaft into the gear without effort, there is likely a minor burr or very slight out-of-round on the bushing. Had you attempted to spin the gear on the shaft prior to installation, perhaps this would have been evident. At this point, you can either remove the reverse idler shaft and gear to check fit or take the other approach and leave the gear to run-in once installed. Depending on the amount of effort it took to install the idler shaft through this bushing, you may find that simply turning the input gear on the bench, with reverse engaged, will rotate the gear and get it to turn freely.


Should you discover that the bushing has a burr and binds, remove the gear. A drill motor and three-stone brake hone, worked lightly with a light oil, can be used to true the bushing. In any case, once in service, the bushing will "burnish" and operate easily!


Trust this helps...Moses    

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