Bob Labuz wrote:
> Gearbox experts,
>
> I dissasembled the internals on a TR3A gearbox (non OD) for cleaning
> and inspection and to my surprise the bronz bush for 2nd gear is cracked
> at the collar. It almost appears that the bush is 2 parts. The bush wont
> separate into 2 parts, the crack is about 75%. There is no evidence of
> heat scorring, scratches, nicks or anything that could explain why this
> part is cracked. All gears and shafts etc are in perfect shape. This
> gearbox was on a 1959 that I owned way back in 1968 - 71 and the
> transmission shifted like a dream. The 3 was involved in a terrible head
> on collision which caused the transmission case to break right where the
> bell hosing meets with the box proper. There is no other evidence of
> damage from the collision. Could the impact have caused the crack?
>
> Eventhough the part fits fine, I have decided to replace the bush with a
> new one. Would hate to have it self destruct.
>
> Has anyone else ever experienced this with a gearbox rebuild?
>
> Bob Labuz
>
> 1958 TR3A
> 1974 T140V
This crack in the "tophat bushing" is very common. It is usually the first
part in the transmission that fails. It is not caused by some external
impact. What happens is that the flat portion of the bushing or gears wears
enough to put pressure on the flange portion. You need to replace the
bushing and to carefully re-set the clearances per the factory book, which
takes a small amount of shims available from Moss, etc.
--
uncle jack
The Attorney General advises that vintage racing may be hazardous to your
wealth.
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