Th350 shaft seal leaking

[Gromit]

Might try some fine emery cloth on the shaft where it meets the seal - any imperfections in the metal will abrade the replacement seal. Obviously still have to replace the current seal but that might have been the issue and if so it will happen again with the new seal. I can't recall what grit I finished mine with but pretty sure at least 400 grit and probably 600 grit; there was quite a burr built up on the shaft - in fact I think one of the manuals says watch for that and don't force the shaft out through the case without deburring it.