1960s Speedo gear seal

[oregonjam]

Should there be a seal on the speedometer driven gear shaft sleeve to the tail housing?

I disassembled and there was no seal there. Should there be one or was thread sealant used?

Thanks,
John

[The Tassie Devil(le)]

No seal, or sealant on the thread.

The speedo driven gear shaft should have a spiral wound groove in the outer circumference to "wind" the excess transmission oil back down the shaft.

This is sufficient for oil retention within the transmission.   Any oil leaking out will mean that the transmission is too full.

Bruce.

[bcroe]

My experience with a TH400, is the plug supporting
the speedo driven gear has an outer O ring to the
case, and an inner seal to the plastic gear, both
replaceable.  The problem is the plastic wears and
may no longer make good contact with the inner seal. 
Bruce Roe