Was the bearing oil seal neoprene rubber lip or O.E.M./ORIGINAL A1 (leather lipped)?,
If it's the former there known to cause leaking ,
As the rubber material gets hot it gets hard &sometimes wears the shaft,
At worst causing a groove in the shaft which negates the use of a aluminium sleeve,
(Speedie sleeve made by C/R&NATIONAL oil seals).With leather oil seals you have to&must soak them for 24 hrs in light engine oil to soften up the leather otherwise they'll wear the shaft surface causing wear i.e. groove, a neoprene lip oil seal only needs a smear of grease or oil ,in our over 50yrs expereince with oil seals for vintage cars we' ve found the leather oil seals better suited to both old style metallurgy&lubricants &out last&out perform neoporene rubber oil seals.