I`ve had the same problem with my 1952 IHC L-130, which is powered by a 220 "Silver-Diamond".
After replacing the seal the 2nd time, I followed the advice of a farmer friend of mine.
His theory; since the trucks set in the barns, except during harvest time, and have usually been serviced with "multi-grade oil", the seals tend to dry out and the lower viscosity multi-weights seep through.
I changed to a straight weight 30. The seal hasn`t leaked yet.
Still don`t know whether I might just have had a better "seal installation", or the differance in oil solved the problem?
