Case 580B CK engine shuttle gasket......

[Hankstains]

Got an old 580b and it runs great, only problem is, it has more leaks than a welsh farm. Worse one is between engine and torque converter. Seems like the problem was there before as it has some gunk stuck round the joint. Was OK but I just changed the water and milk for some nice oil and now it leaks like a sieve.
Question is.....can you split the engine and shuttle just enough to get some silicone in it or do you have to split it completely. Heard some stories of silicon blocking the intake tube for the shuttle so not keen but also not keen on splitting the old girl. If it is a split, I guess the hydraulic fluid has to be drained and the pump removed etc. etc. etc........a bit of a nightmare, any advice, greatly received.......

[Stock]

what oil is leaking? ATF which is red or black engine oil? if you seal up the bell housing the oil will leak into the sealed area and eventually fill until it can find another means of escape............................................ ....