water proofing a starter motor, advice wtd, what you's done?

[vwjon]

i did some deep wading last year and recently i havnt been using my syncro quite as often as maybe i should, and the starter sh*t itself. i stripped the starter to find the thing full of silt n crap.
do i either silicon seal everything or...
do i drill a couple of holes in the rear case to allow the water and silt etc to drain out?

answers and advice please!

[Aidan]

factory seemed to go heavy on the sealant into the gaps on the solenoid and on case face