Outer Limits 4x4 Board

Just curious to know how people prevent there starter motors from clogging up with mud an water... just recently put a new starter on my rangie an got one day drive out of it and it was cactus!!! full of mud an splatted all the internals into a whole heap of pieces, 80diesel4play can vouch for this!!! just wondering if you guys shield them or ??????
Any ideas would be appreciated!!

I have a nippon denso toyota starter fitted to my rangie ,this has been converted by an auto electrical remanufacturing company here in nz but Im sure someone in oz must be building them ask your local auto sparky.They are a bit more water proof than the old lucas units.
cheers scott