There really is nothing to do to the "non-serviceable" rudder. The bottom "seal" is porous and allows lake water to enter into the rudder shaft chamber lubricating it, the top seal prevents water from entering the boat. If you have this type of rudder system, you may have to replace it with a serviceable one once your warranty is up.
To find out if you have this rudder box, take off your starboard side engine divider in your rear locker, reach down behind the motor and feel the 6" or so rudder housing riser to see or feel if you have 1 or 2 zerk fittings sticking out a little bit (1/2" or so). If your riser is smooth with no zerks, you have a non-serviceable rudder. Here is a link to the malibucrew with pictures of one a member was selling. You can see the 2 zerk fittings on the housing in this photo. If he still has this for sale, someone needs to jump on it as I think it is the same year my replacement housing is and may just fit our boats.
http://www.themalibucrew.com/forums/ind ... r-housing/
