Rudder Bearing Replacement
The rudder had worn bearings and needed replacing as the rudder was in contact with the skeg behind it on one side.
To lower the rudder on W33/Discus you do need to dig a hole. In my case hole was 30cmdeep with boat on blocks of 20cm
Support rudder with ropes, remove quadrant and tap out rudder support bolt. Wiggle rudder from side to side and gently lower into hole.
I had to remove the rudder tube because I needed to rebed it to stop minor seepage
Below this is what the rudder tube looks like. It is in two parts- the top section screws onto the tube. The lower flange is integral.
Under the quadrant four bolts hold a square cover plate in place. Remove bolts, remove cover plate. Then unscrew the main square top plate fitting. Shaft seal sits in recess in top of main square top plate.
Outside there are five bolts to remove. The lower bearing must be prized out before the two bolts closest to the hull can be removed.
New bearings and shaft seal needed.
From the left: Tool to unscrew square top plate, Old shaft seal (compression spring completely gone), new shaft seal, new lower bearing, old lower bearing (note two notches for bolt heads)
Top bearing in tube was hardly worn but I decided to replace it anyway
Top bearing can be removed easily by tapping it out the top of the tube using a plywood pad
This is the surface that has to be sealed. There are 5 M8 bolts (replace these with A4 stainless steel bolts) and the main tube shaft to seal. Note bolt holes countersunk slightly to assist mastic seal.
After much discussion decided to use arbomast bv a butyl rubber based mastic.
Finally realign bolts and rudder tube. Arawa used self amalgamating tape to seal holes. Here rudder is inside tube as it is fitted I plan to fit tube first.
Rudder tube reinstalled - hope it is at the right level!
Rudder ready to lift
Don't forget to antifoul behind rudder before replacing it.
This is the collar that fits on the rudder tube. Note the holes are not symetrical