Of course your setup may be (probably is) different.

The shoe at the bottom of my skeg used a cut down piece of a cutlass bearing. The weight was carried by a plastic washer between the shoe and the rudder. There was no drain hole in the bottom of the shoe.

The problems with this setup are:

1) The washer is a poor support and wears away over time.

2) Debris such as barnacles and other scrapings from the bottom builds up over time in the "socket" in the shoe. This grinds away at the cutlass bearing.

I had replaced the cutlass bearing in 1995 - it was chewed down to nothing. At that time I drilled a half inch hole at the bottom of the socket. I did nothing about the washer supporting the rudder weight. The boat was ten years old then.

In 2008 I rebuilt the entire rudder "system". The top and mid bushings were replaced with custom machined plastic and were made longer for better wear. The rudder post tube had to be cut out and re-glassed in because it had been installed at an angle by the builder. It appeared that the bearing inside the tube had been ground out to fit the rudder, rather than fixing the misalignment.

Getting back to the shoe: When I pulled the shoe (13 years and about 80,000 nm later) the cutlass bearing was still pretty good. The hole in the bottom worked - the debris had washed out instead of sitting there grinding it down. The support washer was badly worn. This time I had a bronze spacer machined to fill the gap between the rudder post and the bottom of the socket to support the rudder weight. The spacer has a large hole down the center and grooves cut across the bottom so that (hopefully) any debris will washout. The weight of the rudder is now on a metal to metal (2'solid stainless post to bronze spacer) wearing surface - very low friction. A new washer is in there in place of the old load bearing washer but it's only role now it to try to keep debris out of the socket. And of course I also replaced the cutlass bearing.

How well will this work? Well, ask me in ten years.