plastic washer around rudder post

[Ric]

I was cleaning under my boat yesterday, in the space between the top of the rudder and the hull (my boat is a fin-keeler with very high aspect ratio unskegged rudder).

Around the rudder post I found a plastic washer that appeared to have come loose. There was too much crud for me to easily stuff it back and I was running out of air so gave up for now.

Anybody know what this washer is for? I don't suppose it is crucial, but then it wouldn't be there if it did nothing at all.

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[extravert]

It is probably a shim washer put in place when the rudder is assembled. When assembling you put in sufficient washer thickness to get the smallest clearance possible without touching between the top of the rudder foil and the hull bottom above. A gap between the rudder foil and hull is bad if you are interested in milli-knots of performance. My previous X99 had something similar.

If your washer has come out or is in danger of coming out you may find later scrape marks on the bottom of the hull where the rudder foil top has rubbed.

Eventually these washers wear out, like it sounds yours has, and should be replaced. You should only use material suitable for immersion, not all plastic is.

<hr width=100% size=1>One day, I want to be a real sailor. In the mean time I'll just keep trying.