Broken Upper Rudder Gudgeon

Took my '84 out sailing yesterday and noticed this when I went to setup the boat. Pretty sure the stress was from trailering, not sailing. Since I've owned this boat it's been trailered probably 50x the mileage that I've sailed it. Is this a common failure? Perhaps this is why some people don't tow with the rudder assembly attached?

This is the older of the old gudgeon designs. My '87 has a revised gudgeon that seems to be of improved design. Can I replace this part with the new design... by that I mean will it mechanically align in the same spot?

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Bradley M. Davis - Hobie High Life YouTube Videos
2012 H16 (with 2018 Cayman Main) #115139

Yes and yes.

? To the best of my knowledge, there are only three gudgeon designs - the original ones were nothing more than a strap of metal; the one you have (welded, with a sleeve); and the 1-piece, die cast aluminum ones.

You can replace this with either the 2-piece (like you have) with no re-drilling necessary or go to the 1-piece which will require some filling / drilling / tapping.

I've come across 3 generations of 2-piece gudgeons, with a few revisions or maybe knock-off designs of the 3rd..



The 3rd gens appear to be a far superior design for bending moment load bearing. I'm going with a replacement like the 3rd gen on the far right (those are lowers, and I broke an upper)

You're right - I forgot about the 3rd gen press-formed ones (despite the fact that they're on my 17 - d'oh!). The only downside to them is there's not as much bearing surface - you'll find your pins will wear more quickly and the lowers will wear on the castings unless you have bushings.

Thanks for the tips! As always MBOUNDS delivers. Do you see any issue with mixing a 3rd gen upper with 2nd gen lower? I do have the rudder tight bushings installed in my lower casting and I use SS pins. Just trying to keep it simple and not replace any more parts than necessary.

No issues at all - you get the best of both kinds and with stainless pins, you won't have any pin wearing issues.

I have been trailering with my rudders on for years and have never experienced a failure. From the picture it looks like this may have been happening for a while. Looks like some corrosion in the failed area. A missed aligned gudgeon would induce a constant stress into the system and the weakest member would crack and eventually fail. Have to do some micrographic pictures of the crack surface to really determine the failure mode. Careful alignment of the replacement will probably take care of the problem. I do not think it is a common failure and at least has not been for me.