Rudder Corrosion - assessment & fix

[twoscompany]

We have a 1988 C-34, hull number 741, that we purchased ~7 months ago.  After spending the summer in the water at a marina slip (So. VA coast / Chesapeake Bay), it is currently on the hard and undergoing inspection / assessment and various repairs as this is the first opportunity we've had - *after the survey @ the time of purchase* - to have a look at exterior things that are below the water line.  Near as we can tell - by memory & by the document itself - the issues were not present at the time of the survey.

BTW :: having not anticipated any rudder work, the boat is positioned such that the rudder tip is less than 6" from ground :/.

There are a few things going on that we wanted to mention in the forum; we are fairly new members, have not yet posted anything but certainly have read our fair share...and primed to continue doing so!

For this post, the focus is the rudder...

At one of our visits during the winter - specifically our third visit, this one in mid-Feb), we noticed a small crack and some rusty-looking fluid seeping/weeping from the rudder (SEE PIC RUDDER_1).  This was not present earlier in the winter.  Much researching later, we decided to open it up a bit - - and it now looks like what you see in pic RUDDER_2.

We have spoken with a few neighbors / experienced sailors at the marina, the yard manager; we've read Tech Notes, spoken with Tech Support @ Catalina Direct, watched videos, even priced a new rudder FWIW :/ .  We just don't know where to go from here.
What do we need to do to thoroughly assess the condition of the rudder/the extent to which its structural integrity has been compromised?  In other words - - what would you do to investigate this issue, soup to nuts?

- -  Do we need to entirely remove the rudder to get the answer - or can this be accomplished by dropping it x number of inches?
- -  What are the steps for removing it considering the current position of the stern/rudder relative to the ground) - if necessary; if not necessary, what are the steps (and likely tricky spots...tips...tricks...) for dropping the needed # of inches to get a good look - - and what are the steps associated with this "good look" at things?
- -  Once done digging/assessing, what is the most appropriate way (thinking "best practices") of repairing the "damage" inflicted whilst investigating?  (i.e., materials and their application / in what sequence / etc.)

I should mention that we are new sailors. I've owned (jalopy) power boats in the past, do all work on our cars & the house (...well, for the most part...) and I love this stuff, but I'm just not familiar, yet, with how everything works.  For example, I've not yet mucked around at all with the emergency tiller / cap; not yet seen underneath the helm; am not yet practiced in the art of glassing...but I'm very willing! I just want to do it *the right way* - not cut corners for the sake of saving a little bit of time/$ etc - which, of course, is exactly why we've come here to present our case!  Thank you to all who contribute & maintain this great resource/community.

[Kyle Ewing]

You can see the quadrant in pics at this post:  https://c34.org/bbs/index.php?topic=8422.0.  Mechanically the rudder isn't difficult to lower, at least on my 1990, just awkward to get to.  Put blocks of wood under the rudder--you can lift it slightly to take pressure off--then remove the cables, quadrant and tiller cap and lower.  There are fewer than a dozen bolts total.  The tricky part might be getting the cap off if there's corrosion.  It's also heavier than it looks. 

If you repair it you may not need to lower it.  If you completely remove or replace it, it looks like you're on gravel so you could maybe dig a (deep) hole to drop it into if the yard can't lift the boat for you.

I had similar weeping the first year or two I owned Donnybrook.  I tried "fixing" by drilling holes to dry it out and sealing around the rudder shaft, but eventually replaced with a new rudder from Catalina.  I was able to do it myself and it's been fine for almost 20 years.  There's a lot written here about fixing vs. replacing.  Someone else will comment on risks of repairing.

If you lower or remove, it's a great time to replace your prop shaft cutlass bearing.

[LogoFreak]

I personally think that you've given yourself more work than needed by grinding the spot on your rudder. I don't think the rudder was going to fail on you as it is, if you want you can upgrade to the elliptical newer style, otherwise just dry it out and glass it back up.

No need to drop it, as a new sailor and someone who hasn't done a lot of boat work I'd say don't open that can of worms. The chances of breaking something during disassembly are pretty high as most likely everything is corroded. Save yourself the headache and enjoy the boat for a season or two before tackling larger projects like this one (trust me it will become a larger project lol)

[twoscompany]

Thank you Kyle & logofreak -

Good suggestion re: cutlass. Similarly (sort of), should we consider doing anything with the packing gland / stuffing box .. anything at the top of the rudder @ the nylon washer .. to assess but also in an effort to 'keep up' from a maintenance perspective - but also to reduce the risk of continued water intrusion?  How far would the rudder need to be dropped to get a look the top of the rudder?

Thank you for the great pix too - very helpful.

Cheers,
Greg

[Ron Hill]

Steve : What you've ground down to is the stainless column.  On the early boats (MK 1) Catalina welded a steel (NOT stainless) grid on to the column so there was something beside the round column to have the fiberglass attach to.  That steel grid is what is rusting.  The water tends to get into the rudder next to the top where the column enters the rudder layup.  Over the years that seal around that entry slightly opens and water gets into layup around that grid.  In the winter that water freezes and that's where your crack and rust came from.

You'll probably have to cut the aluminum cap off because of dissimilar metal corrosion between the Al cap and the SS column.  That will allow you to slightly drop the rudder.  After the rudder is dried out you can re-glass where you ground it down.  Then take a can opener (punch type) and cut a 3/8" deep V groove around the column entry into the layup.  Clean it with acetone and fill with 3M5200 and slide the nylon bushing down on to the 5200.  When all is cured dry then lift the rudder back in place and replace the cap and SS nut & bolt. 

A few thoughts

[KWKloeber]

Then take a can opener (punch type) and cut a 3/8" V groove around the column entry into the layup.  Clean it with acetone and fill with 3M5200 and slide the nylon bushing down on to the 5200. 

Some also seal inside the rudder stock using a foam circle to form a dam a bit below the top, pouring in epoxy to make a plug, or by pouring in epoxy to form a plug in the bottom of the stock.  Belt/suspenders.

[Ron Hill]

Steve : I've written two articles on that "sealing the rudder" topic in the Mainsheet tech notes.  One on draining the inside of the SS rudder column and pouring in some thin epoxy to seal the bottom inside; another on dropping the rudder 4-6 inches and gouging out around the SS column and reseal with 5200. 

Then the inside of the rudder is protected from the two incursion points.

A few thoughts

[twoscompany]

Where are people getting their new rudders these days? 

[AndyBC]

From here: https://www.catalinadirect.com/shop-by-boat/catalina-34/hull-deck/stern/rudders/

I purchased my boat less than 2 months ago.  At the time of the survey, no issues reported with the rudder.  Last week when my boat was hauled out for bottom paint and other work, we noticed that rudder is weeping rust - similar to yours.  The rudder is still solid, and I'm told the rusting is a slow-moving problem.  I'm planning to replace in the next 1-2 haulouts.

Where are people getting their new rudders these days? 

[Ron Hill]

Guys : If you seal the entry where the SS column entries the layup, drain the water out of the inside of the column, and drill holes to let the water out of the layup - you have cut off any new water from entering and drained most all of the water that was there.  To prorogate rust you need water and oxygen!! 

A thought