Sealing a leak at the foam rudder and rudder post

[kito]

Well yet another step backwards on my H30 project boat. I noticed some large blisters on the right side of my rudder that is facing the afternoon sun. I just found out these Foss foam rudders need to be painted a light color or kept out of the sun when on the hard. Well, I didn't know that and painted my entire bottom and rudder black. It's been on the hard for nearly 3 years and was painted a light gray. It didn't develop this delamination until after the black paint Anyway, I drilled some holes and out came about a cup of clear water. I know that the water is most likely dripping from my cockpit drain which is right above the rudder and is running down the top and collecting at the post. I had the rudder centered which made it worst. I am looking for help on how to seal this rudder/post leak.

 

[Gunni]

You won't seal it. Dissimilar materials, and a flexing rudder. The rudder post will pull away from the seal. Need to to drill and drain when on the hard. Keep the holes open until you are ready to splash. Put a couple more up top. A shop vac will help draw it out the bottom. Are they really laminate blisters, or are they frost heave? Open up the blisters and let them dry over the winter. Then you are epoxy prime sealing and fairing. If you have frost heave separation of the skin and core, you will need to cut it away and adhere new glass skin.

 

[centerline]

sometimes the foam filled rudders arent designed to be sealed, and sometimes, even when the manufacture attempted to seal it, it wont remain sealed.... what is the downside to drilling a hole in the bottom of it and letting the water drain thru it like a lot of others?
if the web structure inside the rudder is beginning to fail (break loose from the shaft), it absoultely cant be sealed...

 

[dlochner]

Sealing the rudder post is fairly straight forward.

Drop the rudder and excavate a small trench around the post. Inspect for crevice corrosion. Start filling the void with liquid Lifecaulk (polysulfide caulk). Put some in, let it soak in and begin to set up, add more. When you get near the top seal with the standard Lifecaulk.

Lifecaulk works because it is very elastic and has good adhesion properties. The liquid life caulk will penetrate below the fiberglass rudder shell and help to seal it.

 

[DannyS]

If you decide that repairing the delamination is what you need to do, here's a post on how I did mine. http://forums.sailboatowners.com/index.php?threads/rudder-delamination-followup.117497/#post-708176

 

[kito]

Thanks for the link DannyS. That is exactly what I am going to do....only with the rudder still installed. My H30's rudder is skeg mounted. I would have to remove the skeg plus dig a hole to drop the rudder out. Depending on the depth I need to grind out, I was just going to use kitty hair for the fix and fair it. Deeper ones may require to layer some fiberglass mat. So people with foam rudders need to haul out every year to drain their rudders?

 

[Gunni]

IF you haul the boat, you need to drain the rudder to prevent freeze damage. Leave it in the water you just have a soggy rudder. Rudders are a wear item, they wear out.

 

[Scott T-Bird]

Rudders are a wear item, they wear out.

That's the part that has me worried! I've asked two different yards to drop my rudder during haul-out (on separate occasions) so that I could make a closer inspection of the entire shaft and assembly at my leisure over the winter in a better environment than a boat yard. I have no particular reason to worry. Both times I was talked out of it because of the labor expense to detach the radial drive wheel. Bolts are frozen & access is very difficult. I've even conceded that if it was necessary to break the wheel, I would buy a new one. The response I get is "if it ain't broke then don't try to fix it" and it's too hard to argue.
Then, during the season, I often find myself wondering how will I know BEFORE my rudder falls apart?

 

[Gunni]

How will you know? You will see blistering, delamination, rust seepage, cracks in the skin. I would suspect any rudder older than 20 years that spends significant time in the water and is sailed hard. My rudder has a composite post that bends. Under stress it bends off several inches at the tip!

 

[dlochner]

Here's a link to the first in a series of videos on rebuilding a foam core rudder.

Once the bolts are freed up, dropping a rudder is not that difficult. Copious amounts of PB Blaster and lots of heat can convince the bolts to give up their death grip on the quadrant. The issue is aluminum quadrant, SS shaft, and SS bolts. If you do remove your rudder be sure to use lots of Tef-Gel on the bolts when it goes back together. Also if you have a gas engine, the heating part can get tricky or deadly.

 

[Scott T-Bird]

Once the bolts are freed up, dropping a rudder is not that difficult. Copious amounts of PB Blaster and lots of heat can convince the bolts to give up their death grip on the quadrant. The issue is aluminum quadrant, SS shaft, and SS bolts. If you do remove your rudder be sure to use lots of Tef-Gel on the bolts when it goes back together. Also if you have a gas engine, the heating part can get tricky or deadly.

The problem is that nobody wants to leave the boat on the travel lift for the amount of time it takes to free the bolts. Once the boat is on stands, the rudder can't be removed ... the tip is a mere inches off the ground. I suppose the key is to free up the bolts before getting to the travel lift ... ah, there's always something that I'm not particularly anxious to do!

Gunni, my rudder is 32 years old and presumably in the water every season for its life (except for maybe the season before we purchased her). I see none of those signs. The only thing I've ever noticed is a tiny amount of clear water seeps out of the leading edge seam and only for a day or two after haul-out. I can see that the seam is open slightly at the top, at the shaft, but nothing dramatic, just a hairline opening. The rudder has been scuffed at the tip and I notice clear water leaking from the scuff for an equally short period. It has always appeared to be dry before we have any freezing weather. I've never drilled to drain the rudder, nor do I particularly want to. Even though it is painted the same red as the bottom paint, I've never noticed any heat that would be considered alarming, even on a sunny day. I can't see anything unusual from year to year and we've had it now for 12, but I don't know what I don't know about this rudder and that is what bothers me.

 

[dlochner]

Scott,

Once the boat is on the stands, work on removing the bolts. Drop the rudder in the spring or replace the bolts with new bolts coated with anti-seize (Tef-Gel) and drop the rudder next fall.

If you are getting water out of the rudder, then water is getting in. You don't want to seal that into the rudder until it is dry or when it freezes the rudder will crack open again.

 

[Scott T-Bird]

Scott,

Once the boat is on the stands, work on removing the bolts. Drop the rudder in the spring or replace the bolts with new bolts coated with anti-seize (Tef-Gel) and drop the rudder next fall.

Thanks! That's actually a great idea, coming from somebody who has a good deal more foresight than I typically exhibit!

 

[Gunni]

No big deal to drill a few 1/4" holes in the tip and let it drain over the winter. scuff em up with 80 grit in the spring and fill them with marine-tex

 

[dlochner]

Thanks! That's actually a great idea, coming from somebody who has a good deal more foresight than I typically exhibit!

Thanks, but don't over estimate my foresight. I seem to spend a lot of time undoing the mistakes I've made.

 

[DannyS]

I'm planning to drop my rudder again next weekend. Last spring I noticed some more delamination that I want to stay ahead of so off it comes for the winter. The boat is on the cradle so I'll need to dig a hole under the rudder to get it out. I'll take photos of the disassembly process. It was not that hard last time, access is the only main issue.