Water in The Rudder

[mhouse]

You can tell its that time of year by the posts. Here we go.
Having removed the rudder to replace the bearings I can hear water sploshing about so it cant be completly full and I cant see any traces weeping out. Is this anything to worry about or do I just drill a hole , let the water out and then fill it in again ?

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[Jcorstorphine]

If you lived further North there would be the danger of ice foring inside the rudder during Winter and casuing an expansion problem. Perhaps you should look at using a moisture meter to try and locate the exact area where the water is lodged.

You could always drill a few holes and let the water run out and then consider using a can of expading foam to fill the voids. This type of foam actually needs water to assist curing so should fully cure inside the rudder.

You would be advised to investigate the construction of the rudder as you may have some decay going on insde with the posibility of some weakenss in the construction. Best to have a word with local GRP expert. or soemone who knows the internal make up of your rudder.

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[bruce]

it could be serious, if bad rust inside rudder could be ready to fail. you will have to find leak first, drain and repair. inside needs to be inspected.

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[Mooney]

I`ve recently suffered an Insurance Survey showing a high water content in the
rudder.Surveyor said it was very common and didn`t even note it on the report.
I`ve drilled a number of holes and the water dribbled out.It`s stopped now so
I will fill the holes before launch.The water is thought to enter at the point where
the rudder post goes in at the top of the rudder so I intend to put underwater
flexible filler round the join and it may improve.
...Hope this doesn`t cause unfavourable comments from the experts.

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[Robin]

It isn't unusual, mostly it gets in via the shaft as it is difficult to seal where this enters the blade. try drilling a couple of holes at the bottom, hopefully gravity will assist and it will get out, then dry & fill the holes before launching. Most blades will have foam filling around S/S webs attached to the shaft, it is possible that this has been damaged by the water - if you cannot get the water out then you may have to try an exploratory hole or two in the sides at different levels. If there is any hint of 'gunge' coming out it could be disolved foam, in which case it may be necessary to cut out a bigger section, dry the cavity then refoam it and then relay glass mat over the opening, probably you might feel happier with a specialist grp repair man doing this. It sounds a lot worse than it is, I have had this on 3 different boats, 2 were easily cured with bottom drain holes and the 3rd required cutting open and refoaming, cost about £150 for an excellent job done by a grp specialist.

<hr width=100% size=1><font size=1>Sermons from my pulpit are with tongue firmly in cheek and come with no warranty!</font size=1>

 

[claymore]

I had this on a Corribee years ago and the shaft could turn inside the rudder. Once I'd split the blade we could re-engineer the bolt through the shaft but the concerning part was that the blade had several cavities in it where there was no foam and each of them showed evidence of having held water in them.
If you can split the rudder it might be worth doing so to have a proper look inside - other than that, drill it drain it then inject epoxy once its all dried out

<hr width=100% size=1><font color=purple>regards
Claymore<font color=purple>
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[pandroid]

The other posts say it all, however a cautionary tale.

My previous boat (a Contessa) had a crack in the rudder and water seeping from it, which was stained red. We patched it up and it was fine for a few years until I decided the red stuff might be rust and started to worry about it, so I took the rudder back to the original builder. (I had to dig a hole in the marina to get the rudder out, but thats another story...)

They cracked open the rudder, only to find that the red stuff was the foam dissolving and all the stainless work was OK, but by that time they'd destroyed the rudder shell, so they had to rebuild one from the plans.

Well, it turns out the plans were nothing like my boat, the shape around where the rudder met the boat was completely different. It took three goes to get the right profile, and lots of to-ing and fro-ing (you try driving 200 miles with a yacht rudder on the roof!)

On the upside, my boat ended up as the only one in her class where the rudder was built to the plan - and she sailed better for it!

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[Avocet]

Avocet's rudder is usually full of water at the end of each season. Last winter, I drilled a hole in the bottom and let it all drain out properly. I kept the rudder indoors all winter (Mrs. Avocet loves it really!) and then put an air line from a compressor on to the hole. You have to be very careful doing this - just the tiniest puff of air or you might burst the rudder! Anyway, with a wet sponge on it, I found various leaks. I filled some of them but as has been said, some of the water was just seeping past the grp / stainless stock interface. I'm not sure I'll ever seal that joint effectively so I'll carry on draining it each winter I think. I'm lucky in that being a long-keeler, the stock goes into the rudder at the top and out at the bottom. If all the stainless plates inside sheared off due to corrosion, I'd loose steering but not the rudder. I have a couple of pad eyes, one on each side of the trailing edge so that if this does happen I can attach a lanyard to each for temporary steering. Splitting the rudder and investigation of the foam inside is fairly low on my list of priorities at present.

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[oldsaltoz]

G'day Mhouse,

If your leak is at the rudder shaft to rudder interface you will be pleased to know the cure is not that difficult. We have done a number of them over the years and no failures to date.

Grind the glass away at the top of the rudder for at least an inch (50 mm) make sure the shaft is clean at the lower end, now slip on two '0' rings about 5 mm apart, apply a small dab of Vaseline to prevent the resin getting under them and re-glass using epoxy resin and cloth designed for epoxy (Not chopped strand mat) when cured, sand to shape and give it at least 4 coats of epoxy resin to seal it.

Water in the rudder will add weight to the stern, not good, drill holes, lots of them to drain the water and let some air flow to dry out fully. Do Not use expanding foam below the waterline for any reason, it will fail, it has no strength and very poor bonding qualities.
Use only closed cell balloons and epoxy resin, start at the bottom hole and inject the mix with a plastic syringe available from your chemist shop. keep injecting till you see the mix at the next hole above the first, stick some tape over the first hole or plug it with a screw. When filled allow 24 hours to cure, drill / countersink the holes and grind an area about and inch round the holes, fill and fair, coat with 4 coats of epoxy resin, lightly sand and paint.

There that was not too difficult was it.

Avagoodweekend.



<hr width=100% size=1> Old Salt Oz /forums/images/icons/cool.gif Growing old is unavoidable. However, growing up is still optional.

 

[ChrisE]

Well I, for once, will go down the doom and gloom root here. As others have said, itis not unusual to find water in a rudder.

My understanding of rudder construction is that the rudder is formed of two half moulds with a stock in the middle. Stock has tangs on it that are bonded between the two halves and the void is filled with stuff. Stuff absorbs water eventually causing weakness of bond between stock and rudder halves.

Mine did this 10 years ago and we had a new wooden, coated with fibre glass rudder made. I guess how doomy you want to be about this depends upon how confident you are that the insides of the rudder are well bonded together.

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[fireball]

<blockquote><font size=1>Quote from previous post:</font><hr>

Water in the rudder will add weight to the stern, not good,

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Erm ... only when out of the water ... otherwise it weighs exactly the same and less than epoxy filler of the same volume ... still not good though...

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[mhouse]

Thanks for the advise.
The hole will be drilled tonight . It will be interesting to see what colour the water will be!. I expect it must be getting in at the join to the stock but it must be a minute amount since this is the first time its been off for at least 3 seasons. I supose it serves me right for wanting to replace the bearings, otherwise I would not have known.

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[oldsaltoz]

Quote from previous post:
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only when out of the water ... otherwise it weighs exactly the same and less than epoxy filler of the same volume ... still not good though...



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Erm ... think about this a little more Afrogley, if the rudder has no water inside it will have more buoyancy that one filled with water, ie lighter at the stern.

Avagoodweekend.......




<hr width=100% size=1> Old Salt Oz /forums/images/icons/cool.gif Growing old is unavoidable. However, growing up is still optional.

 

[heerenleed]

We have had this on our former boat, a Nicholson 35. We drilled the holes, and also successfully sealed the stock, simply using Sikaflex. Worked well.

cheers

<hr width=100% size=1>Peter a/b SV Heerenleed, Steenbergen, Netherlands
<A target="_blank" HREF=http://www.heerenleed.tk>http://www.heerenleed.tk</A>

 

[cliff]

" for at least an inch (50 mm)"

Duh...... Always thought an inch was 25.4mm approximately not 50 mm

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[Avocet]

It's not just that. Oldsalt is right. Even though the water inside the rudder weighs the same as the water outside the rudder, when the boat is in a seaway, you increase the weight of the part that is moving furthest and fastest. This increases the boat's "polar moment of inertia". This is an effect most people want to minimise. Its the same as having the anchor chain a long way forward. The analogy would be to consider whether you'd prefer to have a 5 gallon drum of water strapped to the forefoot just under the waterline or whether you'd prefer to have it somewhere close to the middle of the boat. A rudder full of water can be an irritating receiprocating mass right at one end of the boat.

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[fireball]

The weight is insignificant compaired to the rest of the boat and location of kit! However, the point I was trying to make (and failed) is that water in the rudder is not heavier than what should be there (some sort of filler I guess). Not that it really matters, water in the rudder is a bad thing in the long term.

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[oldsaltoz]

From your posting:

<<<water in the rudder is not heavier than what should be there>>>

Water IS a lot heavier than what should be there, try pushing an empty container underwater, then fill it with water and try again.

Water in the rudder will reduce the buoyancy of the rubber and increase the load on the support bush causing it to wear, and make the steering heavier.

As well as the risk of internal structural damage due to moisture, this includes the steelwork and the fibreglass, fillers and bonding of all components.

Avagoodweekend.

<hr width=100% size=1> Old Salt Oz /forums/images/icons/cool.gif Growing old is unavoidable. However, growing up is still optional.

 

[Avocet]

That was my experience - I've never been able to feel the difference between a full and an empty rudder and I got about 4 gallons out of mine last time I emptied it! On the other hand, 4 gallons weighs about as much as my anchor and people say it's worth taking them off the stemhead in a blow to reduce the boats polar moment of inertia so maybe there is something in it!

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[fireball]

So the rudder should normally be full of air?!
I thought the keel and rudder were usually solid (with the odd air pocket) ...

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