Rudder Osmosis - 2003 Bavaria 38

[simonmoore]

Hi, i have had a pre purchase survey done on a B38 and it shows the rudder blade has three separate areas of blistering.  Has anyone else had a similar experience and idea of cost to repair?

[Murphy]

Hi, when we purchased our Bav 30 last year our pre-purchase survey stated the rudder was showing signs of delamitation.  After some renegotiating with the seller we still went ahead with the purchase.  We had the rudder removed and taken to a workshop to dry out.  After further investigation, they carried out a resin injection on the blade which seemed to do the trick, thankfully there was no requirement to split the blade as i believe that's when it gets pricey. At the same time we also replaced all the rudder bearings as well as a few other little jobs.  The total cost was under £1000 on the South Coast.  Good luck with the purchase

[IslandAlchemy]

Mate of mine is a yacht surveyor and says it's common on Bavarias because the rudder is polyester resin.  Mine has had a couple of doses of blisters and I now just ignore them and paint over them.

[simonmoore]

Thanks everyone  that's a great help.

[Spirit of Mary]

Mate of mine is a yacht surveyor and says it's common on Bavarias because the rudder is polyester resin.  Mine has had a couple of doses of blisters and I now just ignore them and paint over them.

My opinion this is nonsens.
Indeed polyester resin has a higher chance for osmosis. However when well produced this risk is very very small. The hull of all Bavarias is fabricated with polyester resin and osmosis on these hulls is not an issue at all.
Solution for the TS, treat the three separate areas and after repair, paint the whole rudder with > 5 layers of epoxy.
Reg,
Ger

[Salty]

I'm inclined to agree with IslandAlchemy regarding the risk of osmosis, but in regard to the number of coatings of epoxy, and assuming that these are paint coatings, be sure to rigidly follow the manufacturers over coating time schedules. Get it wrong and the extra coats will be a waste of time and money.

[PEA-JAY]

There is no ?cure? to osmosis on a Bavaria rudder.
It just keeps re-occurring irrespective of what you do. 
If you cannot live with it the only solution is to either buy a new one or re-manufacture the old one, meaning use the old blade as a plug to create a mould and rebuild a new rudder from scratch.

[Imagine]

I have a 2002 Bavaria 36 which has this problem.i have touched it up this year but in the winter I am having it stripped and repaired properly at a cost of 1500£ I priced a new one but that is far to expensive..

[Craig]

Others may confirm this or correct me, but I have been led to believe that the rudders are not made by Bavaria but purchased from a Danish company that supplies rudders to many of the larger production boat companies.

The rudder does appear to be the only place you are likely to get Osmosis on a Bavaria.

The rudder takes extreme flexing stresses compared to the hull and this may contribute to the issue. I know of other issues involving the metal in the rudders flexing or cracking as well.

Minor groundings may lead to cracks in the bottom allowing water to enter the foam.

I think Bavaria changed the rudder bearing set-up about 2010. The previous bearings were subject to swelling of the "nylon/plastic" bottom bearing leading to a stiff helm. There is a good YouTube clip by a Portuguese yard showing how to install the new bearings.

Craig
"Shirley Valentine"
Gold Coast
Australia

[landes_h]

Rudders were also produced in Slovenia. The company aproched this Board in order to inform about their clearance sale.
See here in case someone need rudders or other parts:
http://www.bavariayacht.info/forum/index.php/topic,1256.0.html

[Yngmar]

The water gets into the rudders at the top, where the steel rudder post joins the fibreglass. The osmosis then happens from the inside out, rather than the outside in as is the case with hull osmosis (which Bavarias aren't known to suffer from, despite being made from the same polyester resin). To prevent this water ingress, Jefa suggests a flexible Sealant filler around the top where the post goes into the rudder: ftp://ftp.jefa.com/rudder/maintenance/Rudder_blade_anti_fouling_instructions.pdf

This wasn't done by Bavaria and/or their rudder manufacturers for a long time. Once the water is in the rudder, you can drain some of it out (drill holes, drain and fill) and spot-treat the blisters, but as the rudder is PU foam filled it will never completely dry out. There's several threads about rudder issues on these forums worth reading.

[PEA-JAY]

You are 100% spot on. In my case the rudder always comes off the boat when I lift her out. We do so as a matter of fact. It looks like Swiss cheese now as new blisters keeps forming every time and this year I plan to replace it. May I suggest to anyone buying a new rudder to create a water tight seal by milling a canal in the space where the stock enters the blade and do the same in the spacer that sit over the stock at this point. I also placed three s/s grub screws to help keep the spacer tightly in place. I fill the cavity with a Wurth brand compound used by motorcar body repairers to glue on fenders to the car. This compound forms a fantastic bond and forms a flexible watertight joint at this critical point. It worked perfectly time and time again. I find no water in the rudder but it has been  compromised by a sloppy installation when the boat was built in 2005. Raph.