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Sun Odyssey 45 Rudder Loss

Danger from undetected DC stray current corrosion

 

We are Oskar and Lisa, who made the Youtube video below about the total loss of our rudder well offshore in the Pacific in December 2018.

 

 

We have received many comments regarding the rudder loss. First of all, we want to say that the rudder was not lost due to construction failure but through damaged by electrolytic corrosion from stray DC current.

 

On our Jeanneau Sun Odyssey 45, the steering house is made of aluminum. In the steering house there is a Plastimo compass with lighting. The cables to the lighting had been damaged and DC current leaked through the house to the wire, quadrant and finally to the rudder shaft. Since the propeller shaft is negative, a leakage current was created between the rudder shaft and the propeller shaft, which caused corrosion. The propeller shaft has zinc and therefore it was no damage there.

 

About 1.5 years ago we dismounted the rudder and then there was no damage at all. The corrosion has therefore started after that and probably in the recent months. We would say that the construction of the rudder is good and there is no need to worry about the construction for other Jeanneau owners. On the other hand, we really recommend an inspection of the electrical cables in case you have a metal steering housing since that can lead to leakage current.

 

We have now fitted a zinc to our rudder by connecting a cable inside the hull to our bonding system. We have a large zinc on the hull that we have connected to the gearbox so propeller shaft, propeller and now rudder are now protected for corrosion.

 

Right now we are in the Marshall Islands in the Western Pacific. We are in a remote place in the world. When we lost our rudder, Jeanneau handled the situation quickly and made a new rudder for our boat in France. Despite being so far away, Jeanneau managed to arrange shipping and within a month we had a new rudder in place here in Marshall.

 

Jeanneau provided this parts diagram plus advice, so we could order all the correct new bearings etc

 

Jeanneau also supplied this lifting eye, which can screw into the top of the shaft, to assist with lifting it into position.

 

 

Jeanneau has been very professional and we had good service and we are happy that it was possible to manufacture a rudder so quickly. We are really happy to be Jeanneau owners since Jeanneau acted so professionally and quickly.

 

We could not haul out here in Marshall. Therefore, it was only possible to mount the rudder in the water. Since the shaft tube is above the waterline, we could mount the rudder in the water without leaking in water. To begin with, we moved our boat “Hilma” to a calmer anchorage, we needed to have calm water to mount the rudder. To move Hilma, we put the engine in reverse while we towed our dinghy with a long rope from the bow. The one who operated the dinghy controlled the steering of Hilma by reversing the outboard in the opposite direction to the direction of the boat. We towed the rudder with the dinghy afterwards and let rudder hang in a rope under the boat.

 

The rudder has negative buoyancy, but the lower part of the rudder has positive buoyancy and the rudder therefore wants to turn in the water with the shaft downwards. To get the rudder in the right position, we hung about 15 kilos of weight in the bottom and then the rudder turned in the right direction.

During the assembly, we put a hoist between our arch, main halyard and the rudder. Lisa pulled up the rudder through the cockpit while I steered in the rudder through the hull beneath in the water. The assembly itself took no more than two hours in total.

 

As the film shows, it took us four days to get to a sheltered bay. We have had a number of issues regarding emergency steering and our experience is that it is more difficult than it seems to control a boat without a rudder. We tried to steer with a drogue, but it was very difficult to get control of the boat with that method. It certainly is easier in calmer conditions, but with waves it was almost impossible for us. We had the wind towards us large parts of the days at sea and then it was difficult to balance the boat with the sails. A long keel boat would surely have done better. We soon realized that the only way for us to get control of the steering was to make a rudder, and it finally worked. A wind vane with "its own" rudder had surely solved the whole problem, but sadly we do not have one.

 

Unfortunately, it is difficult to practice steering without a rudder since it assumes that one have to remove the rudder before leaving shore. There are a lot of films on YouTube where different methods are shown, but if the boat has a rudder, it will help the steering a lot when use of a drogue for example. Though the rudder helps the boat to stay on course.

 

We have learned a lot from this incident and hopefully others can benefit from our case. Above all, it is important to ensure that the rudder is in good condition and that there is no corrosion on the shaft. It is also a good idea to inspect electrical cables where there is a risk of leakage current. It is not just risk with AC power, but also DC power can create great damage. It is a good idea to ensure that there is zinc connected to the rudder shaft, preferably via the bonding system. We can also suggest using wind vane for ocean sailing, we wish we had one.

 

Now we have repaired everything on board that was damaged during the incident and soon we can sail towards Federated States of Micronesia, Palau, Philippines and beyond.

 

Fair winds

 

Lisa and Oskar - SO45 - Hilma

 

www.youtube.com/hilmasailing

www.sy-hilma.com

 

Editor note: One method to check for potential stray current circuits and electrical conductivity is using equipment such as this Galvatest unit.

 

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