Thanks Gunni. The brace is in fact the rope cutter - not obvious from the photo. I think you may be right about a crack or desperation of the shaft tube. Alfa and Mechon above mentioned something similar, but I'm not sure if mine is the old or new type of shaft tube
REALLY annoying leak!
- Thread starter Nickeps
- Start date
is your tube fiberglass or s/s Alfa had s/s tube and just used 3m 5200 to seal around the tube . Mine is a fiberglass tube ,I ground the crack back as he did ,you can see it in his picture. He then sealed it with a flexible caulk, I didn't I mixed west epoxy with 404 filler like peanut butter and filled it ,then glassed over making it strong and no movement ,like Beneteau did at factory but with stronger epoxy keeping no movement or flexing of the cutlass bearing.
Hi Nickeps,
Bracket on stern tube is a custom made rope cutter. And from the photos it looks that stern tube is SST. All you need to do is to remove old caulking from the stern tube/skeg interface, allow water to drip and if possible dry interface by directing warm stream of air from a portable electric heater. After that, clean interface surface with Acetone and apply good quality marine caulking pushing it well into the crevice. I had more success using polysulfide caulking compound which cures in the presence of water (I did not used 3M 5200 adhesive). Do not remember brand name, but will look for this. I sealed my stern tube this way in 2015 and so far no trace of leak inside.
All this if you have SST stern tube and would like to restore to original Beneteau spec. If you consider using epoxi resin and glass with SST tube, suggest contact manufacturer. I'm also interested if this is a better method. Good luck.
Bracket on stern tube is a custom made rope cutter. And from the photos it looks that stern tube is SST. All you need to do is to remove old caulking from the stern tube/skeg interface, allow water to drip and if possible dry interface by directing warm stream of air from a portable electric heater. After that, clean interface surface with Acetone and apply good quality marine caulking pushing it well into the crevice. I had more success using polysulfide caulking compound which cures in the presence of water (I did not used 3M 5200 adhesive). Do not remember brand name, but will look for this. I sealed my stern tube this way in 2015 and so far no trace of leak inside.
All this if you have SST stern tube and would like to restore to original Beneteau spec. If you consider using epoxi resin and glass with SST tube, suggest contact manufacturer. I'm also interested if this is a better method. Good luck.
Thanks Alfa. I'm hoping it's as simple as re-caulking as you say. Still unsure of SS/ GRP tube - I seem to have both! Clearly SS on outside, but GRP presumably encasing that near seal inside, see photos. Close inspection outside suggest SS is inside some kind of sleeve, but different diameter to that inside! Confused! And FYI, if I add water to bilge, it does come out where tube meets hull. Must be a crack or something in bilge?
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As in my B31, you have SST stern tube outside the skeg and GRP shaft tube inside the boat with Volvo-Penta drip less shaft seal. Outside diameters of both may not be the same but they are connected together inside the skeg. My B31 has 25mm shaft and SST stern tube has 50mm OD. I did not measure OD of GRP tube inside, but for 25mm shaft, Volvo-Penta shaft seal require 42mm OD tube end. On your picture it looks that another GRP tube is connecting (inside the skeg) SST stern tube with GRP shaft tube inside the boat. On my boat this is not evident (see enclosed photos), but most likely it is similar design. I would remove some material (with dremmel tool or pointy chisel) from the GRP close to SST tube to create crevice for better flexible seal.
I'm not familiar with your boat and can not comment..."And FYI, if I add water to bilge, it does come out where tube meets hull".
Hi Alfa
That's very useful, thank you, and explains the use of the fibreglass. My SS shaft is 30mm so everything a bit bigger I guess in a 42 footer. I will grind out a bit further as you suggest - need to get the best flexible seal I can. Plan for next year is to cruise the Balaerics then Corsica and leave boat in Sardinia in the water for the winter, so need security that it won't sink in my absence!
That's very useful, thank you, and explains the use of the fibreglass. My SS shaft is 30mm so everything a bit bigger I guess in a 42 footer. I will grind out a bit further as you suggest - need to get the best flexible seal I can. Plan for next year is to cruise the Balaerics then Corsica and leave boat in Sardinia in the water for the winter, so need security that it won't sink in my absence!
Nickeps, in your original post you estimated leak of 4l/day. This is relatively large water leak for broken seal around the stern tube. Did you removed flooring from the aft cabin and checked cracks in resin filled skeg? I have one crack in the resin and water ingress on my boat was not more than 1-2 spoons/day. Sealing should be done from outside not inside, but if you have many cracks, maybe you should also consider grinding/drying this area and filling with epoxy? Just to sleep better if your boat is unattended in the winter.
Your plan is to cruise in Corsica next year, great! I'm going end of May to Corsica to hike GR20 trail traversing the Island from N to S. This 180km mountain trail is considered one of the toughest and most beautiful in Europe.
Your plan is to cruise in Corsica next year, great! I'm going end of May to Corsica to hike GR20 trail traversing the Island from N to S. This 180km mountain trail is considered one of the toughest and most beautiful in Europe.
Hi Alfa
Unfortunately I can't get anywhere near the bilge above the skeg as it is hidden under the inner skin.
Your hike sounds great - maybe a little extreme for me! We do a lot of hiking over the stunning mountains and desert here in Spain, where we spend the winter (Facebook or Google "Mojacar Walking Group") and live in Wales on the amazing Pembrokeshire Coast Path, apparently voted in the top 5 long trails in the world.
Unfortunately I can't get anywhere near the bilge above the skeg as it is hidden under the inner skin.
Your hike sounds great - maybe a little extreme for me! We do a lot of hiking over the stunning mountains and desert here in Spain, where we spend the winter (Facebook or Google "Mojacar Walking Group") and live in Wales on the amazing Pembrokeshire Coast Path, apparently voted in the top 5 long trails in the world.