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April 17, 2008 at 8:51 am #6158Anonymous
A small quantity of water is seeping in through the aft keel bolt of my 1999 38 Ocean. This appears to be an historic problem, as there was a quantity of clear sealant around this one bolt (I have only owned the boat since last May), which was apparently stopping water getting into the bilge in the engine bay until recently. It is quite possible I disturbed this sealant while cleaning the bilge.
Do any members have experience of leaking keel bolts? If so, do you have any advice regarding solutions and/or any recommendations of suitable boatyards who might help in the Solent area. Applying sealant to the inside of the boat seems to be ignoring the basic problem of water getting in around the keel bolt in the first place. It has been suggested that a short term solution might be to torque-up the bolt, but I am concerned that this may risk making matters worse.
I should be grateful for any information.
Regards
John GoldingApril 18, 2008 at 9:45 am #7520AnonymousJohn
I have a (year) 2000 38 Ocean and, to date, have had no problems with water in the bilge – in fact it has been the driest boat I’ve owned – so your problem is not typical.
Where is the water exactly and are you sure it is seawater from around the keel bolt? I have had fresh water in the engine compartment from poor sealing around the cockpit drains and also around the instrument binnacle. The water actually collects at the front of the engine over the keel bolts, so the source was not immediately obvious.
If it is the keel bolts that are leaking, is there any evidence of the keel ever having received a hard knock (e.g. hitting a rock or otherwise grounding)? If so, I would suggest you need to get a survey by an expert (but I can’t recommend anyone).
If not, it might be worth trying a temporary ‘repair’ (dropping the keel to effect a permanent repair is not a trivial job). You could remove the offending nut and use epoxy putty (which sets even in the presence of water) under the washer, around the thread (but not too much otherwise you’ll never get the nut off again when the time comes) and then torque the nut up as hard as you reasonably can. I don’t think this will make the problem any worse.
If the boat is out of the water (and the threads dry) then you can substitute silicone sealant for the epoxy putty.
I think any attempt to seal around the keel to fibreglass joint on the outside, without dropping the keel and doing a ‘proper’ job, is unlikely to succeed.
Good luck.
Roger
PS Did you have a full survey carried out before you bought the boat? If so, you might have some claim against the surveyor.
April 22, 2008 at 11:03 am #7524AnonymousRoger,
Thanks for your reply.
The water is definately coming in through the bolt, although it is a very small amount. I also had a fresh water leak, which turned out to come from the Pressure Relief Valve on the calorifier and now seems to be resolved (new PRV).The boat was surveyed before I bought it last May. There was no evidence of any impact and the keel joint appeared sound at the time with no obvious movement. The surveyor failed to comment on the sealant around the bolt, so I guess there may be a claim opportunity if necessary.
I have now spoken to two shipwrights who have suggested more or less as you have regarding a short term fix. When the boat is next out of the water I plan a fuller investigation and probably trying to draw out the offending bolt (stud) to check for corrosion before re-sealing. As you say, dropping the keel is a big job and at present the last resort!
Regards, John
April 27, 2008 at 10:48 am #7526AnonymousHi John,
If i had a leaking keel bolt, i would look to the permenant repair being a job for the next time you lift out, but as a temporary solution try the following. Get a nylon or fibre washer big enough to fit the keel bolt. Wrap the lower threads of the keel bolt with plenty of ptfe tape. Fit the flexible washer, followed by the steel washer and then the nut. Tighten the nut to the correct torque setting and at the same time check the torque on the remaining keel bolts as they should have been checked when the boat had sailed for its first season. It may be necessary to re torque the leaking bolt again during the season as the flexible washer may continue to compress slightly under load, but i doubt it. Its amazing how much load can be taken by flexible washers that are well compressed.
When the boat comes out of the water you need to look at the keel to hull joint. Providing there is no sign of movement and the flexible joint still being in place, i would recommend you withdraw the bolt part way, apply a good waterproof flexible sealant to the withdrawn section and then screw it back so the sealant is taken into the hole for a considerable depth.
Regards,
Alan Burns.
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